A new Web site for Airpot Corp., Norwalk, Conn., provides many useful features, including easy-to-search products and frequently asked questions, reflecting more than 50 years of applicable knowledge. Additionally, 3D CAD files of nonstock products can easily be configured with construction requirements tailored to the application and meeting designers’ needs. The new site also details specifications and information on Accurate Force Pneumatics (AFP) systems and components, which aid designers when creating these systems that combine cleaner regulated air, proportional pressure control, and precise actuation.

For more information about Airpot or its products, call (800) 848-7681, or visit the Web site at www.airpot.com.

Mobile-equipment designers continue to exploit the advantages of hydrostatic drives for off-road vehicles, typically using a single pump to power wheel motors in a parallel circuit. This hydraulic circuit performs like the mechanical differential in a conventional, mechanical drivetrain.

For example: when the hydrostatic-driven vehicle corners, the outer wheel motor must rotate faster because it turns on a longer radius than the inner wheel. To do this, the outer wheel motor must receive greater flow. Otherwise, it is dragged through the corner by the inner wheel — causing skidding. The parallel circuit prevents skidding by directing adequate flow to each wheel while delivering constant power to the traction drive. The same hydraulic differential circuit also accommodates differences in tire diameter due to wear, uneven wheel loading, and differences in ground contour at the point of wheel contact.

However, in driving situations where one wheel loses traction — in mud, snow, or ice, or by bouncing off the ground — the differential circuit would allow full flow to the wheel with the least resistance, resulting in wheel slip. To avoid wheel slip, positive traction at all wheels is required. One way to accomplish this is to route pump flow through a flow divider and then to the wheels. By its nature, the flow divider ensures that each wheel receives equal flow and eliminates slip. But now the drive is subject to skid.

A hydrostatic drive can handle both slip and skid by using our gear-type flow divider with an integral, solenoid-actuated two-way valve incorporated between the output ports. Normally, this valve is in the position to provide the differential circuit that is required by most driving conditions. However, when wheel slip becomes a problem, the operator energizes the valve to divide flow for positive traction. The operator then switches back to differential for normal travel.

An alternative design substitutes an integral needle valve for the two-way valve. The needle valve’s orifice is preset for the type of terrain to be covered. The circuit then provides a compromise, constant-drive condition that is not full-differential nor full-positive traction. There always is enough flow to each branch to assure rotation of both wheels, while still allowing smooth cornering without skidding.

THIS INFORMATION was provided by Matt Christensen], of Concentric Rockford Inc. (formerly John S. Barnes Corp.), Rockford, Ill. For more information, call (815) 387-4617 or visit www.concentricab.com. See this product at IFPE Booth 80908.

Most forklift trucks used in warehouses rely on an operator to keep loads level. Such is not the case with all-terrain forklifts, where uneven and unstable ground are expected. Keeping loads level on aerial work platforms is even more critical because the load usually consists of people.

Level sensors (inclinometers) were developed to provide feedback to a machine control to keep loads level. Today’s closed-loop electrohydraulic systems can provide automatic leveling. To accomplish this, the inclinometer sends an analog-based signal to the machine’s control, which then commands a proportional hydraulic valve to shift one way or the other to keep the load level.

Traditional inclinometers monitor a single axis of orientation — typically roll or pitch. However, the Model LPI inclination sensor from tecsis LP, Worthington, Ohio, monitors orientation in two axes. This sensor can be configured to provide dynamic or static incline or tilt angles between 0 to 360° (single axis) or ±45° (dual axis) with a resolution of 0.01°. Predefined measuring ranges can be selected to suit the application, and switch outputs provide control based on limit angles.

The Model LPI’s IP67-rated aluminum housing makes it well suited for use in industrial and outdoor environments. It also provides consistent output in ambient temperatures from –40 to 185°F and exhibits no gravitational error. Standard output is CSA approved intrinsically safe 4-to-20 mA, with 0 to 5 Vdc and CANopen also available.

FOR MORE information on the LPI sensor, call tecsis at (614) 430-0683 or visit www.tecsys.us.

If you have a wood-burning fireplace or stove, this long, cold winter may have depleted your stockpile of firewood. And if you’re like most fluid-power aficionados, you’ve dreamt of applying your knowledge to build your own hydraulic log splitter.

Most commercially available log splitters use a hi-lo pump, which is essentially two pumps in one — a high-pressure, low-flow pump and a low-pressure, high-flow pump operating in tandem. In normal operation, both pumps route fluid to the cap end of a cylinder. When a wedge mounted to the cylinder’s rod end engages the log, system pressure increases, which shifts the pump into high-pressure mode. In this mode, the high-flow pump is removed from the circuit, so only fluid from the high-pressure pump flows to the cylinder.

Reader Jean-Louis Bournival, of Vaudreuil, Quebec, proposed the regenerative circuit shown here. It uses unloading valve A set about 120 to 150 psi lower than relief valve B. The circuit provides high extension speed until the cylinder meets resistance and then automatically produces higher force at lower speed until the log splits.

Referring to the schematic, with the directional valve shifted for extension, pressurized fluid flows into the cap end of the cylinder. Fluid flowing from the rod end is blocked from returning to tank by check valve C. Instead, fluid flows through check valve D and combines with pump flow to extend the piston at high speed. When pressure in the cylinder cap end reaches the pressure setting of valve A, pilot pressure opens it, allowing fluid from the cylinder’s rod end to flow to tank. Full pressure is now applied to the piston. Of course, this circuit will perform in other high/low applications.

The Vacall division of Gradall Industries Inc., New Philadelphia, Ohio, provides superior jetting and vacuum solutions for everything from small, local maintenance — such as street sweeping — to large-scale cleanup efforts — such as the ones that progressed along the New Jersey shoreline in response to Hurricane Sandy.

Vacall officials wanted to upgrade the majority of their products to CANbus-based controls. However, they were unable to find an appropriate solution with their existing transmitters, so they implemented a product-wide replacement of wireless transmitters and receivers.

Vacall’s sweepers, catch basin and sewer cleaners, excavators, and vacuum loaders offer unique approaches to help contractors and municipalities save on repair costs and maintenance time. In the case of Hurricane Sandy cleanup, Vacall’s AllJetVac effectively cleared sewers of debris with a high-powered water jet, while an AllVac removed sand buildup from homes and businesses.

Wireless excavation control

The AllExcavate, a hydroexcavator that removes materials around water lines, sewer lines and other underground utilities, was one of Vacall’s products that benefited from the new radio remote control installation. It uses a Flex Pro handheld transmitter paired with an Enrange CAN-6 receiver — both manufactured by Magnetek, Menomonee Falls, Wis. — to manage the movements of a debris tank’s “high dump” function.

The AllExcavate’s 10-yd³ tank can be raised 76 in. above ground level and shifted 21-in. horizontally, past the end of the truck bumper and over the edge of the receiving container. Wireless controls allow for versatile functionality and safe, smooth tank movement. Improved dumping efficiency and a clearer view of the debris removal process saves time and enhances production, additionally reducing the risk of problematic spills.

Multiple benefits

With the Flex Pro and CAN-6, Vacall personnel can adjust machine operations through internal programming, thereby reducing reliance upon external operators for control parameter alterations. The 12-button Flex Pro features proportional control, which allows operators to move machines gradually to their intended targets easier, safer, and faster than with discrete control. Without proportional control, a larger “bellybox” transmitter would have been necessary, complicating operations and taking up extra space.

Both the Flex Pro and CAN-6 are compact and rugged enough to withstand harsh environments, making them ideal for potentially hazardous industrial or environmental cleanup sites. The addition of CAN-bus compatible wireless controls improves product performance, time of operation, and safety of operators during machine processes. Proportional control on the transmitters smoothed overall excavator, sweeper and vacuum movements, reducing the risk of problems during cleanup procedures.

Magnetek’s wireless control products eliminate the need for external vendors to make changes in control parameters. They also meet application specifications to reduce internal engineering, reduce time to market, and improve machine performance overall. 

FOR MORE information on Magnetek’s custom-engineered wireless communication products, call (800) 288-8178 or visit www.magnetek.com. Find out more about Magnetek’s CAN-6 and other wireless controls at IFPE Booth 81147.

What often comes to mind when people hear of demolition work is a giant crane equipped with a wrecking ball. Smaller jobs may use an excavator with grapple attachment to rip structures apart. The debris from these demolition projects must be broken down for disposal or recycling, which is where hydraulic breakers find favor.

Hydraulic breakers cycle rapidly to pulverize concrete foundations, roadways, and construction debris. For larger jobs, a breaker attachment is attached to a skid-steer loader, excavator or other machine. But when quarters are especially cramped, a walk-behind loader may be the only option.

The Toro Co., Bloomington, Minn., serves this need with its Dingo TX 525 compact utility loader. The TX 525 is available in two models. A wide track version fits through openings 42-in. wide, while its narrow-track counterpart can fit through openings only 35-in. wide.

Powered by a 25-hp Kubota diesel engine, the TX 525 features four independent hydraulic pumps — two for its hydrostatic drive, one for its bucket and loader, and one for auxiliary functions. Each hydrostatic pump is fed by a charge pump and features variable displacement to 16.9 gpm and bidirectional flow capability. Two fixed-displacement pumps deliver 6 gpm to the loader arm and bucket cylinders and 13.8 gpm to the auxiliary motor.

FOR MORE information on Toro’s complete line of compact utility loaders and attachments, call (800) 344-8676, visit www.toro.com/dingo, or visit ConExpo/ConAgg Booth 63039.

Most motion-control applications are of a critical nature — they must meet accuracy, bandwidth, or some other performance demand. The most sensible and expedient way to design such systems is to use performance requirements as the design goals at the very outset of the design process. The techniques are analytical in nature, so they require mathematical descriptions of all elements of the system. Only then can synthesis and simulation methods be applied to direct the design process toward the end result without undue trial-and-error techniques. This is how motion-control and mathematical models complement and enhance one another.

The nature of the mathematical model is dictated as much by the intended use as it is by the nature of the device being modeled. Individual modelers’ beliefs and biases have been known to influence models, too. However, most designers would agree that models fall into two broad categories: steady state and dynamic. A hydraulic motor will be modeled in steady state and analyzed through some examples of how the models can be used.

Hydraulic-motor models

The analytical schematic of the hydraulic motor has three internal leakage paths, and one internal friction-windage resistance. However, note in Fig. 1, that output is mechanical power in the form of speed and torque, whereas the input is hydraulic in the form of pressure and flow. We’ll begin by visualizing the real physical processes that the three leakage resistances represent in, say, a piston motor.

First, a direct path exists between the rotating barrel and the port plate, characterized by the laminar leakage resistance, R_Ipp. Second, there is a leakage from the high-pressure side, past the pistons and their bores, that ends up in the motor case. Another leakage component feeds the slipper faces through the piston centers and also leads to the motor case. Its leakage resistance is symbolized by R_ı1. Lastly, the same effects exist on the low-pressure side, leading to a low-pressure leakage component to case drain. It is characterized by R_ı2.

In addition, friction and windage account for a torque loss that depends on speed. It is symbolized with R_fw in Fig. 1. This completes the steady-state, high-speed, linearized mathematical model of a hydraulic motor. It can be used on any motor type, provided sufficient data exists to evaluate the leakage resistance and the friction and windage resistance.

An application scenario

Imagine a hydraulic motor has been tested at a load torque of 823 lb-in. at 2,400 rpm. The inlet supply pressure was 3,000 psi while the motor outlet and case drain were essentially at 0 psig. The case-drain flow was measured at 3.39 in.³/sec and the motor inlet flow was 82.9 in.³/sec. If the motor has a displacement of 1.88 in.³/rev, determine the values for R_ı1 and R_fw.

With outlet and case-drain ports at zero pressure, the full 3,000 psi is impressed across R_ı1, R_pp, and the ideal displacement element of the motor. First, we need to find the ideal flow, Q_I, using the well-known relationship:

We can calculate the R_ı1 coefficient directly from given data by assuming that the leakage flow is laminar and, therefore, directly proportional to pressure and inversely proportional to the resistance coefficient:

Input flow continuity requires that:

Now the port-to-port leakage resistance can be found:

To find the friction resistance, we must first calculate the ideal torque using the well-known relationship between inlet differential pressure and output torque in the ideal motor:

The measured torque was given as 823 lb-in. Therefore, the total friction torque loss is:

Because we assume that this is all viscous friction loss, and that the loss is directly proportional to speed, then:

Now the coefficients for the motor model have been evaluated. Formulas for calculating leakage resistance directly from motor efficiencies exist, but space prevents their inclusion here. Most technical data sheets on motors lack a specific value of case-drain leakage, which is necessary to evaluate port-to-case-drain resistance. The motor manufacturer must be consulted for that information.

Adding proportional control

Now consider that the same motor is being used in a circuit controlled by a proportional valve. A low-pressure shaft seal in the motor allows case drain flow to return to tank through separate plumbing. Due to valve pressure drops, pressure is 2,160 psig at the motor inlet port, 915 psig at the motor outlet port, and the motor shaft spins at 1,722 rpm. Assuming that R_ı1 = R_ı2, we will calculate case-drain flow, motor-inlet flow, motor-outlet flow, and load torque.

We’ll start with Fig. 2, an illustration of an analytical schematic that lists all the known values. Notice that the entire supply pressure is impressed across the leakage resistance (R_ı1). Therefore:

Similarly, the outlet pressure, P_b, is impressed across R₂, therefore:

The motor differential pressure is impressed across the port-to-port leakage resistance:

The operating speed is given as 1,722 rpm, therefore, the ideal flow can be found:

The total inlet flow is found using the summation of flows at the A-port node:

The case-drain flow is the sum of two components:

The outlet flow is comprised of three components:

The load torque can be found by first calculating the ideal torque: 

The load torque is the ideal torque less the loss due to viscous friction:

Now:

Summarizing, then, case-drain flow (Q_cd) is 3.475 in.³/sec; motor-inlet flow (Q_aMi) is 58.19 in.³/sec; motor-outlet flow (Q_aMo) is 54.72 in.³/sec; and load torque (T_oM) is 144.45 lb-in.

