Hydraulics is the technology of controlling pressurized fluids to create force and motion. Parker hydraulics enable and improve machinery performance.
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Systems Integrator Develops Systems for Rail in Czech RepublicSince 1977, Chvalis, a premier distributor of Parker Hannifin based in the Czech Republic, has been focusing on the development and construction of hydraulic systems for the needs of general industry and mechanical engineering, working toward modernizing the Czech Republic. One specialty of the company is providing technical solutions and delivery of hydraulics for railway vehicles such as diesel locomotives and railcars. This includes not only new hydraulic systems but also modernization and reconstruction of obsolete vehicles. 
About Chvalis 

Chvalis is an expert on delivering turnkey solutions according to rail manufacturer's specifications, including delivery, installation and commissioning. Chvalis has been using Parker's products since 1992 in its systems for their unmatched quality, reliability and security. Components also meet the most demanding certifications. In the railway industry, Chvalis is the holder of the Certification of Technical Competence of the Czech Railways supplier and the SŽDC Supplier's Certificate.


Thanks to its extensive network of local branches, which are always associated with the ParkerStore service and ParkerStore sales hydraulics and tires, Chvalis is able to provide rolling stock operators 24-hour warranty and post-warranty service. The ParkerStore retail locations are fully equipped for the production of hydraulic hoses and are certified by the "ParkerStore Hose Certification Workshop." 


Exceptional order for CZ LOKO 

Until 2013, Chvalis supplied hydraulic systems only for auxiliary drives, such as compressor drives for compressed air production; the drive for the combustion engine cooling fans and the electric alternator drive for the production of electric motors. In 2013, the company received a call for a comprehensive design and solution for the supply of a complete hydraulic traction drive, including auxiliary drives for 35 units of MUV series 74.02 001-035 series, for CZ LOKO, the manufacturer and supplier of Czech Railways - SŽDC. 


Innovative open hydraulic system 

Chvalis has developed a technical solution for its own drive - an unconventional way of using its own innovative, open-circuit hydraulic system instead of competing with a preferred closed circuit. The system, while technically more demanding, precisely and comfortably addresses all the requirements of all traction control conditions controlled by the parent electronic control system of the vehicle. In addition, the circuit allows for hydraulic braking, which was used for the cruise control system. This makes the work of the drivers more efficient and saves the cost of the vehicle operators, reducing the wear of the brake discs of the standard pneumatic braking system of the vehicle. The standard brake is used most of the operating time, using this circuit for braking, until the vehicle stops. 

3D-CAT motor assembly with hydraulic drive CHVALIS

Hydraulic circuits are built using the Parker product portfolio, including Ermeto E02 pipe systems and hose systems from certified hoses for rolling stock. These hydraulic circuits, mainly PV-plus piston control pumps in conjunction with the  F11, F12, F1, F2, and F14 hydraulic motors of the V14 series, deliver a minimum fault, provide high reliability and long service life.

Valve block of hydraulic traction drive CHVALISThanks to previous experience with the 35-piece MUV74.02 series, Chvalis was asked by CZ LOKO's customer for the design and delivery of a complete hydraulic traction drive and auxiliary drives for a new series of 50 MUV 75.00 Universal Motor Vehicles. This new unit had the requirement to maintain the same hydraulic traction drive that has proven itself in the past series. In addition, the requirement to increase the hydraulic proportional brake power and increase the number of auxiliary hydraulic circuit circuits has been accepted: hydraulic hand, grass mower, hydraulically independent trolley tipping system, and suspension lock. 

Vehicle MUV 75.001 - at prototype tests at CZ LOKO manufacturer Jihlava


After the demanding testing of the first prototype in December 2017, the production of a 50-piece series of cars was launched in January 2018, again using the innovative Chvalis hydraulic system with proven hydraulic components from Parker.



Headed to InnoTrans?

InnoTrans is the leading international trade fair for transport technology and takes places every two years in Berlin, Germany. Sub-divided into the five trade fair segments Railway Technology, Railway Infrastructure, Public Transport, Interiors and Tunnel Construction, InnoTrans occupies all 41 halls available at Berlin Exhibition Grounds. The InnoTrans Convention, the event’s top-level supporting programme, complements the trade fair.

A unique feature of InnoTrans is its outdoor and track display area, where everything from tank wagons to high-speed trains is displayed on 3,500 metres of track. Visit Parker at Booth 206, Hall 10 or learn about our innovations to keep you on track on our solutions page



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Piston Pumps Deliver New Levels of Efficiency to Oil & Gas Market Hydraulic Pump and Power SystemsOver the last several years, the trend in the oil and gas market has been the near constant decrease in oil prices. As prices continue to drop, companies must find ways to remain profitable by streamlining costs. Design engineers are continually seeking more efficient technologies that can provide the same production capabilities while lowering the cost of operation.