Synchronizing the speed of two motors

Hydraulic-system designers often connect two motors in series in an attempt to synchronize their speeds. In principle, this is a sound idea. In actuality, however, the degree of synchronizing is imperfect because of finite internal leakage resistances. The accompanying box illustrates a practical use of a mathematical model to quantify the degree of this nonequality of the two motor speeds.

Connecting two hydraulic motors in series in an attempt to synchronize their speeds is a sound idea. In reality, though, the synchronization is imperfect because of internal leakage resistances. We’ll now examine a scenario using a mathematical model to quantify the inequality of the two motor speeds.

Assume two hydraulic motors — each identical to that described previously — are to be connected in series and powered by a 60-in.³/sec constant-flow source. As shown in Fig. 3, the outlet port of the low-pressure motor is connected directly to tank, as are both case-drain ports. The high-pressure motor is connected to a 650-lb-in. load, but the shaft of the low-pressure motor is completely free. Both motors have a displacement of 1.88 in.³/rev; leakage resistance from each motor port to case of 885 psi/(in.³/sec); port-to-port leakage resistance of 696 psi/(in.³/sec); and torque loss from friction and windage of 0.031 lb-in./rpm.

There are four unknowns: P₁, P₂, N₁, and N₂, so four equations will be written and solved simultaneously. Note from the illustration that P₄ and P₃ equal 0. Two node equations represent the summation of flows (P₁ and P₂ nodes) and two torque summation equations (N₁ and N₂).

Flow summation at P₁:

Flow summation at P₂:

Torque summation at N₁:

Torque summation at N₁:

Substitution and linear algebra matrix are two common methods of solving four equations with four unknowns. However, the most practical method is by computer, and all popular spreadsheet programs have a simultaneous equation-solving capability. I solved these equations using the eQsolver capability in IDAS Engineering software. The results are:

P₁ = 2,537 psig,

P₂ = 186.6 psig,

N₁ = 1,716 rpm, and

N₂ = 1,802 rpm.

The solution to this problem demonstrates that there is nearly a 100-rpm difference between the two motor speeds. If we now solve the problem with the loads reversed (the upper motor is unloaded and the lower motor is loaded) we find that:

P₁ = 2,521 psig,

P₂ = 2,333 psig,

N₁ = 1,815 rpm, and

N₂ = 1,549 rpm.

This solution shows that there is nearly a 300-rpm change in the speed of the lower motor — a condition that certainly is less than ideal for the application, but without more specific information, judgments cannot be passed.

The point of this analysis is not to provide a means for achieving perfect motor speed synchronization. Rather, there is a more limited goal. First, using reasonable models of hydraulic machinery, it is possible to evaluate the consequences of implementing a given circuit concept before any hardware is even assembled. Second, circuit developers and designers can explore the endless “what ifs” that always occur at circuit design time.

The broader issue of perfect motor-speed synchronization requires closed-loop speed-control systems and will have to wait for some later discussion. Additionally, closed-loop control modeling must expand to include dynamic response because of the possibility of hunting and sustained oscillations.

Every three years the fluid-power community convenes in Las Vegas for the IFPE show, conference and related events. IFPE 2014 — International Exposition for Power Transmission is set to be the largest yet. The exposition and technical conference highlights fluid power, power transmission, and motion control. There isn’t another show in North America that brings together so many sectors of the fluid power industry.

Once again, IFPE will be colocated with ConExpo/ConAgg, one of North America’s largest construction equipment trade shows. Both events will be held March 4-8 at the Las Vegas Convention Center.

Education spotlight

Education is a key component of IFPE and this year there’s a lot on offer. More than 100 educational sessions will be held at the IFPE Technical Conference, with topics ranging from new technologies, best practices, and the latest in research and development. Conference tickets are $85 and include admission to all technical presentations, two keynote presentations, a flash drive with the conference proceedings, and certificates for continuing education.

Two keynote presentations are scheduled for the conference. On Wednesday, Lonnie Love, Ph.D., Group Leader of Oak Ridge National Laboratory’s Automation, Robotics and Manufacturing Group, is presenting on Energy Consumption in Fluid Power, where the discussion will focus on energy savings, emerging trends in manufacturing, and workforce development. Thursday, Ken Gray, Global Product Manager at Caterpillar Inc., is presenting the story behind the Hydraulic Hybrid Excavator from Caterpillar. 

Four college-level courses will also be offered. Each course is half-a-day, and after completion, certificates for continuing education are available. Attendees have a chance to complete classes on Fluid Power Systems; Sizing a Hydrostatic Transmission Using Calculations; Condition Monitoring of Hydraulic Fluids; and Design of Hybrid Systems.

The ConExpo/ConAgg will also offer a comprehensive education program with sessions emphasizing industry issues and trends, management, and applied technologies. There are 10 program tracks to help attendees locate topics of their greatest interest: aggregates, asphalt, business management, concrete, crane and rigging, earthmoving and site development, equipment management and maintenance, recycling and preservation, safety and regulations, and workforce development.

For attendees who can’t attend every session, ConExpo/ConAgg will record the education sessions, which will be available for purchase after the show.

Lots of ground to cover

More than 2,000 exhibitors taking over 2 million net sq ft of exhibit space will mean a lot of walking. More than 400 companies will be exhibiting at IFPE alone. This year’s events also feature navigational improvements to benefit everyone. A superior shuttle service, an enhanced mobile navigation app, and on-site guides will help move attendees through the showroom floor more efficiently.

Look for the five IFPE pavilions. Three international pavilions will showcase China, Taiwan, and Italy. Two additional pavilions highlight the Power Transmission Distributors Association and sensors. These pavilions are designed to provide a concentration of similar booths and bring together users and producers of components from all over the world together.

Free fluid-power seminars

New this year, Hydraulics & Pneumatics has organized a free series of fluid-power seminars. The series will give attendees a better understanding of the operation and maintenance of hydraulic and pneumatic systems. Twelve sessions are included in the series with topics such as best practices, environmental impacts, mobile hydraulics, troubleshooting, and more.

One registration covers entrance to all exhibits at IFPE and ConExpo/ConAgg. Register at www.ifpe.com. Attendees can use the site’s interactive “show planner,” which includes show maps that are searchable by hall/lot location, booth number, company name, and type of product. The show planner will also be available as a free smartphone mobile application.

VISIT www.hydraulicspneumatics.com to access our December and January issues for complete education topics, schedules, and details or visit bit.ly/1ju3g2i.

When compared to other motion-control methods, there are many reasons to consider powering machines with pneumatics. Unlike electromechanical systems, where the electric power source is typically located right at the actuator, air compressors for pneumatic systems can be located some distance from the cylinder. This means the air cylinder can often be much smaller and lighter compared to a mechanical actuator like a ball screw and its electric motor.

Further, air’s compressibility offers advantages in applications that can benefit from some “give” in the motion. This makes pneumatics attractive, for instance, in packaging systems where care must be taken to avoid damaging fragile products. 

Also, because wear in fluid-power systems is less likely to directly affect the accuracy of the motion, servopneumatic systems often require less maintenance when compared to electromechanical systems. This reduces downtime and increases machine productivity.

Another advantage of pneumatics is that fluid-power sources (compressors and pumps) often need only be sized for the average load, whereas electric motors must be sized for the maximum load that will be applied to the system.  In low-duty-cycle pneumatic applications, such as systems that move slowly or sporadically, an air tank can store energy and efficiently provide high peak power while using a small compressor. Also, one compressor can serve multiple actuators, which is generally not possible with motor-driven axes. These advantages make pneumatics attractive for many robotic and material-handling applications.

In addition, fluid-power actuators can apply constant pressure to a load without consuming a significant amount of energy. By comparison, applying constant force or holding pressure with electric motors would typically require complex gearing or braking mechanisms to prevent excessive power consumption and overheating.

And compared to hydraulics, pneumatics is clean and, thus, preferable for use in food-handling systems where oil contamination must be avoided.

That said, however, pneumatic power has had some inherent drawbacks compared to other power sources. The compressibility of air, though an advantage in some applications, makes pneumatic motion more difficult to precisely control than “stiff” mechanical-motion systems. And a typical pneumatic valve supports only two positions during operation: fully open and fully closed. This coarse control is acceptable for some motion systems, but other applications need to move with more finesse.

High-performance pneumatics

With effective design, servopneumatic systems can generate smoother and more precise motion than is possible with standard pneumatics, often on par with electromechanical systems.

The key is to use a motion controller with capabilities specifically designed for pneumatic control, and to pair it with other high-performance components. These include:

• Low-static friction cylinders. When selecting cylinders for high-performance applications, it is also important to make the ratio of piston surface area to cylinder air volume as high as possible.
• Servo-quality proportional valves. Such valves can precisely control the pressure on each side of a cylinder and should be used in place of pressure-relief valves or two-position “bang-bang” valves. Fluid-power-enabled motion controllers are capable of directly driving servovalves.
• Feedback sensors. Magnetostrictive displacement transducers (MDT) are often used to provide position information to the motion controller. Pressure transducers mounted in the cylinder on each side of the piston allow the controller to calculate pressure differential and, thus, the force that the pneumatic actuator exerts.

The “servopneumatic setup” graphic shows typical connections between the motion controller and the cylinder, valve, and transducers.

High-performance motion controllers can simultaneously control several motion axes, moving independently or in relation to one another. Some can even select, on the fly, between multiple feedback devices to extend their range of operation (if the feedback devices have different ranges of sensitivity), or protect against the adverse effects of feedback device failure (if redundant feedback devices are used). Delta Computer Systems’ RMC family of motion controllers, for example, can tightly coordinate up to eight motion axes simultaneously and handle a wide range of feedback options, including mathematically calculated feedback values.

Advanced control concepts

The physical differences in pneumatics versus hydraulic and electromechanical systems place different demands on the controller. If the electropneumatic motion controller used for a specific application is only capable of closing the loop with a simple PID algorithm, then the response or bandwidth of the system will be limited by the system hardware’s damping factor and natural frequency. Because pneumatic systems can be particularly “springy” compared to mechanical or hydraulic systems, a regular PID control loop that depends on position feedback alone may not be able to keep up with the reaction of a pneumatic system to stimuli like changes in load or speed. Overshoot of a target position or even oscillations can result.

To combat these effects, controllers use advanced control techniques such as active damping that consider accelerations or forces acting on the system. This sometimes requires adding secondary transducers, depending on the type of active damping, in addition to the primary position feedback.  Active damping dramatically reduces oscillations in industrial applications and provides the controlled, compliant motion necessary for high-performance pneumatic machines.

In other cases, the motion controller can use model-based control to provide mathematically enhanced “feedback” for a PID + double-derivative gain (D2) control loop. Higher derivative gains sometimes require an output filter to minimize high-frequency noise in the drive output. Predictive feed-forward gains are not always effective in a pneumatic system, and tuning a servopneumatic system can be challenging. But such advanced control and tuning methods should be used to damp out unwanted motion effects before they arise.

Active damping and PID + D2 with model-based feedback are two strategies that can be applied if the motion controller is capable of processing advanced mathematical functions in closed-loop control. But determining parameter and gain values for control loops incorporating multiple settings can be complex. A solution is to use a motion controller that incorporates automated tuning tools.

Tools simplify design

Such tools build a mathematical model of how the system responds to a stimulus and calculate optimal control-loop parameter gains that produce the best response. An example of such an automated tool is Delta Computer Systems’ Tuning Wizard. Another useful tool for system optimization is Delta’s Plot Manager, which graphically displays how a system’s actual motion compares with target motion profiles. When a system is tuned correctly, the actual motion profile precisely matches the target.

Another issue to consider when selecting control-system components is ease of networking. Modern machines pass control instructions and process data via industry standard networks such as ProfiNet or EtherNet/IP. Electropneumatic motion controllers with standard communication interfaces are easy to incorporate into machines by designers who want to use best-in-class components.

More precise control over the pneumatics can increase machine productivity and, by enabling smoother motion, cut maintenance costs. Of course, pneumatic systems are not the only designs that can benefit from advanced controls. Hydraulic systems can also take advantage of recent developments in control algorithms and tuning tools.  With these innovations, the time it takes to tune a system can routinely be reduced by an order of magnitude or more, compared to manual “trial-and-error” methods. And even better, the end product operates with precision that is often attributed to mechanical motion alone.

FOR MORE information on Delta Computer Systems and advanced motion control, visit www.deltamotion.com.

Anyone who uses compressed air will, at some point, find liquid water in the air distribution system. This can be anything from a nuisance to a serious problem, depending on the application. For example, if water might corrode equipment or introduce bacteria, removing it is critical.

Compressed air typically contains water as both liquid and vapor. Because removing it carries a cost, it’s important to define how dry the air must be for a given application and specify the right equipment to produce this result. First, though, it’s helpful to understand the source of water in a system.

A compressor draws in ambient atmospheric air, which includes water vapor. Compressing the air raises its temperature, which increases the air’s vapor holding capacity as well as its dewpoint (see “Details On Dewpoint,” p. 78). Any subsequent cooling of the air (such as by an aftercooler) causes condensation. The process of “drying” compressed air can range from trapping condensed water and preventing additional condensation to removing all the water present using filters and dryers.

Compressed-air systems

To put this in context, consider the components that make up a typical air-distribution system (Fig. 1). A compressor, the heart of the system, typically compresses air to about 100 psi. Air flows from the compressor to an aftercooler, which condenses up to 75% of the water vapor. Compressed air leaving the aftercooler is saturated. Any further cooling produces condensation. For example, air could be further cooled after exiting the aftercooler if air lines are exposed to unheated rooms. This cooling below the compressed air’s dewpoint is the source of additional water that users see in their pneumatic systems.

After exiting the aftercooler, air travels to a receiver, which tends to further cool the compressed air, condensing out more liquid. Most liquid is removed through an automatic drain. However, compressed air exiting the receiver still includes liquid droplets of water, water vapor, and oil (from compressor lubricant and leaking seals), so high-efficiency coalescing filters are needed downstream from the receiver.

Coalescing filters

Coalescing filters remove contaminants and help protect downstream dryers, which are sensitive to liquid contamination. At a minimum, a single-stage, high-efficiency coalescing filter rated at 93% efficiency at 0.01 μm is adequate prefiltration for refrigerant air dryers and general pneumatic equipment.