Axial piston pumps deliver efficiency

Parker axial piston pumps provide a new-found efficiency. The P1 and PD Series Pumps are a step above the competition because of their energy recovery feature. This feature greatly reduces energy expenditure which saves cost. The pumps are designed to function as a pump to raise the rod string, then as the rod string gravity lowers, the pump is designed to go over center and work as a motor to recover the kinetic energy, which can then be used when raising the rod string or putting the energy back to the grid. In addition, this design allows the pumps to meet duty cycle requirements in applications where competitive products cannot accomplish this.

The P1 and PD series also have exceptional bearing life, which allows it to last longer than competitive product. This reduces down-time and the total cost of ownership. In an industry where down time is extremely costly and operating costs are critical, this feature is invaluable.

Axial piston pumps with electronic controls

The P1 and PD medium pressure axial piston pumps utilize electronic control systems to optimize performance with the ability to work with their own ECU or directly with the machine or vehicle’s ECU. The pumps ECU even feature a CANbus interface to support whole-vehicle CANbus systems.

Besides electronic controls, the P1 and PD series offer a broad range of controls, including load sensing capabilities. In oil and gas applications where there can be wide fluctuations in flow and pressure, load sensing controls can save considerable amounts of input power. A load-sensing controlled variable pump eliminates most inefficiencies created by fixed displacement pumps. This reduces the amount of energy lost when the pump is not operating at maximum flow and electronic controls just take that one step further minimizing losses even more than a load sense control.

Low Noise Applications

Piston Pumps Deliver New Levels of Efficiency to Oil & Gas Market - P1 PD pump example - Parker HannifinAs the public continues to demand a lower dependence on foreign sources of oil, companies are hastily trying to find domestic reserves in commercial quantities. This has forced companies to look for and produce oil and natural gas in locations previously thought to be too close to residential and commercial areas, greatly increasing the need for low-noise equipment due to regulations of operating in such areas.

The unique design of the P1 and PD allow them to excel in low-noise applications. They provide exceptional motor function, while leading the competition in noise reduction. They provide such low noise output that they can be used in a wide array of new low noise applications that have never been tapped due to limitations of other products, while still being cost competitive and highly efficient.

P1 and PD Piston Pumps are now available for purchase on parker.com. Simply add products to your cart for shipment from a Parker Distributor.


Piston Pumps Deliver New Levels of Efficiency to Oil & Gas Market - Keith McDonald, product manager, Hydraulic Pump and Power Systems Division, Parker Hannifin CorporationArticle contributed by Keith McDonald, product manager, Hydraulic Pump and Power Systems Division, Parker Hannifin Corporation.





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Utilizing Video Input to Improve Operational Safety of Heavy Equipment Electronic Controls DivisionThe ability to see behind a machine and work area is crucial to improve safety in the operation of heavy equipment and machinery.  Just as in automobiles, the capability to see behind a mine haul truck, fork lift, reach stacker or other machinery is important when maneuvering. Additionally, the ability to see the work area including the fork placement on a fork lift, grain conveyor on a harvester or the top hatch on a refuse side loader truck is also important for safety and to help improve operator productivity. Having a camera in place to see if the conveyer is clogged or if the top hatch is blocked can help reduce time, as well as allowing the operator to see potentially dangerous or damaging conditions before they become critical.

More and more heavy equipment, construction machinery, specialty trucks and agriculture equipment are using operator displays in the cab to improve the machine interface. Although dedicated video screens are readily available, having an additional screen for just video, adds cost and can inhibit the operator’s visibility. The ability to integrate video signals onto screens offers a cost-effective solution, as well as improving operator visibility by reducing the number of screens in the cab.

The PHD50 and the PHD70 touch screen displays offer the ability to not only perform the operator interface for engine and machine diagnostics, status and configuration, they also support video input directly to the screens. The PHD50 supports a single video feed, while the PHD70 support two video feeds.

Both PHD models can perform logic and calculations to allow the video screen to show dynamically, based on events or fault conditions. For example, if the loading arms on a refuse truck are raised, but the top hatch is closed, the top hatch video camera feed can automatically appear on the screen to inform the operator of the condition. When a mine haul truck is put into reverse travel, the backup camera feed can automatically appear, or if the chipping wheel on a whole tree chipper signals an overload, the work space camera can automatically appear to show the operator what is causing the overload. This can dramatically improve the machine efficiency by allowing the operator to proactively deal with possible dangerous or work stopping conditions.