However, two-stage, high-efficiency coalescing filters ensure complete liquid removal, assuming no further cooling beyond the filter. When instrument-quality air is needed, or a desiccant air dryer is required, it is good practice to install a two-stage filtration system near the point of use. A two-stage system has a prefilter such as a Balston Grade DX (Fig. 2), that filters out larger droplets of water and oil and a polishing filter such as a Balston Grade BX, rated 99.99% at 0.01 μm, that filters out submicron-size droplets.

Many kinds of equipment can be protected using coalescing filters alone. Yet despite upstream processing of the air, water vapor typically remains in suspension throughout the system. Sensitive equipment such as precision air-bearing tables for laser cutting or parts inspection, for example, requires extremely clean, dry air. In these cases, it’s often necessary to add an air dryer downstream from the filters.

Dryer types

A dryer removes some or all traces of water vapor before compressed air reaches the critical end-use point. Several different types are available.

Desiccant dryers deliver air at consistently low dewpoints, typically –40°F (–40°C) or less. The technology is a good choice when compressed air will be exposed to freezing conditions.

Desiccant dryers generally consist of twin towers of desiccant material that adsorbs water vapor (Fig. 3). Compressed air passes through one tower of desiccant until it’s saturated. Airflow then switches to the standby (dry) tower while the first bed is regenerated, driving captured water from the desiccant, with heat or a portion of dry air from the active tower. Heated and nonheated desiccant dryers serve the same purpose. They just use slightly different approaches.

Heated desiccant dryers require a great deal of electricity to operate. In contrast, heatless desiccant dryers don’t depend on electricity for drying, though they do consume and exhaust a small portion of the compressed air. In some cases, heatless desiccant dryers can be pneumatically controlled, which makes them suitable for explosion-proof installations.

Membrane dryers offer a range of drying capabilities to about –40°F (–40°C) dewpoint. Like desiccant dryers, this suits them for sub-freezing environments.

Membrane dryers (Fig. 4) consist of bundles of hollow membrane fibers, each permeable only to water vapor. As compressed air passes through the center of these fibers, water vapor permeates the walls of the fiber, and dry air exits from the end of the membrane dryer. The module redirects a small portion of dry air (regeneration flow) along the outer surface of the membrane fibers to carry away the moisture-laden air, and it is released harmlessly to atmosphere.

Membrane dryers have no moving parts and require no electricity, so they operate at a low cost. They only need their prefilter cartridge changed out, typically once a year. These dryers are ideal for critical end-use point applications, remote areas, and explosive environments. 

Refrigerated dryers work by cooling air to low temperatures and thereby condensing out much of the water vapor. Well-designed refrigerant dryers can produce air with dewpoints to approximately 35°F (2°C). Most operate at a range of 35 to 40°F (2 to 4°C) dewpoint.

Sophisticated refrigerant dryers remove the heat from the inlet air and use it to reheat the outlet air. Dry air returns to the air line at reasonable temperatures. This process prevents condensation when air lines are exposed to cold surroundings. Self-contained refrigerant dryers use fans to cool the refrigerant condenser and automatic controls to adjust heat-exchange performance to the application requirements. These systems keep the delivered air at a constant humidity or dewpoint.

Specifying a dryer

When considering a dryer for a compressed air installation, designers can keep several guidelines in mind.

First, if compressed air will be frequently exposed to temperatures colder than ambient conditions, and instruments or equipment is sensitive to moisture, it is wise to install a dryer. A system that includes just an aftercooler and coalescing filter could lead to problems with condensation downstream from the aftercooler. The air will still be saturated with vapor, which is likely to condense when the ambient temperature is lower than the compressed-air temperature.

Next, beware of overspecifying a dryer. For example, drying the entire compressed-air supply in a plant to dewpoints below –40°F (–40°C) is wasteful and unnecessarily expensive. It is more sensible to segment the compressed-air supply by application, so each end-use point gets only the level of dryness that’s required.

Similarly, beware of underspecifying. Damage due to wet air is costly in terms of maintenance time, replacement parts, downtime, and lost product. Design a drying system to meet specific needs.

Leverage the “drying” effect of pressure reduction in applications that use air at pressures lower than that of the main compressed air line and that can tolerate some water vapor.

Specify membrane dryers for parts of a system that require dewpoints of 35 to 42°F (2 to 5°C) and flow rates up to 600 scfm (17 Nm³/min).

Finally, consider using membrane dryers for instrument-quality air, air exposed to freezing temperatures, and water-sensitive applications that require flow rates ranging up to 100 scfm (3 Nm³/min). Typically, compressed air with a dewpoint of –40°F (–40°C) is reasonable for these water-vapor-sensitive applications.

The right selection

Drying compressed air to the appropriate dewpoint is important. However, not all applications require ultralow dewpoint air. It is plausible to use a two-stage, high-efficiency coalescing filter system that’s installed directly at the inlet of critical end-use instruments or machines, where all liquid contaminants can be removed just prior to entering the equipment.

An air dryer or coalescing-filter system is best selected by an educated user, or with the aid of an experienced application engineer. It’s important to understand the moisture level each application can tolerate and balance the cost of the drying and filtration system with the required purity level.

ALLAN FISH is the product manager of the Parker Hannifin Corp. Filtration and Separation Division, Haverhill, Mass. For more information on air dryers from Parker’s Filtration and Separation Division, visit www.balstonfilters.com.

The Work Truck Show is scheduled for March 5-7 in Indianapolis, in conjunction with the 50th annual NTEA Convention. The show features new products, offers training sessions, and provides access to technical engineering representatives from exhibiting companies, including a number of hydraulic and pneumatic suppliers.

As the largest work truck event in North America, the show gives attendees an opportunity to interact with thousands of industry professionals; meet with current suppliers or customers; get answers to technical questions; and socialize with industry peers.

The event showcases more than 500,000 sq ft of vocational trucks and equipment, including the latest innovations for chassis and truck bodies, cranes and aerial devices, snow and ice-control equipment, liftgates, and more.

Additionally, there are more than 60 educational programs on key topics such as truck design, industry trends, regulatory compliance, and OEM updates.

The Green Truck Summit also is slated for March 4-5, providing insight on the application of green technologies.

Visit www.ntea.com/worktruckshow for more details and to register.

Water was the first fluid ever used as a power transmission medium — the earliest water-hydraulics applications date to 2,000 years ago. Of course, modern water-hydraulic systems differ greatly from historical applications, thanks to an influx of new design, material, and control technologies.

The 1990s saw many countries around the world devote extensive research and development toward water hydraulics. R&D cooled somewhat at the onset of the new millennium, but it’s bouncing back due to rising concerns about the environment and global climate change.

Sustainability

Questions surround the sustainability of water hydraulics technology. It hinges on two main factors: pressure-medium life cycle and energy efficiency. When comparing sustainability of various pressure-medium alternatives, all processes related to the supply chain must be considered. For example, in the oil industry, this means all processes related to drilling the oil, transportation, refining, marketing, delivery, usage and disposal.

In this case, the comparing supply chains for oil against water reveals stark differences. Water is more readily available, and it requires minimal purification and treatment processes. Oil’s supply chain, on the other hand, is long, requires significant capital investments, and presents an environmental hazard. Furthermore, oil must be packed into barrels, containers, cans, etc., while water is usually available from the tap.

On the other hand, microbiological growth becomes concern in water-hydraulic systems, adding costs for maintenance and service. Antimicrobial additives can prevent microbial growth, once again adding to overall cost. Still, the cost benefits of easy storage and less frequent fluid changes outweigh the negatives.

Comparison of oil and water in terms of overall energy efficiency is somewhat more complex. Water hydraulics uses stainless steel and similar materials to resist corrosion of components. Furthermore, certain design features can be complicated to manufacture, and small production quantities increase energy consumption of production per produced component. On the flip side, water undergoes lower pressure losses than oil, which is a major benefit for efficiency, especially with large flows and long pipes.

A system’s basic design and control principle also plays a big role in energy consumption. Unlike oil hydraulics, water hydraulics must rely on different methods to improve overall system efficiency due to the limited availability of variable-displacement pumps and limited controller options.

The easiest solution is to use unloader and relief valves just like those employed in oil hydraulics (before variable-displacement pumps became commonplace for oil-based systems). In some cases, the ever-improving controllability of modern ac variable-frequency drives makes it possible to use pump-speed control to achieve the control functions derived from variable-displacement pumps in oil hydraulics. One future option involves the application of digital hydraulics technology to achieve accurate and fast load-control tasks with optimized energy consumption.

Market Study Revelations

Students at Tampere University of Technology (TUT), Finland, conducted an international market survey of water-hydraulics component and system manufacturers in the spring of 2013. Despite the rather narrow sample size, it revealed developing trends within the water-hydraulics market. For instance, 75% of the respondents said water-hydraulics sales have been increasing over the last five years, and 87.5% expect further growth during the next five years. This is good news, considering the development of the whole technology area.

What is the most important reason for using water hydraulics? The number one answer was safety (fire resistance), for people and the environment. Therefore, Europe, Asia, and the U. S. stand to gain the most by more widespread use of water hydraulics. Additional responses indicate a nearly even split between use of HF-A solutions and pure water systems as the most prevalent. However, many pure water systems are of the open high-pressure variety, which significantly affects distribution. Meanwhile, HF-A systems dominate for power transmission applications.

In terms of power, system deliveries distributed quite evenly from 10 kW to more than 100 kW. However, power rating of systems was somewhat concentrated at both extremes, with fewer falling within the 50‑kW range. Lower-power systems tend to operate within a pressure range of 50 to 160 bar, whereas higher power systems operate at pressures exceeding 300 bar.

What improvements are needed? Respondents wished to see developments to improve control valves, materials, seals, and reliability, as well as to reduce manufacturing costs. More than 70% of the responding companies plan to put more effort into product development in the future.

What is the top application for water hydraulics? The metal industry ranked number one (50%), with water treatment, mining, and the oil and gas industry also well represented.

One of the more common water-hydraulic applications today is the waterjet cutting system for the paper industry, where open-end systems cut paper lines in paper machines. Typical pressures range from 800 to 1,500 bar, and flows from about 1 to 5 lpm.

Figure 1 shows a direct-drive triplex pump developed by Hytar Oy. It has 900-bar maximum pressure with a flow rate of 4.7 lpm at 1,200 rpm. It suits hydrostatic pressure testing, medium-pressure waterjet cutting, and high-pressure washing systems. The pump can be used with pure water and low viscosity fluids with 40-μm filtration. Rotational speeds range from 100 to 1,200 rpm continuous; 0 to 1,500 rpm temporary.

The All-Important Pump

One clear trend has emerged within the world of water hydraulics and its development during the decades: a division between open systems using pure water and closed power-transmission systems that use HFA fluid or other water-based fluids. This has given rise to the term high-pressure water systems or solutions — and with justification.

Most of today’s high-pressure water pumps are in-line piston units driven by an oil-lubricated crankshaft mechanism. Much less available are water-lubricated pumps usually of axial-piston design with a rotating cylinder group and fixed swashplate.

Because of water’s limitations as a pressure medium, water lubricated axial-piston pumps often are complicated to design and manufacture. Nonetheless, certain features and characteristics of axial-piston pumps become assets for water-hydraulics applications, namely high efficiency and high power density.

Variable-displacement axial-piston pumps for water hydraulics are quite scarce. The Water Hydraulics Co. Ltd., Hull, England (bit.ly/1eOphW3), the lone manufacturer of these pumps, offers only two displacements (70 and 225 cm³/rev). This limits applicability of water hydraulics, especially in higher-power applications that would have to sacrifice overall system efficiency because of the limited pump controllability.

The key issue surrounding water lubricated axial-piston pumps concerns the design of, and materials used for, various water-lubricated sliding interfaces inside the pump. The most recent comprehensive study related to this area comes from a dissertation provided by Dr. Markus Rokala. In his dissertation, Rokala focused on slipper behavior during operation, slipper behavior during swashplate turning, and especially the impact of the slipper deformations in water-hydraulics axial-piston pumps.

Rokala’s goal was to find methods that achieve a higher power density for axial-piston pumps in water-hydraulic systems. This meant better components were needed to widen the range of applications for water hydraulics. He studied two different basic structures of slippers with different material combinations. He found that slipper behavior can be predicted with sufficient accuracy using a simulation model. This model was based on fluid structure interaction calculations, basic theory, and measurements.

ultrahigh-pressure systems

The hydraulically driven pressure-intensifier pump is the predominant pump technology in ultrahigh-pressure applications, such as water-jet cutting, or in demanding environments, especially for transfer-barrier pumps used the steel and forging industries. It’s also become a popular choice for mobile high-pressure water systems, such as high-pressure cleaning applications, dust suppression, and hydrodemolition. Furthermore, it’s proven to be a versatile technology for mobile applications, as evidenced by water hydraulic pumps from Dynaset Oy, Ylöjärvi, Finland (bit.ly/1aOAuX6).

Most of today’s pressure intensifiers are of the reciprocating type, featuring dual water pistons. Some multiple-piston rotating units also are available. Perhaps their biggest advantage is simple construction. On top of that, power-to-weight and volume ratios and efficiency can be very lucrative in spite of the oil hydraulic primary drive. Oil hydraulic primary drives offer some advantages in control, such as power control and load sensing, something not typically found in water-hydraulic systems.

Digital Water Hydraulics

Digital hydraulics offers another way to achieve different controls in fluid power. Lots of research has gone into the implementation of digital hydraulics in oil hydraulics, but it’s also suitable for water hydraulic systems. In fact, about 15 years ago, TUT first ran into digital (discrete) controls when researching low-pressure water hydraulics. Digital hydraulics helps further the cause of water hydraulics because it replaces proportional and servovalves, which are costly, and it’s difficult to find what you need.

The most basic approach is to use simple three or five-state controls with multiple on-off valves. Precision controls with greater complexity can be established by including more-sophisticated control algorithms and more valves. However, no valves are available yet, particularly for digital water hydraulics, thus restricting system design to whatever valves can be found in the market.

Water systems could benefit greatly from the design of a digital control unit. Research has proven that digital control increases the controllability of water systems.

KARE T. KOSKINEN is professor, and Jussi Aaltonen, project manager, both with the Department of Mechanical Engineering and Industrial Systems at Tampere University of Technology, Finland.

Situated on the border of Georgia and Florida is the Jim Woodruff Lock and Dam. The dam impounds Lake Seminole, producing hydroelectric power, and its single lock provides navigable access to the Chattahoochee River.

Hydradyne LLC, Tampa, Fla., recently completed the design, fabrication, and installation of the new hydraulic systems at the dam. Construction of the lock and dam began in 1947 and was completed in 1957 by the U. S. Army Corps of Engineers. The dam feeds a hydroelectric power plant containing three turbines with a combined rated output of 36,000 kW.

The dam’s original hydraulic system consisted of one central power unit located on the second floor of the northeast tower and two hydraulic operator stations on the east wall. The original hydraulic power unit served eight cylinders; each of four operates a miter gate, and the other four operate two upstream and two downstream water valves, which fill and drain the lock. Considering the fact that the lock chamber is 82-ft wide by 450-ft long with a maximum lift of 33 ft, a tremendous amount of welded pipe was installed to interconnect all system assemblies. Tunnels were constructed under both ends of the lock in order to run the hydraulic lines to the west-wall machinery.

The new system design consists of four identical hydraulic power units placed at each corner of the lock and two stainless-steel electric operator consoles positioned on the east wall of the lock facing the water. Each power unit operates one 12-in. bore miter gate cylinder and one 11-in. bore water valve cylinder. Because the water valves were designed to allow a water rise rate of 10.25 fpm, continuous visual contact with boaters in the lock was mandatory. Another desired feature was to include redundant controls mounted on the front face of each power unit enclosure with a hinged, lockable stainless-steel cover. The cover protects the controls from the environment and can also prevent someone from operating more than one control station at the same time.

The power units were designed for outdoor service in all weather extremes. The top surface of the 250-gallon reservoir has a 5° slope to prevent water ponding. An immersion heater in the reservoir was sized to maintain oil temperature at 70°F during the winter months. The reservoir also contains magnetic separators, a level and temperature gauge, low oil-level switches, a dual-setpoint temperature switch, pump-suction shutoff valves, suction strainers, and desiccant breathers. Two Parker axial-piston pumps, a duplex high-pressure filter, and an in-tank return filter provide system redundancy. A drip pan with drain valve was also included.

Control Center

Each of the six operator control panels also contains a keyed switch that allows the operator to select “off,” “remote,” or “local” mode providing an additional safety lockout feature. The operator would start one of the redundant west-wall and east-wall pumps and then operate the gate or water-valve cylinders in manual or automatic mode. In manual mode, the operator manually selects fast or slow speed at any time during the sequence and holds down the appropriate pushbutton. In automatic mode, the operator would momentarily depress the gate or valve open or close pushbuttons to initiate a programmed sequence. Four magnetic proximity switches were mounted along each cylinder mechanism to provide position feedback. In automatic mode, the gate or valve cylinder starts at slow speed, accelerates to high speed, slows down, and then stops at the full open or closed position.

The control panels also monitor high oil temperature, low oil level (warning and shutdown), and status of the high-pressure and return-line filters. Since differential pressure switches on filters operate only while fluid is flowing, the PLC was programmed to lock in the filter indication lights until the operator installed a new filter element and depressed a reset button. An emergency stop palmbutton was also included on each operator panel.

A new motor-control center was installed to provide power distribution to the hydraulic units. Each power-unit enclosure contained pump-motor starters, an immersion heater contactor, a 60-A transformer for external lighting, a 30-A welding receptacle, a control-voltage transformer, and a PLC. Each electric motor was provided with encapsulated windings and winding heaters. System communication was accomplished using an Ethernet/IP fiber-optic ring network. It was imperative that logic be transferred between the power-unit PLCs for control and safety interlocks. Allen-Bradley produced the tag protocol that was utilized for the logic transfer.

Custom Manifold

A custom manifold contained all valving required to operate the miter gate and water valve cylinders and included: flowmeters, directional-control valves, counterbalance valves, cylinder-port relief valves, pilot-operated check valves and a high-speed/low-speed circuit. The high-speed/low-speed circuit consisted of a low-flow, pressure-compensated flow-control valve and a full-flow normally-closed DIN-style solenoid valve. When the high-speed valve is energized, full pump flow bypasses the flow control allowing full cylinder speed. Orifices in the DIN valve allowed smooth transition from full speed to low speed. Synchronizing two opposing gates during high speed was accomplished by visually adjusting the pump maximum volume stops.

The rear face of the manifold contained four-bolt flange ports for the cylinder connections. New stainless-steel welded pipe was installed between each manifold and the cylinders in the existing concrete trenches. Two stainless-steel ball valves at each cylinder location were provided to isolate the cylinder and a third bypass ball valve allowed the new pipe to be flushed prior to commissioning of the system. The manifold also contained several pressure test ports for system monitoring and evaluation.

Finishing Up

The miter gate cylinders and water valve cylinders were the only components used from the original system. During installation of the new hydraulic system, the cylinders were removed from the lock and sent to Hydradyne’s facility for teardown and inspection. Cylinder barrels had scoring and rust, the chrome rods were pitted, and several cylinders contained 50 years’ worth of contamination. The cylinder barrels were honed, the rods were rechromed or replaced, new cast-iron piston rings were installed, and all of the seals were replaced.

Prior to shipment to the job site, all four systems were hydraulically and electrically interconnected at Hydradyne’s facility to conduct a complete functional shop test. Onsite system commissioning included pipe flushing, hydrostatic testing, oil particle and water-content analysis, as well as complete functional system testing. 

BOB NASCA is National Systems Engineer for Hydradyne LLC, Tampa, Fla., (www.hydradynellc.com). Nasca is the author of the book, Testing Fluid Power Components.

When hydraulic or pneumatic lines connect to a moving machine component, there are several ways to accommodate the motion. While the easiest is to simply allow slack hose, this method can lead to excess flexing, premature hose wear, and damage from pinching or exposure to other hazards. Hose reels are another possibility, but generally they are useful only for single or dual lines and may not accommodate longer travel distances or larger hose sizes easily. Another approach that might prove better is to use a cable and hose carrier that forms a flexible shield for multiple lines, preventing them from tangling, and paying out the hose with a smooth, rolling action.

Hose carriers can be divided into four basic types: metal link, metal tube, nonmetallic link, and nonmetallic tube. Each type is best suited to a different combination of application parameters, although the choice is not always clear-cut.

Metal-link carriers are simply parallel side links joined by crossbars that accommodate the hoses. Pivot pins and stops allow the links to travel through a predetermined arc. These designs are best for low-speed, heavy-load applications, such as machine tools.

Enclosed metal carriers are formed with small convolutions to provide better protection against chips, weld spatter, and other debris. Because carriers of this design are not limited by individual links and with their distinct travel arcs and stops, they also can operate at higher speeds, an advantage in applications such as robotics.

Where greater weight and hose-carrying capacity for longer travels are needed, nonmetallic link carriers can handle higher speeds and provide greater width and carrying capacity. This type leaves hoses open for easy inspection, but does not protect them from abrasion and debris.

Nonmetallic tube carriers are the best choice for applications that require fast travel speeds, but also require protection from outside elements. Few of the lines between parameters are clearly drawn, so it is best to begin working with a hose carrier manufacturer early in the design of any equipment with hydraulic or pneumatic lines that connect moving parts. This allows greater flexibility in choosing the hose-carrier design that provides the best combination of features for the application.

Here are some general guidelines for making a preliminary carrier selection. In terms of size, the maximum practical width for an enclosed metal tube carrier is about 6 in. Very small sizes, as well as larger sizes, are easily handled by nonmetallic designs. Nonmetal carriers are molded from fiber-reinforced plastics, which provide high strength per unit weight; however, at about one-fourth the strength of steel, these materials are not practical when combining large widths, long travels, and heavy loads.

These factors combined can help determine the final choice. For example, a low-speed application with moderate particle exposure probably calls for a metal-link design. A combination of higher speed, coupled with the presence of hot welding or grinding spatter signals the need for a metal – or specially designed heat-resistant plastic-tube type carrier. A high-speed application with the need to monitor hoses for leaks calls for an open, non-metallic design, particularly with a large number of hoses. A high-speed application that also required corrosion resistance, such as a car wash or machine with heavy coolant spray, would be a logical place for nonmetallic tube.

ELLEN RATHBURN is a Technical Copywriter at igus inc., East Providence, R. I. For more information, call (401) 438-2200 or visit www.igus.com.

A company that fabricates oil-field pipes starts with flat steel, rolls it into a round tubular shape, and simultaneously welds the inside and outside surfaces of the joined ends. Tooling removes excess weld material, creating a round pipe that actually looks like seamless pipe. A cutoff station then cuts the pipe coming off the production line to 21-ft lengths. When 12 cut pieces of pipe are collected in a saddle, a hydraulic cylinder quickly extends and dumps all 12 pieces onto a conveyor that takes them to a banding station.

The schematic shows the dump cylinder, control valves, and hydraulic power unit, which is about 50-ft away from the cylinder. The cycle time for the cylinder is quick, and once the gas pressure in the accumulator reaches 2,000 psi, the directional valve shifts to dump the batch of pipes. Again referring to the schematic, flow-control valves are mounted close to the cylinder, and the directional valve is mounted on the power unit.

The dump cylinder started failing after 1 to 1½ months of running two shifts, five days a week. The repair shop reported contamination and dirty, overheated oil as the problem. However, temperatures at the power unit do not exceed 135°F and the oil samples show an acceptable ISO cleanliness code for the components.

Any idea what was causing the problem and how to fix it?

ROBERT J. SHEAF JR., is founder and president of CFC Industrial Training, a Div. of CFC Solar, which provides technical training, consulting, and field services to any industry using fluid-power technology. Visit www.cfc-solar.com for more information.

Years ago I browsed through an annual report from Philip Morris Tobacco Co. It had all the usual pretty pictures, including a shot of the board of directors standing around a long conference table. This was nothing unusual, but each member was holding a cigarette and had an ashtray in front of him or her. I doubt that every board member smoked, but they had to wear their game faces for the annual report photo.

I was reminded of this the other day when I went to the optometrist for a new pair of glasses. It’s a big place (for an optometrist’s office), with probably about 20 employees, all of whom were wearing glasses — every one. I asked the receptionist if they were instructed to wear glasses, even if they didn’t need them. Just like the smoking executives at Philip Morris, I figured these employees had their game faces on to help promote the business.

In a way, I have my game face on in the accompanying picture — H&P shirt on, standing in front of a mobile hydraulic system. When IFPE arrives in a few weeks, I’ll be wearing my H&P shirt and IFPE ConExpo/ConAgg badge with H&P lanyard to complete the game face. But not quite. I’ll be chairing sessions 14 and 25 (Thursday and Friday mornings, respectively) at the IFPE Technical Conference, so a “Session Chair” ribbon affixed to my badge will fully complete my game face.

The anticipation of IFPE and other events about to be held in Las Vegas reminds me of the recent Super Bowl. Excitement builds each day until Super Bowl Sunday finally arrives. After a weekend of hoopla, it’s all over, except for celebrations by the winning team and its fans. The difference with IFPE and ConExpo/ConAgg is that once it’s over, you can bet there will be lots of follow-up work to be done. Not only that, but it’s a sure bet on who the winners will be: all those who attend. But if you can’t attend, we have extensive coverage in this issue and on our Web site, so you shouldn’t miss a single play.

The following is a list of all manufacturers who provide product information and specifications in our Designer's Guide. Advertisers in our January 2014 issue are in bold. Click here for a complete list of all Designer's Guide charts, which are a collection of specifications for a variety of popular categories of fluid power products and services. Charts and index listings were prepared from information supplied by those companies directly to the editors of Hydraulics & Pneumatics.

A

A and A Mfg. Co. Inc., (262) 786-1500, www.gortite.com

A&R Hydraulics, (586) 756-2810, www.arhyd.net

AAA Products International, (214) 357-3851, www.aaaproducts.com

AAH Fluid Power Inc., (586) 307-8011, www.aahfluidpower.com

Accro-Seal, a Kalplas Co., (616) 649-1014, www.accroseal.com

Accuflex Industrial Hose Ltd., (313) 451-0080, www.accuflex.com

Accumulators Inc., (713) 465-0202, www.accumulators.com

Ace Controls Inc., (248) 476-0213, www.acecontrols.com

Adaconn + Inserta, (215) 643-1900, www.adaconn.com

Adsens Technology Inc., 18310 Bedford Cir., City of Industry, CA 1744-5971, (626) 854-2773, Fax:(626) 854-8183, sales@adsens.net, www.adsens.net

Advance Automation Co., (773) 539-7633, www.advanceautomationco.com

Advanced Control Technology, (952) 882-0000, www.actsensors.com

Advanced Machine & Engrg. Co., (815) 962-6076, www.ame.com

Advanced Motion Control Inc., (860) 859-1650, www.amcct.com

Aggressive Hydraulics, (763) 792-4000, www.aggressivehydraulics.com

Air Systems Products Inc., (716) 683-0435, www.airsyspro.com

Air-Mite Devices Inc., (773) 286-3393, www.airmite.com

Air-Vac Engineering Co. Inc., (203) 888-9900

Air-Way Mfg. Co., (269) 749-2161, www.air-way.com

AirCylindersDirect.com, (866) 404-5300, www.aircylindersdirect.com

Airoyal Mfg. Co., (973) 838-0371, www.airoyal.com

Airpot Corp., (203) 846-2021, www.airpot.com

Airtrol Components Inc., (262) 786-1711, www.airtrolinc.com

AKG Thermal Systems Inc., (919) 563-4871, www.akgts.com

Alfa Laval, (866) 253-2528, www.alfalaval.us

Alkon Corp., (419) 333-7000, www.alkoncorp.com

Allenair Corp., (516) 747-5450, www.allenair.com

Alliance Plastics, (814) 899-7671, www.allianceplastics.com

Allied Metrics , (973) 827-8280, www.alliedmetrics.com

Allied Witan Co., (440) 237-9630, www.alwitco.com

Alloys & Components Southwest, (214) 637-9301, www.alloysandcomponents.com

Almo Manifold & Tool, (989) 984-0800, www.almomanifold.com

AltaFlo, (973) 383-0544, www.altaflo.com

Alumi-Tec Inc., (800) 327-7558, www.alumitecmanifolds.com

Amalga Composites, (414) 453-9555, www.amalgacomposites.com

American Grippers Inc., (203) 459-8345, www.agi-automation.com

American High Perf. Seals, (412) 788- 8815, www.ahpseals.com

American Industrial Heat Transfer, (800) 338-5959, www.aihti.com

American Ring & Tool Co., (440) 498-3730, www.americanring.net

Ametek Automation & Process Technologies Div., (248) 435-0700, www.ametekapt.com

Ametek, U.S. Gauge Div., (215) 355-6900, www.ametekusg.com

Amisco SpA, +39 02.99.00.181, www.amisco.it/en

Anchor Fluid Power, (513) 527-3525, www.anchorfluidpower.com

Anderson Fittings, (708) 535-9030, www.andersonfittings.com

Anderson Metals Corp., 1701 Southern Rd., Kansas City, MO 64120, (816) 471-2600, Fax: (816) 472-8700, info@andersonmetals.com, www.andersonmetals.com

Anver Corp., (978) 568-0221, www.anver.com

API Heat Transfer Inc., (716) 684-6700, www.apiheattransfer.com

Apple Rubber Products, (716) 684-6560, www.applerubber.com

Argo Hytos, (419) 353-6070, www.yourfsp.com

Aries Engineering Co. Inc., (734) 529-8855, www.hypercyl.com

Ark-Plas Products Inc., (501) 453-2343, www.ark-plas.com

Arrow Pneumatics, (708) 343-9595, www.arrowpneumatics.com/fluidpower

ASA Hydraulik of America, 160 Meister Ave. #20A,Branchburg, NJ 08876, (908) 541-1500, Fax:(908) 541-1550, sales_us@asahydraulik.com, www.asahydraulik.com

Ashcroft Inc., (203) 378-8281, www.ashcroft.com

ASL Technologies LLC, (219) 736-7177, www.aslfilter.com

ASM Sensors Inc., (630) 832-3202, www.asmsensors.com

Astyx Inc., (800) 620-2126, www.astyx.net

Atlas Cylinders, (847) 298-2400, www.atlascylinders.com

Atos spa, +39 0331 922078, www.atos.com

Attica Hydraulic Exchange, (810) 949-4240, www.ahx1.com

Ausco Products Inc., (616) 926-0842, www.auscoproducts.com

Automatic Valve Corp., (248) 474-6700, www.automaticvalve.com

AutomationDirect, 3505 Hutchinson Rd., Cumming, GA 30040, (770) 889-2858, Fax:(770) 889-7876, sales@automationdirect.com, www.automationdirect.com

AW Co., (262) 884-9800, www.awcompany.com

Axco Valve Co., (814) 665-8268

Axiomatic Technologies(905) 602-9270, www.axiomatic.com

2014 Manufacturers' Index continued, B-C

B & H Machine Inc., (330) 868-6425, www.bhcylinders.com

Bailey International Corp., (865) 588-6000, www.baileynet.com

Bal Seal Engineering Inc., (949) 460-2100, www.balseal.com

Balluff Inc., (859) 727-2200, www.balluff.com

Barksdale Inc., (323) 589-6181, www.barksdale.com

Barrington Automation, (815) 477-1400, www.barrington-atn.com

Beach Filter Products Inc., (717) 235-1136, www.beachfilters.com

Behringer Corp., (973) 948-0226, www.behringersystems.com

Beswick Engineering Co. Inc., (603) 433-1188, www.beswick.com

Bieri Hydraulik, (717) 767-3200, www.bierihydraulik.com

Bimba Mfg. Co., 708) 534-8544, www.bimba.com

Bimo SJ Seals, (250) 478-3176, www.bimo.com

Bonfiglioli North America Inc., (905) 738-4466, www.bnagear.com

Bobalee Hydraulics, (712) 845-4554, www.bobalee.com

Bondioli & Pavesi, (804) 550-2224, www.bypy.it

Bosch Rexroth Corp., Industrial Hydraulics, (610) 694-8300, www.boschrexroth-us.com

Bosch Rexroth Corp., Mobile Hydraulics, (864) 967-2777, www.boschrexroth-us.com

Bosch Rexroth Corp., Pneumatics Div., (859) 254-8031, www.boschrexroth-us.com/brp

BrakeQuip LLC, (865) 251 9193, www.brakequip.com

Brand Hydraulics Inc., 2332 S. 25th St., Omaha, NE 68105,(402) 344-4434, Fax: (402) 341-5419, www.brand-hyd.com

Brennan Industries Inc., 6701 Cochran Road, Solon, Ohio 44139, (440) 248-1880, Fax: (440) 248-7282, www.brennaninc.com

Brevini USA Inc., (847) 478-1000, www.breviniusa.com

Bridgestone Co. Inc., (847) 520-0202, www.bridgestone.net

BSF Inc., (937) 885-7824, www.bsfinc.net

Bucher Hydraulics, +49 7742 8520, www.bucherhydraulics.com

BVA Hydraulics, (816) 891-6390, www.bvahydraulics.com

C.matic srl, Via Gramsci 20, 20042, Albiate Milan, Italy, +39 0362 805246, Fax:+ 39 0362 805262, cmatic@cmatic.it, www.cmatic.it

C.W. Marsh Co., (231) 722-3781, www.cwmarsh.com

Cadsym, (613) 476-5537, www.cadsym.com

Cal-West Machining, (714) 637-4161, www.cal-westmachine.com

Calzoni Motors, (901) 369-5404, www.etshydro.com

Camozzi Pneumatics Inc., (972) 548-8885, www.camozzi-usa.com

Canfield Connector, (330) 758-8299, www.canfieldconnector.com

Canimex Hydraulique, (819) 477-1335, www.canimex.com

Caplugs LLC, (716) 876-9855, www.caplugs.com

Carlson Hydraulics, (316) 944-0040, www.carlsonhyd.com

Casappa Corp., (630) 761-0041, www.casappa.com

Cascade Precision, (503) 663-9506, www.cascadeprecision.com

CBF Srl, +39.0444.499.141, www.cbfhydraulic.com

CEJN Industrial Corp., (847) 263-7200, www.cejn.com

Celesco Inc., (818) 701-2750, www.celesco.com

Centa, 2570 Beverly Dr. #128., Aurora, IL 60502, (630) 236-3500, info@centacorp.com, www.centa.info

Checkfluid Inc., (519) 652-6373, www.checkfluid.com

Chevron USA, (800) 582-3835, www.chevronlubricants.com

Chicago Fittings Corp., (815) 334-8000, www.chicagofittings.com

Chicago Gasket Co., (773) 486-3060, www.chicagogasket.com

Christopher Tool & Mfg., (440) 248-8080, www.christophertool.com

Cinch Connectors, (630) 705-6000, www.cinch.com

Circle Seal Controls Inc., (909) 270-6200, www.circle-seal.com

Citgo Petroleum Corp., (918) 495-4746, www.citgo.com

CKD USA Corp., (847) 368-0539, www.ckdusa.com

Clinton Industries, (713) 523-5521, www.clintonindustries.com

Clippard Instrument Laboratory Inc., 7390 Colerain Ave., Cincinnati, OH 45239,  (513) 521-4261, Fax:(513) 521-4464, leads@clippard.com, www.clippard.com

Coilhose Pneumatics, (732) 390-8480, www.coilhose.com

Colder Products Co., (651) 645-0091, www.colder.com

Colonial Seal Co., (856) 432-0012, www.colonialseal.com

Comer Inc., (704) 588-8400, comerindustries.com

Continental Hydraulics, (952) 895-6400, www.continentalhydraulics.com

Control Line Equipment Inc., (216) 433-7766, www.control-line.com

Control Products Inc., (973) 887-9400, www.cpi-nj.com

ControlAir Inc.,(603) 886-9400, www.controlair.com

Coxreels, (480) 820-6396, www.coxreels.com

Cross Mfg. Inc., 100 James H. Cross Blvd., Lewis, KS 67552, (620) 324-5525, Fax:(620) 324-5737, info@crossmfg.com, www.crossmfg.com

Crouzet Corp., (972) 471-2565, www.crouzet-usa.com

CRS Service Inc., (248) 652-9940, www.crsservice.com

Cunningham Mfg., (206) 767-3713, www.cunninghamcylinders.com

Custom Control Sensors, (818) 341-4610, www.ccsdualsnap.com

Custom Cylinders, (847) 516-6468, www.customcylinders.com

Custom Sensors & Technologies, (805) 552-3599, www.cstsensors.com

Cy.Pag S.r.l., +39 0342 60 50 11, www.cypag.com

2014 Manufacturers' Index continued, D-E

DADCO Inc., (734) 207-1100, www.dadco.net

Daman Products Co. Inc., (574) 259-7841, www.daman.com

Danfoss, 2800 E. 13th St., Ames, IA 50010-8600, (515) 239-6000, powersolutions.danfoss.com

Datum-A-Industries Inc., (763) 479-1133, www.datum-manifolds.com

De-Sta-Co Industries, (248) 594-5600, www.destaco.com

Decker Engineering, (949) 582-3908, www.deckerairlogic.com

Deere & Co., Cylinder Group, (309) 765-7596, www.deere.com

DEL Hydraulics Inc., (716) 853-7996, www.delhydraulics.com

Delaware Mfg. Industries Corp., (716) 743-4360, www.dmic.com

Delta Computer Systems Inc., (360) 254-8688, www.deltamotion.com

Delta Power Co., (815) 397-6628, www.delta-power.com

Delta Q, 3755 Willingdon Ave., Burnaby, BC, Canada V5G 3H3, (604) 327-8244, Fax: (604) 327-8246, www.delta-q.com

Deltrol Fluid Products, Div. of Deltrol Corp.(708) 547-0500, www.deltrolfluid.com

Demac SrL, Via R. Murri.14 20013, Magenta MI, Italy, +39 02-9784488, fax: +39 02-97003509, info@demac.it, www.demac.it

Des-Case Corp., (615) 672-8800, www.descase.com

Deschner Corp., 3211 W. Harvard St., Santa Ana, CA 92704, (714) 557-1261, Fax:(714) 557-4762, info@deschner.com, www.deschner.com

Detroit Coil Co., (248) 398-5600, www.detroitcoil.com

Deublin Co., (847) 689-8600, www.deublin.com

Diamond Hydraulics Inc., (409) 986-3957, www.diamondhydraulics.com

Dichtomatik Americas, (952) 894-8400, www.dichtomatik.us

Differential Pressure Plus, 16 Carriage Hill Drive, Branford, CT 06405, (203) 481-2545, Fax: (203) 643-2152 www.differentialpressure.com

Dixon Brass, (630) 323-4442, www.americancouplings.com

Dixon Valve & Coupling Co., (410) 778-2000, www.dixonvalve.com

Doering Co., (320) 743-2276, www.doering.com

Dofasco-Copperweld, Mechanical Tubing Div., (419) 342-1200, www.arcelormittal.com/tubular

Donaldson Co. Inc., (952) 887-3131, www.donaldson.com

Douce-Hydro Inc., (586) 566-4725, www.doucehydro.com

Duff Norton, (704) 588-4610, www.duffnorton.com

Dura-Bar, (815) 338-7800, www.dura-bar.com

Dwyer Instruments Inc., (219) 879-8000, www.dwyer-inst.com

Dylix Corp., (716) 773-2985, www.dylixcorp.com

Dynamco, (706) 336-3430, www.dynamco.com

Dynamic Fluid Components Inc., (864) 638-5544, www.dynamicfc.com

Dynex/Rivett Inc., (262) 691-2222, www.dynexhydraulics.com

Dynisco Instruments, (508) 541-9400, www.dynisco.com

Eaton Hydraulics, (952) 937-9800, www.hydraulics.eaton.com

EDCO USA, (314) 349-8011, www.edcousa.net

Eldon James Corp., (970) 667-2728, www.eldonjames.com

Elesa USA Corp., (330) 405-1300, www.elesa.com

Elettrotec Usa Inc., (775) 313-0708, www.elettrotec.it

Elwood Corp., Fluid Power Group, (414) 764-7500, www.elwood.com

EMJ, (323) 567-1122, www.emjmetals.com

Emmegi Heat Exchangers Inc., (602) 438-7101, www.emmegiinc.com

Enduro Industries Inc., (573) 248-2084, www.chromerod.com

Energy Mfg. Co. Inc., (319) 465-3537, www.energymfg.com

Enerpac, an Actuant Co., (262) 781-6600, www.enerpac.com

Enertrols, (734) 595-4500, www.enertrols.com

Enfield Technologies, (203) 375-3100, www.enfieldtech.com

Enhanced Polymers, (248) 583-7767, www.mfpseals.com

Entertron Industries Inc., (716) 772-7216, www.entertron.com

EPCO Products Inc., (260) 747-8888, www.zeroleak.com

EPE Industrial Filters Inc.,(847) 381-0860, www.eppensteiner.de

Eredi Baitelli S.p.A., +39 030 77 67 811, www.eredibaitelli.it

Eskridge, (913) 782-1238, www.eskridgeinc.com

European Industrial Products, (901) 375-0011, www.eip.us.com

Europower Inc., (216) 447-0898, www.europowerinc.com

Everything Hydraulic LP, (972) 266-2700, www.newcylinders.com

Exair Corp., (513) 671-3322, www.exair.com

Exxon Mobil, (800).662-4525, www.mobilindustrial.com

2014 Manufacturers' Index continued, F-G

Fabco-Air Inc., (352) 373-3578, www.fabco-air.com

Fairchild Industrial Products Co., (336) 659-3400, www.fairchildproducts.com

Fairview Fittings, (716) 614-0320, www.fairviewfittings.com

Famic Technologies, (514) 748-8050, www.automationstudio.com

Faster Inc., 6560 Weatherfield Ct., Maumee, OH 43537, (800) 231-2501, info@fasterinc.com, www.fasterinc.com

FasTest, (651) 645-6266, www.fastestinc.com

FCP Filters, (717) 627-1550, www.fcp-filters.com

Ferry Inc., (716) 684-1703, www.hyd-kits.com                                   

Festo Corp., 395 Moreland Rd.., Hauppauge, NY 11788, (800) 993-3786, Fax:(800) 963-3786, customer.service@us.festo.com, www.festo.com/us

Filtration Products Corp., (763) 478-6921, www.filtrationproducts.com

Filtrec North America, (705) 256-6622, www.filtrec.net

Filtroil Inc., (434) 293-3100, www.filtroil.com

Finn-Power USA, (847) 885-3200, www.finnpower.com

FIPA Inc., (919) 244-1848, www.fipa.com

Firestone Industrial Products Co., (317) 818-8600, www.firestoneindustrial.com

Fisher Hydraulics, (712) 845-2634, www.fisherhydraulics.com

Fittings Unlimited Inc., (817) 861-2651, www.fittingsunlimited.com

Flairline, (248) 478-3330, www.flairline.com

Flanges Inc., (877) FLANGES, www.flangesinc.com

Flaretite Inc., 2284 Golden Pond Ct., Fenton, MI 48430, (810) 750-4140, Fax:(810) 629-4988, VitoA@Flaretite.com, www.flaretite.com

Flint Hydraulics Inc., (901) 794-4884, www.flinthyd.com

Flint Hydrostatics Inc., (901) 794-2462, www.flinthydrostatics.com

Flo-tech, (262) 639-6770, www.flotech.com

Flodar Fluid Power Fittings, (920) 682-6877, www.flodar.com

FloDraulic Controls Ltd., (905)702-9456, www.flodraulic.com

Flodyne Controls Inc., (908) 464-6200, www.flodynecontrols.com

Flow Ezy Filters Inc., (734) 665-8777, www.flowezyfilters.com

Flow Technology Inc., (480) 240-3400, www.ftimeters.com

Fluid Line Products Inc., (440) 946-9470, www.fluidline.com

Fluid Motion Sales, (972) 437-1333, www.fluidmotionsales.com

Fluid Power Associates Inc., (717) 840-7814, www.fluidpowerassociates.com

Fluid Power Inc., (215) 643-0350, www.fluidpowerinc.com

Fluid Technologies Inc., (405) 624-0400, www.fluidtechnologies.com

Fluidyne Fluid Power, 31915 Groesbeck Hwy., Fraser, MI 48026, (586) 296-7200, Fax: (888) 842.5377, sales@fluidynefp.com, www.fluidynefp.com

Fluidtechnik USA Inc., (610) 321-2407, www.fluidtechnikusa.com

FOR Spa, +39 0532 825211, www.forfittings.it

Force America, (952) 707-1300, www.forceamerica.com

Foster Hydraulics Inc., (502) 937-1666, www.fosterhyd.com

Foster Mfg. Co. Inc., 2324 W. Battlefield Rd., Springfield, MO 65807, (417) 881-6600, Fax: (417) 881-3645, foster@couplers.com, www.couplers.com

Freelin-Wade Co., (503) 434-5561, www.freelin-wade.com

Galland Henning Nopak Inc., (414) 645-6000, www.nopak.com

Garlock Sealing Technologies, (315) 597-4811, www.garlock.com

Garrison Mfg., 714-549-4880, www.garrisonmfg.com

Garrod Hydraulics Inc., (717) 767-6429, www.garrod.com

Gast Mfg. Corp., (616) 926-6171, www.gastmfg.com

Gates Corp., (303) 744-1911, www.gates.com

GEA PHE Systems USA, (717) 268-6200, www.geaphena.com

Gear Products Inc., (918) 234-3044, www.gearproducts.com

Geartek, (662) 286-2252, www.geartek.com

Gems Sensors, (860) 747-3000, www.gemssensors.com

Generant Co. Inc., (973) 838-6500, www.generant.com

Georgia Hydraulic Int’l., 678-355-2240, www.georgiahydraulics.com

Glassport Cylinder Works, (724) 483-1790, www.tristatehyd.com

Globe Air Motor, (905) 606 2324, www.globeairmotor.com

GP:50, (716) 773-9300, www.gp50.com

Graham Corp., (585) 343-2216, www.graham-mfg.com

Graham-White Mfg., (540) 387-5600, www.grahamwhite.com

Granite Fluid Power, (320) 564-2311, www.gfpmf.com

Granzow Inc., (704) 845-2300, www.granzow.com

Green Mfg. Inc., (419) 352-9484, www.wcnet.org/~gmi/

Greenco Corp., (813) 882-4400, www.greencocylinders.com

Greene, Tweed & Co., (215) 256-9521, www.gtweed.com

Greenerd Hydraulics, (603) 889-4101, www.greenerd.com

Grover Corp., (414) 384-9472, www.groverpr.com

GS-Hydro U.S. Inc., (281) 209-1000, www.gshydro.com

2014 Manufacturers' Index continued, H-J

Hader-Seitz Inc., (262) 641-8200, www.hader-seitz.com

Haldex Barnes Corp., (815) 398-4400, www.hbus.haldex.com

Hallite Seals Int’l., (248) 668 5200, www.hallite.com

Hanna Cylinders, (847) 990-7700, www.hannacylinders.com

Harman Corp., (248) 651-4477, www.harmancorp.com

Hartmann Controls Inc., (262) 367-4299, www.hartmanncontrols.com

Harvard Corp., (608) 882-6330, www.harvardcorp.com

Haskel International Inc., 100 East Graham Place, Burbank, CA 91502, (818) 843-4000, Fax: (818) 556-2549, sales@haskel.com, www.haskel.com

Hatec International Inc., (713) 466-6673, www.hatecinc.com

Hauhinco, (724) 789-7050, www.hauhinco.com

HAWE Hydraulics, 9009-K Perimeter Woods Dr., Charlotte, NC 28216, (704) 509-1599, Fax: (704) 509-6302, info@haweusa.com, www.hawehydraulics.com

Hayden Industrial Products, (951) 736-2600, www.haydenindustrial.com

HDM Hydraulics, (716) 694-8004, www.hdmhydraulics.com

HECO Inc., (916) 372-5411, www.heco-inc.com

Hedland, (262) 639-6770, www.hedland.com

Heinrichs USA LLC, 2595 Arbor Tech Dr., Hebron, KY 41048, (859) 371-4999, Fax:(859) 371-4899, mail@heinrichs-usa.com, www.heinrichs-usa.com

Helac Corp., (360) 825-1601, www.helac.com

Henderson Engineering Co. Inc., (815) 786-9471, www.saharahenderson.com

Hercules Sealing Products, 1016 North Belcher Rd., Clearwater, FL 33765, (727) 796-1300, Fax: (727) 797-8849, sales@herculesusa.com, www.herculesus.com

Heypac Inc., (248) 652-3500, www.heypac.com

Hi-Tech Controls Inc., (303) 680-5159, www.hitechcontrols.com

Hidrodinamica Inc., (847) 357-1440, www.hidrodinamica.net

High Country Tek, (530) 265-3236, www.highcountrytek.com

HL Hydraulic, 814-677-4086, www.hlhydraulic.com

Holmbury, (440) 578-1070, www.holmburyusa.com

Holmes Automation Components Inc., (336) 764-8413

Honeywell, (815) 235-6847, sensing.honeywell.com

Honor Pumps, (713) 984-9727, www.honorpumps.com

Horton Mfg., (918) 836.3971, www.hortonmfgusa.com

Houghton Int’l. Inc., (610) 666-4000, www.houghtonintl.com

HPS Inc., (856) 224-1120, www.hpsseals.com

Humphrey Products, (616) 381-5500, www.humphrey-products.com/

Hunger Hydraulics CC Ltd., 63 Dixie Hwy., Rossford, OH 43460, (419) 666-4510, Fax:(419) 666-9834, hungercc@glasscity.net, www.hunger-group.com

HUSCO International, (262) 513-4200, www.huscointl.com

Hy-Pro Filtration, (317)849-3535 , hyprofiltration.com

Hyco International Inc., (256) 931-2205, www.hyco.net

HYDAC Technology Corp., (610) 266-0100, www.hydacusa.com

Hyde Tools, Industrial Blade Solutions Div., 54 Eastford Rd., Southbridge, MA 01550, (508) 764-4344, Fax:(508) 764-8172, sales@hydeblades.com, www.hydeblades.com

Hydra-Power Systems Inc., (503) 777-3361, www.hpsx.com

Hydra-Zorb Co., (248) 373-5151, www.hydra-zorb.com

HydraCheck, (801) 908-5717, www.hydracheck.com

HydraForce, (847) 793-2300, www.hydraforce.com

Hydranamics, Inc., (419) 468-3530, www.hydranamics.com

Hydratech Industries, (251) 947-5300, www.hydratech-industries.com

Hydraulic Parts Source, (586) 463-3166, www.hydparts.com

Hydraulic Power Systems, (810) 547-0150, www.hpscorp.com

Hydraulic Specialty Co., (763) 571-3072, www.hydraulicspecialty.com

Hydraulic Technologies, (419) 462-2300, www.hydraulictechnologies.com

Hydraulics Int’l. Inc., (818) 407-3420, www.flowmetrics.com

Hydraulics Inc., 2935 St. Louis Ave., Ft. Worth, TX 76110, (817) 923-1965, Fax:(817) 927-8002, sales@hydraulicsinc.com, www.hydraulicsinc.com

Hydreco, (704) 295-7575, www.hydreco.com

Hydro Leduc LP, (281)679-9654, www.hydroleducusa.com

Hydro Safe Oil Div. Inc., (517) 669-1212, www.hydrosafe.com

Hydro Tube Corp., (216) 774-1022, www.hydrotube.com

Hydro-Craft Inc., (248) 652-8100, www.hydro-craft.com

Hydro-Gear, (217) 728-2581, www.hydro-gear.com

Hydro-Line Inc., (815) 654-9050, www.hydro-line.com

Hydro/Power LLC, (205) 520-1220, www.hydropower1.com

Hydrolico International, (450) 628-6644, www.hydrolico.com

Hydronic Corp., (248) 477-2288, www.hydroniccorp.com

Hydroperfect Int’l. Inc., (905) 791-3388, www.hpicanada.com

Hypac Inc., (606) 849-2477, www.hypachydraulics.com

Hyvair Corp., (713) 937-3428, www.hyvair.com

IC Fluid Power Inc., 63 Dixie Hwy., Rossford, OH 43460, (419) 661-8811, Fax:(419) 661-8844, us@icfluid.com, www.icfluid.com

IFM Efector Inc., (610) 524-2000, www.ifm.com/us

igus Inc., (401) 438-2200, www.igus.com

IMD/LSI Hydraulic Products, (714) 847-3197, www.Industrial Hard Chrome Ltd., (630) 208-7000

Industrial Nut Corp., (419) 625-8543, www.industrialnut.com

Industrial Servo Hydraulics Inc., (586) 296-0960, www.indservo.com

Industrial Specialties Mfg. Inc., (303) 781-8486, www.industrialspec.com

Innotek Corp., (763) 493-2810, www.innotek-ep.com

Interface Devices Inc., (203) 878-4648, www.interfacedevices.com

International Fluid Power of America, (888) 220-1414, www.intlfpa.com

iQ Valves, (321) 729-9634, www.iqvalves.com

ISOPur Fluid Technologies, (860) 571-8590, www.isopurfluid.com

ITT Neo-Dyn, (805) 295-4104, www.neodyn.com

ITT Standard, (716) 897-2800, www.ittstandard.com

J.R. Merritt Controls Inc., (203) 381-0100, www.jrmerritt.com

J. W. Winco, 2815 S. Calhoun Road., New Berlin, WI 53151, (800) 877-8351, Fax: (800) 472-0670, www.jwwinco.com

Jarp Industries Inc., (715) 359-4241, www.jarpind.com

Jefferson Solenoid Valves USA, (305) 249-8120, www.jeffersonvalves.com

JET Industries Inc., (734) 641-0900, www.jetmuffler.com

JIT Cylinders, (256) 751-2548, www.jitcylinders.com

JLM Systems Ltd., (604) 521-3248, www.oilmiser.com

JWF Technologies, 6820 Fairfield Business Dr., Fairfield,OH 45014, (513) 769-9611, Fax: (513) 769-0109, info@jwftechnologies.com, www. jwftechnologies.com

Jun-Air USA Inc., (847) 215-9444, www.jun-air.com

2014 Manufacturers' Index continued, K-M

Kaeser Compressors Inc., (540) 898-5500, www.kaeser.com

Kawasaki Precision Machinery of America, (616) 949-6500, www.kawasakipmd.com

Kay Pneumatics, (417) 781-2242, www.kaypneumatics.com

Kebby Industries Inc., (815) 963-1466, www.kebbyindustries.com

Keller America Inc., 813 Diligence Dr., Ste. 120, Newport News, VA 23606, (757) 596-6680, Fax:(757) 596-6659, sales@kelleramerica.com, www.kelleramerica.com

Kentak Products Co., (330) 532-6211, www.kentak.com

Kepner Products Co., 995 N. Ellsworth Ave., Villa Park, IL 60181, (630) 279-1550, Fax:(630) 279-9669, kepner@kepner.com, www.kepner.com

Kleentek, (513) 891-0400, www.kleentek.com

Kobold Instruments Inc., (412) 788-2830, www.kobold.com

Kocsis Technologies, (708) 597-4177, www.kocsistech.com

KTR Corp., (219) 872-9100, www.ktrcorp.com

Kuhnke Automation Inc., (973) 633-0690, www.kuhnkeusa.com

Kuriyama of America Inc., 360 E. State Parkway, Schaumburg, IL 60173-5335, (847) 755-0360, Fax:(847) 885-0996, sales@kuriyama.com, www.kuriyama.com

Kurt Hydraulics, 302 Jeffers Ave., Lyman, NE 69352, (308) 787-1211, Fax:(308) 787-1281, kurthyd@aol.com, www.kurthydraulics.com

KYB America LLC, (630) 620-5555, www.kyb.com

L&L Fittings Mfg., (219) 747-9200, www.llfittings.com

La-Man Corp., (386) 304-0411, www.laman.com

Lake Monitors Inc., div., Total Automated Solutions Inc., (414) 671-3577, www.lakemonitors.com

Lee Co., The, 2 Pettipaug Rd., Westbrook, CT 06498, (860) 399-6281, Fax:(860) 399-2270, inquiry@theleeco.com, www.theleeco.com

Legris Inc., (480) 830-0216, www.legris.com

Lehigh Fluid Power Inc., (609) 397-3487, www.lehighfluidpower.com

Lenz, (937) 277-9364, www.lenzinc.com

Lexair Inc., (859) 255-5001, www.lexairinc.com

Lifco Hydraulics, (905) 641-0033, www.lifcohydraulics.com

Ligon Hydraulic Cylinder Group, (641) 456-4411 www.hydrauliccylindergroup.com

Lillbacka USA Inc., 1629 Prime Ct., Ste 400., Orlando, FL 32809, (847) 301-1300, Fax: (847) 301-2562, sales@lillbackausa.com, www.lillbackausa.com

Linde Hydraulics Corp., (216) 533-2091, www.lindeamerica.com

Logic Hydraulic Controls, (910) 791-9293, www.logichyd.com

Lone Star Steel Co., (972) 770-6405, www.lonestarsteel.com

Lovejoy Inc., (630) 852-0500, www.lovejoy-inc.com

Lube Devices Inc., (920) 682-6877, www.lubedevices.com

Lubriquip Inc., (216) 581-2000, www.lubriquip.com

Lumberg Inc., (804) 379-2010, www.lumbergusa.com

Lynch Fluid Controls Inc., (905) 363-2400, www.lynch.ca

M&W Mfg Co., Inc., (319) 362-8930, www.mandwmfg.com

Mac Valves Inc., (248) 624-7700, www.macvalves.com

Mack Corp., (928) 526-1120, www.mackcorp.com

MacMillin Hydraulic Engineering Corp., (847) 676-2910, www.macmhydraulic.com

MacTaggart, Scott & Co. Ltd., (508) 238-9889, www.mactag.com

Magnaloy Coupling Co., (989) 356-2186, www.magnaloy.com

Magnet-Schultz of America, (630) 789-0608

Mahle Industrial Filtration USA Inc., www.us.mahle.com

Mailhot Industries, (514) 839-3663, www.mailhotindustries.com

Main Mfg. Products Inc., 3181 Tri Park, Grand Blanc, MI 48439, (810) 953-1380, Fax:(810) 953-1385, info@mainmfg.com, www.mainmfg.com

Manastrip Corp., (518) 399-0889, www.thomasregister.com/manastrip

Manuli Hydraulics Americas Inc., (724) 778-3380, www.manuli-hydraulics.com

Marken Mfg. Co., (763) 577-0111, www.markenmfg.com

Marmon/Keystone Corp., (724) 283-3000, www.marmonkeystone.com

Marsh Bellofram, (304) 387-1200, www.marshbellofram.com

Martin Fluid Power, (248) 585-8170, www.mfpseals.com

Marzocchi Pumps USA, (847) 923-9910, www.marzocchipumpsusa.com

Master Pneumatic Inc., 6701 Eighteen Mile Rd., Sterling Heights, MI 48314, (586) 254-1000, Fax: (586) 254-6055, mp@masterpneumatic.com, www.masterpneumatic.com

Max Machinery Inc., (707) 433-7281, www.maxmachinery.com

Maxpro Technologies, (814) 474-9191, www.maxprotech.com

Mazzer Industries, (585) 247-0311, www.mazzerplastics.com

Mead Fluid Dynamics, (773) 685-6800, www.mead-usa.com

Measurement Specialties, (757) 766-1500, www.msiusa.com

Med-Kas Hydraulics Inc., (248) 585-3220, www.med-kas.com

Metal-Matic Inc., (800) 328-5494, www.metal-matic.com

Metaris Inc., (416) 638-6000, www.metaris.com

MICO Inc., (507) 625-6426, www.mico.com

Micro Pneumatic Logic, (954) 788-3611, www.pressureswitch.com

Micromatic LLC, (260) 589-2136, www.micromaticllc.com

Mid-America Fittings (913) 962-7277, www.midamericafittings.com

Midland Metal Mfg, (800) 821-5725, www.midlandmetal.com

Midwest Brake, (586) 775-3000, www.midwestbrake.com

Mikron Rubber Products Corp., (323) 245-1251

Milwaukee Cylinder, (414) 769-9700, www.milwaukeecylinder.com

Mindman Pneumatics, No. 106, Sec.3, Chende Rd., Datong District, Taipei City 103, Taiwan, +886 2-25914100, Fax: +886 2-25957633, www.mindman.com.tw/en

Minnesota Rubber, (952) 927-1400, www.mnrubber.com

MKS Instruments Inc., (978) 284-4000, www.mksinst.com

Monarch Hydraulics Inc., (616) 458-1306, www.monarchhyd.com

Monarch Industries, (204) 786-7921, www.monarchindustries.com

Monnier Inc., (810) 794-4935, www.monnier.com

Moog Flo-Tork, (330) 682-0010, www.flo-tork.moog.com

Moog Inc., (716) 652-2000, www.moog.com/industrial

Motion Controls LLC, (262) 673-9255, www.motioncontrolsllc.com

Motion Industries, (205) 956-1122, www.motionindustries.com

MP Filtri USA, Inc., 2055 Quaker Pointe Dr., Quakertown, PA 18951, (215) 529-1300, Fax:(215) 529-1902, sales@mpfiltriusa.com, www.mpfiltriusa.com

MRF Machine and Hydraulics Inc., (330) 673-0135, www.mrfmachine.com

MSC.Software, (EASY5), (425) 644-3920, www.mscsoftware.com

MSO Seals, 4702 Steffani Lane,  Houston, TX 77041, (713) 468-7500, Fax:713-468-3663, msohq@sbcglobal.net, www.123seal.com

MTS Systems Corp., Sensors Div., (919) 677-0100, www.mtssensors.com

Multicyl Inc., (905) 951-0670, www.multicyl.com

Muncie Power Products Inc., P.O. Box 548, Muncie, IN 47308-0548, (765) 284-7721, Fax:(765) 284-6991, info@munciepower.com, www.munciepower.com

Murrelektronik Inc., (215) 230-4470, www.murrinc.com

2014 Manufacturers' Index continued, N-O

Nachi America Inc., Hydraulics Div., (800) 622-4410, www.nachihydraulics.com

Nason Co., (864) 638-9521, www.nasonptc.com

NC Servo Technology, (734) 326-6666, www.ncservo.com

NewAge Industries Inc., (215) 526-2300, www.newageindustries.com

Niagara Plastics Co., (814) 868-3671, www.niagaraplastics.com

Nike Hydraulics Inc., (815) 385-7777, www.nikehydraulics.com

Nimco Controls Inc., (262) 884-0950, www.nimco-controls.com

NitroSteel, (262) 947-0441, www.macsteel.com

Norgren Inc., (303) 794- 2611, www.norgren.com/us

Norman Filter Co., (708) 233-5521, www.normanfilters.com

Norstat Inc., (973) 586-2500, www.norstat.com

North American Hydraulics LLC, 11549 Sunbelt Ct., Baton Rouge, LA 70809 , (225) 751-0500,Fax:(225) 751-0610, info@nahi.com, www.nahi.com

Northlake Steel Corp., (330) 220-7717, www.northlakesteel.com

Northman Fluid Power, (630) 588-8488, www.northmanfp.com

Norton Performance Plastics, (847) 439-7400

Noshok Inc., (440) 243-0888, www.noshok.com

Novotechnik U.S. Inc., (508) 485-2244, www.novotechnik.com

NRP-Jones, (219) 362-9908, www.nrpjones.com

Nucor Cold Finish, (402) 644-8600, www.nucor.com

Numatics Inc., Cylinder Div., (615) 771-1200, www.numatics.com

Numatics Inc., (248) 887-4111, www.numatics.com

Nutron Motor Co., (508) 717-5441, www.nutronmotors.com

Nycoil Co., (336) 495-0004, www.nycoil.com

O’Keefe Controls Co., (203) 261-6711, www.okcc.com

OEM Controls Inc., (203) 929-8431, www.oemcontrols.com

Oetiker Inc., (989) 635-3621, www.oetiker.com

Ogden Hydraulics, (419) 877-5388, www.ogdenhydraulics.com

Ogura Industrial Corp., (732) 271-7352, www.ogura-clutch.com

Oil Control North America, (847) 719-2950, www.oilcontrol.com

Oil-Rite Corp., (920) 682-6173, www.oilrite.com

Oilgear Co., (414) 327-1700, www.oilgear.com

OilPure Technologies Inc., (913) 906-0400, www.oilpure.com

Olmsted Products Co., (231) 929-1660, www.olmstedproducts.com

Omega Engineering Inc., (203) 359-1660, www.omega.com

Omega One Fittings Inc., (216) 663-8424, www.omegaone.net

OMT SpA, +39 0363860311, www.omtfiltri.com

OP Srl, +39 030-3580401, www.op-srl.it

Operating and Maintenance Specialties, (704) 523-4031, www.raysnubber.com

Orange Research Inc., (203) 877-5657, www.orangeresearch.com

Ortman Fluid Power, (217)277-0321, www.ortmanfluidpower.com

2014 Manufacturers' Index continued, P-Q

P-Q Controls Inc., (860) 583-6994, www.p-qcontrols.com                                   

PAC Servos Inc., (813) 728-5617, www.pacservos.com

PacSeal Hydraulics, (714) 529-9495, www.pacsealhydraulics.com

Pall Corp., (516) 484-3600, www.pall.com

Pamark Manifolds, (616) 456-6043, www.pamarkmanifolds.com

Parker Hannifin Corp., Accumulator & Cooler Div., (815) 636-4100, www.parker.com/accumulator

Parker Hannifin Corp., Actuator Div., (330) 336-3511, www.parker.com/actuator

Parker Hannifin Corp., Cylinder Div., (847) 298-2400, www.parker.com/cylinder

Parker Hannifin Corp., Engineered Polymer Systems Div., (801) 973-4019, www.parker.com/eps

Parker Hannifin Corp., Finite Airtek Filtration Div., (716) 686-6400, www.parker.com/faf

Parker Hannifin Corp., Filtration and Separation Div., (248) 628-6400, www.parker.com/finitefilter

Parker Hannifin Corp., Fluid Control Div., (860) 827-2300, www.parker.com/fcd

Parker Hannifin Corp., Gear Pump Div., (330) 746-8011, www.parker.com/gearpump

Parker Hannifin Corp., Hiross Zander Div., (678) 686-6400, www.zanderusa.com

Parker Hannifin Corp., Hose Products Div., (440) 943-5700, www.parkerhose.com

Parker Hannifin Corp., Hydraulic Filter Div., (419) 644-4311, www.parker.com/hydraulicfilter

Parker Hannifin Corp., Hydraulic Pump Div., (937) 644-4435, www.parker.com/hydraulicpump

Parker Hannifin Corp., Hydraulic Pump/Motor Div., (423) 639-8151, www.parker.com/pumpmotor

Parker Hannifin Corp., Hydraulic Valve Div., (440) 366-5200, www.parker.com/hydraulicvalve

Parker Hannifin Corp., Industrial Hose Products Div., (440) 268-2120, www.parker.com/indhose

Parker Hannifin Corp., Mobile Cylinder Div., (330) 480-8431, www.parker.com/mobilecylinder

Parker Hannifin Corp., Parflex Div., (330) 296-2871, www.parker.com/parflex

Parker Hannifin Corp., Pneumatic Div., (269) 629-5000, www.parker.com/pneumatics

Parker Hannifin Corp., Quick Coupling Div., (763) 544-7781, www.parker.com/quickcouplings

Parker Hannifin Corp., Tube Fittings Div., (614) 279-7070, www.parker.com/tfd

Patriot Sensors & Controls Corp., (805) 581-3985, www.xducers.com

PCB Piezotronics Inc., (716) 684-0001, www.pcb.com

Peninsular Cylinder Co., 27650 Groesbeck Hwy., Roseville, MI 48066-2759, (586) 775-7211, Fax:(586) 775-4545, sales@peninsularcylinders.com, www.peninsularcylinders.com

Penny + Giles Controls, (626) 480 2150, www.pennyandgiles.com

Pepperl + Fuchs Inc., (330) 425-3555, www.pepperl-fuchs.us

Permco Inc., (330) 626.2801, www.permco.com

Peter Paul Electronics Co., (860) 229-4884, www.peterpaul.com

Petro-Canada, (888) 284-4572, www.petro-canada.ca

PHD Inc., 9009 Clubridge Dr., Fort Wayne, IN 46809, (260) 747-6151, Fax: (260) 479-2312, phdifo@phdinc.com, www.phdinc.com

PIAB Vacuum Products, (781) 337-7309, www.piab.com

Pioneer Air Systems Inc., (423) 346-6693, www.pioneerair.com

Piranha Hose Products, (231) 779-4390, www.piranhahose.com

Pirtek, (321) 504-4422, www.pirtekusa.com

Pisco USA Inc., (630) 521-9220, www.pisco.com

Plymouth Tube Co., (630) 393-3550, www.plymouth.com

Pneucon, (209) 772-9555, www.pneucon.com

Pneumadyne Inc., (763) 559-0177, www.pneumadyne.com

Pneumatech LLC, (262) 658-4300, www.pneumatech.com

Pneumatic Cylinders & Couplers Inc., (815) 639-1000, www.pneumaticcylinders.net

Poclain Hydraulics, (262) 321-0676, www.poclain-hydraulics.com

Polyconn, (763) 559-0388, www.polyconn.com

Porous Media, (651) 653-2000, www.porous.com

Positech Corp., (712) 841-4548, www.positech-solutions.com

Powertrack Int’l Inc., (412) 787-4444, www.powertrackhose.com

Precise Hard Chrome, (817) 756-6879, www.precisechrome.com

Precision Fittings Inc., (440) 647-4143, www.precisionfittings.com

Precision Pneumatics, (631) 332-8107, precision-pneumatics.com

Preferred Products Design Inc., (203) 877-4399, www.preferredproductsdesign.com

Prince Mfg. Corp., 612 N Derby Ln., North Sioux City, SD 57049,  (605) 235-1220, Fax: (712) 233-2181, prince@princehyd.com, www.princehyd.com

Proportion-Air Inc., (317) 335-2602, www.proportionair.com

PTI Technologies, (805) 604-3700, www.ptitechnologies.com

Pulsco, (949) 261-1717, www.pulsco.com

Puregas LLC, (303) 427-3700, www.puregas.com

Purolator Facet Inc., (336) 668-4444, www.purolator-facet.com

PWM Controls Inc., (905) 542-1245, www.pwmcontrols.com

Quaker Chemical, (610) 832-4000, www.quintolubric.com

Quality Filtration, (615) 833-2400, www.qualityfiltration.com

Quick Coupling Technologies, 5101 Naiman Pkwy., Solon, OH 44139, (888) 282-1122, Fax:(440) 349-0324, sales@qctcouplings.com, www.qctcouplings.com

2014 Manufacturers' Index continued, R-T

Ram Industries Inc., (306) 786-2677, www.ramindustries.com

RB Royal Industries Inc., (920) 921-1550, www.rbroyal.com

Reason Technology Co. Ltd., +86 25 5278 8160, www.reasonmaterials.com

Reel-O-Matic, (405) 672-0000, www.reelomatic.com

Responsible Fluid Power, (605) 368-2300, www.responsiblefluidpower.com

Robitech Inc., (978) 657-6143, www.robitech.com

Rockford Linear Actuation Inc., (815) 986-4400, www.rockfordlinear.com

Ross Controls, (248) 764-1800, www.rosscontrols.com

Rota Engineering Ltd., Wellington St., Bury, Manchester, BL8 2BD, United Kingdom, (972) 359-1041, info@rota-eng.com, www.rota-eng.com

Rota-Cyl Corp., (610) 845-8001, www.rotacyl.com

Rotary Power Inc., (605) 361-5155, www.rotarypower.com

Rotomation Inc., (386) 677-6377, www.rotomation.com

Rotor Clip Co. Inc., (732) 469-7333, www.rotorclip.com

Royal Lubricants Co. Inc., (201) 887-7410, www.royallube.com

RR USA Inc., (610) 497-0154, www.rrusainc.com

RYCO Hydraulics, 1616 Greens Rd., Houston, TX 77032, (281) 821-4100, Fax:(281) 821-4300, sales@ryco.us, www.ryco.com.au

S. Himmelstein & Co., (847) 843-3300, www.himmelstein.com

Safeplast NA Co. Ltd., (519) 839-5866, www.safeplast.com

SafeWay Hydraulics Inc., (952) 466-6220, www.safewayhyd.com

SAI Hydraulics, +39 059 420111, www.saispa.com

Sandvik Materials Technology, SE-811 81 Sandviken., Sweden, +46 26 260000, Fax: +46 26 251710, www.smt.sandvik.com

SC Hydraulic Engineering Corp.,  1130 Columbia St., Brea, CA 92821, (714) 257-4800, Fax: (714) 257-4810, www.schydraulic.com

Scenery Hydraulic, Inc., 1939 S. Lake Place, Ontario, CA 91761, (909) 930-9586, Fax: (909) 354-3181, sales@sceneryhydraulic.com, www.sceneryhydraulic.com

Schmalz Inc., (919) 713-0880, www.schmalz.com

Schroeder Industries, (412) 771-4810, www.schroederindustries.com

Schunk Inc., (919) 572-2705, www.schunk.com

Scot Industries Inc., (414) 642-4600, www.scotindustries.com

Scott Rotary Seals, (716) 376-0708, www.scottrotaryseals.com

Seal Science, (714) 253-3130, www.sealscience.com

Selling Precision, (973) 728-1214, www.sellingprecision.com

Senior Aerospace, (781) 784-1400, www.metalbellows.com

Senior Flexonics Inc., Specialized Products Div., (630) 837-1811, www.flexonics.com

Sensor Products, (973) 884-1755, www.sensorprod.com

Separation Technologies, (615) 366-9787, www.fleetguard.com

Servo Kinetics Inc., (734) 996-4996, www.servokinetics.com

Setra Systems Inc., (978) 263-1400, www.setra.com

Sheffer Corp., (513) 489-9770, www.sheffercorp.com

Shell Lubricants, (800) 237-8645, www.shell.us

Sherex Industries Ltd., (716) 875-0176, www.sherex.com

Sierra Hydraulics & Machine, (707) 485-8850, www.sierrahyde.com

Sigma-Netics Inc., (201) 227-6372, www.sigma-netics.com

Simrit, Div. Freudenberg-NOK, (866) 274 6748, www.simritna.com

Smalley Steel Ring Co., 555 Oakwood Rd., Lake Zurich, IL 60047, (847) 719-5900, Fax:(847) 719-5999, info@smalley.com, www.smalley.com

SMC Pneumatics Inc., (317) 899-4440, www.smcusa.com

SOR Inc., (913) 888-2630, www.sorinc.com

Source Fluid Power Inc., (952) 368-3866, www.sourcefp.com

South Bend Controls, (574) 234-3157, www.sbcontrols.com

Southern Hydraulic Cylinder Inc., (423) 744-8988, www.southhydcyl.com

Spartan Scientific Inc., (330) 758-8446, www.spartanscientific.com

Specialized Fluid Systems, (800) 723-1674, www.hydraulic-manifolds.com

Specialty Tank & Reservoir, (920) 898-4221, www.spec-tank-res.com

Spectronics Corp., (516) 333-4840, www.spectroline.com

Spez-Tech, (905) 828-5579, www.speztech.com

Spir Star Inc., (713) 856-8989, www.spirstar.com

Sprague Products, (440) 838-7690, www.cwfc.com

SPX Hydraulics, (815) 874-5556, www.spxhydraulictech.com

SSP Fittings Corp., (330) 425-4250, www.sspfittings.com

Starcyl Cylinder USA Corp., (450) 967-1211,  www.starcyl.com

Stauff Corp., (201) 444-7800, www.stauffusa.com

Steel Supply Co., (847) 255-2460, www.steelsupply.com

Stellar Technology Inc., (716) 875-0279, www.stellartech.com

StockCap, (636)282-6800, www.stockcap.com

Stucchi Inc., (847) 956-9720, www.stucchiusa.com

Suco Technologies Inc., 6560 W. Rogers Cir. #22, Boca Raton, FL 33487, (800)-473-7313, Fax: 561-989-8816, info@suco-tech.com, www.suco-tech.com

Sun Hydraulics Corp., (941) 362-1200, www.sunhydraulics.com

Sunfab North America, (908) 534-1463, www.sunfabnorthamerica.com

Super Swivels, 7917 Beech St. NE, Minneapolis, MN 55432-1762, (763) 784-5531, Fax: 763-784-7423, sales@superswivels.com, www.superswivels.com

Swagelok Co., 440-248-4600, www.swagelok.com

Taiyo America Inc., (630) 691-8811, www.airpro-taiyo.com

Techno-Sommer, (516) 328-3970, www.techno-sommer.com

Terrell Mfg. Inc., (440) 238-5445, www.terrellmfg.com

Tescom Corp., Industrial Controls Div., (612) 441-6330, www.tescom.com

Texas Hydraulics, (254) 778-4701, www.texashyd.com

Texas Instruments, Inc., (508) 236-3929, www.tisensors.com

The IFH Group, (815) 626-1018, www.ifhgroup.com

Thermal Dynamics Int’l, (909) 390-3944, www.tdi-corp.com

Thermal Transfer Products, 5215 21st St., Racine, WI 53406-5096, (262) 554-8330, Fax: (262) 554-8536, ttpsales@thermasys.com, www.thermasys.com

Thistle Hydraulics Electronics Ltd., (905) 820-8937, www.thistlehydraulics.com

Thomas-Magnete USA, (262) 781-2900, www.thomas-magnete.com

Tobul Accumulator Inc., 186 Accumulator St., Bamberg, SC 29003, (803) 245-5111, Fax:(803) 245-2636, tobulmail@tobul.com, www.tobul.com

Tolomatic Inc., (763) 478-8000, www.tolomatic.com

Tomco Products, (440) 358-1000, www.tomcoquickcouplers.com

Tompkins Industries Inc., 1912 E 123rd St., Olathe, KS 66061, (800) 255-1008, Fax:(800) 959-3333, sales@tompkinsind.com, www.tompkinsind.com

Tonson Inc., (334) 702-8451, www.tonsoninc.com

Tower Oil & Technology Co., (773) 927-6161, www.toweroil.com

Tox Pressotechnik LLC, (630) 393-0300, www.tox-us.com

Tranter PHE Inc., (940) 723-7125, www.tranter.com

TRD Mfg. Inc., (815) 654-7775, www.trdmfg.com

Trelleborg Sealing Solutions, (260) 749-9631, www.tss.trelleborg.com/us

Trent Tube, (262) 642-7321, www.trent-tube.com

Trerice H. O. Co., (248) 399-8000, www.trerice.com

Triple R America Co. Ltd., (416) 413-9202, www.triple-rrr.com

Tube-Mac Industries Ltd., 420 Halstead Blvd., Zelienople, PA 16063, (905) 643-8823, fax: (724)473-0830, infousa@tube-mac.com, www.tube-mac.com

Turck Inc., (612) 553-7300, www.turck.com

Turn-Act Inc., (502) 263-7000, www.turn-act.com

Turolla OpenCircuitGear, (800) 239-6677, www.turollaocg.com

Twin Tower Engineering, (303) 465-3063, www.airdryers.com

2014 Manufacturers' Index continued, U-Z

Ultra Clean Technologies Corp., 746 Shiloh Pike, Bridgeton, NJ 08302, (856) 451-2176, Fax:(856) 453-4975, sales@ultracleantech.com, www.ultracleantechnologies.com

Ultrafilter Inc., (770) 448-3363, www.ultrafilter.com

Ultramation Inc., (817) 772-4860, www.ultramation.com

Uniflex of America Ltd., (847) 519-1100,  www.uniflex.de

Unisource Mfg., (503) 281-4673, www.unisource-mfg.com

United Electric Controls, (617) 926-1000, www.ueonline.com

Universal Flow Monitors, (248) 542-9635, www.flowmeters.com

Universal Hydraulics Int’l., (330) 405-1800, www.uhiltd.com

Utex Industries Inc., (713) 467-1000, www.utexind.com                                   

V & P Hydraulic Products, (740) 548-5181, www.vphyd.com                                   

Vaccon Co. Inc., (508) 359-7200, www.vaccon.com

Value Plastics Inc., (970) 267-5200, www.valueplastics.com

Van Air Systems Inc., (814) 774-2631, www.vanairsystems.com

Velcon Filters Inc., (719) 531-5855, www.velcon.com

Veljan Hydrair Private Ltd., A-18 & 19, Apie, Balanagar, Hyderabad, IN 500037, India, +91-40-23772794, Fax:+91-40-23773963, info@veljan.com, www.veljan.com

Vermatic Products Inc., (262) 513-9384, www.vermatic.com

Versa Products Co. Inc., (201) 843-2400, www.versa-valves.com

Vescor Corp., (847) 742-7270, www.vescor.com

Vest Inc., (248) 641-8088, www.vestusa.com

Viatran Corp., (716) 773-1700, www.viatran.com

Victory Controls LLC, (860) 589-4230, www.victorycontrols.com

Viking Pump, (319) 266-1741, www.vikingpump.com

Voith Turbo Inc., (717) 767-3200, www.usa.voithturbo.com

Von Ruden Mfg. Inc., (763) 682-3122, www.vonruden.com

Vonberg Valve Inc., (847) 259-3800, www.vonberg.com

Voss Fluid GmbH, (260) 969-4423, www.vossusa.com

W.C. Branham Inc., (715) 426-2000, www.wcbranhaminc.com

Wandfluh AG., 909 High St., Mundelein, IL 60060, (847) 566-5700, sales@wandfluh.com, www.wandfluh-us.com

Warren Electric Corp., (401) 245-3700, www.warrenelectriccorp.com

Webco Industries, (918) 245-2211, www.webcotube.com

Webster Instruments, 1290 E. Waterford Ave., Milwaukee, WI 53235, (414) 769-6400, Fax:(414) 769-6591, sales@webster-inst.com, www.webster-inst.com

Western Filter Corp., (615) 984-4418, www.w-t-f-llc.com

White Drive Products, (270) 885-1110, www.whitehydraulics.com

White Oak Controls, (319) 937-5700, www.whiteoakcontrols.com

WIKA Instrument Corp., (888) WIKA-USA, www.wika.com

Wilkes & McLean Ltd., (847) 860-0260, www.wilkesandmclean.com

Williams FluidAir Corp., (905) 831-3222, www.williamsfluidair.com

Winters Instruments, (716) 874-8700, www.winters.ca

Woodward HRT, (661) 702-5224, www.woodward.com/DirectDriveServovalves.aspx

World Wide Fittings, (847) 588-2200, www.worldwidefittings.com

World Wide Metric, (732) 247-2300, www.worldwidemetric.com

WorldWide Electric Corp., One Grove St., Pittsford, NY 14534, (585) 641-6430, Fax:(800) 711-1616, www.worldwideelectric.net

Y2K Fluid Power, (605) 338-9982, www.y2kfluidpower.com

Yates Industries Inc., 23050 Industrial Dr. E., St. Clair Shores, MI 48080, (586) 778-7680, Fax:(586) 778-6565, sales@yatesind.com, www.yatesind.com

Young Powertech Inc., 3060 Plaza Drive #107, Garnet Valley, PA 19061, (610) 558-0760, Fax:610-558-0762, info@yptius.com, www.yptius.com

Young Touchstone, (414) 768-7425, www.youngtouchstone.com

Yuken Kogyo Co. Ltd., (219) 465-4197, www.yuken-usa.com

Z & Z Mfg. Inc., 4765 E. 355 St., Willoughby, OH 44094, (440) 953-2800, Fax: (440) 953-2811, info@z-zmfg.com, www.z-zmfg.com

Zaytran Inc., (440) 324-2814, www.zaytran.com

ZEKS Compressed Air Solutions, (610) 692-9100, www.zeks.com

Zero-Max Inc., (763) 546-4300, www.zero-max.com

Zinga Industries Inc., (608) 524-4200, www.zinga.com

ZMC Corp., (760) 471-0440, www.zmccorporation.com

ZSI Inc., (734) 844-0055, www.cushaclamp.com