Utilizing Video Input to Improve Operational Safety of Heavy Equipment

Utilizing Video Input to Improve Operational Safety of Heavy Equipment


In this example, the PHD50_Camera.zip and PHD70 Camera.zip files include an example application program that shows how to implement the single video input into the PHD50 and both video inputs in to the PHD70. In addition to the video input(s), the example has implemented the follow features:

  • Flip the video screen for backup camera orientation.
  • Backlight adjustment with Auto Backlight for night and day operation.
  • Selection button to select video 1 or 2 on the PHD70.
  • Entering sleep mode and using a screen touch as a wake signal for power saving operation.
  • This example uses an NTSC analog camera, but PAL is also supported for broader market opportunities around the world.

This application example can be used as is for basic video screens or can be modified or included in another PHD application to incorporate the advantages of video screens into an application to accompany engine and machine parameter settings, showing fault codes and overall status and gages.  The example contains the graphical content for the video feed selection, the script to invert the video image and the screen to set the backlight intensity using Crank Storyboard and functionality written in Lua script.

To learn more about how PHD displays can help equipment operators, view our product literature, technical specifications and reference materials.

Utilizing Video Input to Improve Operational Safety of Heavy Equipment

Article contributed by Edward Polzin, regional application engineer - central,

Electronic Controls Division, Parker Hannifin Corporation.




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 Most people enjoy theme parks as a place to get away from work, but for those in the hydraulics industry, they are a place to demonstrate their expertise. Behind many of the rides that make your stomach drop or your eyes blink in amazement, Parker's accumulators are picking up the stresses and enhancing the performances of hydraulic technology.

Behind the scenes, there is complex machinery that must run precisely and smoothly to ensure safe and reliable operation. Whether you are splashing through water, sailing above the tree lines, or being wowed by animations and simulations, powerful equipment that depends on the science and engineering of hydraulics is enriching your activities.  And, many of these large, powerful hydraulic systems rely on accumulators; hidden from the public view, but critical in their roles.      


The role of accumulators

Typically, accumulators installed in hydraulic systems store energy to either provide an extra boost of power or absorb energy to smooth out pulsations. One of the world's largest manufacturer of accumulators is Parker's Accumulator and Cooler Division. According to Jeff Sage, product sales manager, the Parker accumulators used in theme parks are gas-charged and are either bladder accumulators or piston accumulators. Parker manufactures both types and has the engineering expertise to recommend which kind best fits the requirements of a particular ride.

Bladder accumulators are cylinders that contain a rubber bladder (Figure 1). Hydraulic oil is kept under pressure when the bladder is inflated with an inert compressed gas, often nitrogen. When a ride needs a quick burst of power, a valve opens and releases the pressurized hydraulic fluid.



Piston accumulators are metal tubes with an enclosed piston(Figure 2). One side of the piston is charged with a pressurized gas and the other side with hydraulic oil. When the ride requires additional power, the pressurized gas pushes against the piston which forces hydraulic oil back into the ride’s power unit.

Watch it in action:


Accumulators often play valuable roles in hydraulic systems that power rides for a variety of reasons. As you can imagine, moving multi-ton cars, coasters, and props, often times with rapid acceleration in minimal time, requires extreme bursts of force. Delivering this concentrated force is taxing on hydraulics systems and can cause jerky movements. Accumulators work to absorb these extreme pressures and movements, store energy and keep performance consistent – delivering the extra “push” when a hydraulics system needs it.

Often there are many accumulators used on each ride. For example, on motion-simulator rides, which have become quite popular since the 1980s, many accumulators are used. These are amazing rides where people feel all the shakes, rattles and rolls depicted in a movie shown on a large screen. A big surge of energy is needed to move the platform. Within these rides there are 24 platforms, each with banks of 10-gallon bladder accumulators. Each time the platform moves, a quick burst of energy is needed. These accumulators provide the high acceleration needed to make the ride exciting and memorable.


Safety factors

Safety, of course, must be at the forefront of manufacturing accumulators. A ride that breaks down can cause injuries or worse. Most bladder accumulator failures come from the bladder failing. Parker accumulators minimize the issue by manufacturing its own bladders for quality control reasons. This is not common and differentiates Parker from the competition.

Knowing how important the chemical process is in the making of these bladders, the company has its own chemist, buys the rubber and mixes the bladder compounds. With everything controlled and created in-house, this helps Parker produce accumulator bladders that are of the highest quality and reliability.

And when a piston accumulator fails it is typically a result of a leak in the rubber seal located on the outer cylinder of the piston. A proper functioning seal separates the gas from the oil. Gas molecules are very small and can penetrate through the rubber seal. Parker applies its expertise in rubber composition to develop seals that minimize the gas permeation, thus extending the life of the piston accumulator.


More on reliability

Nothing stops the fun at a theme park like a sign at a ride’s entrance that says, “OUT OF ORDER.”

Carlos Aguirre, a Sales and Systems engineer at Bernell Hydraulics Inc., uses Parker because of their accumulator expertise, reliability, and service. Bernell and Aguirre have a long history of working with the nation’s top theme parks and using Parker's accumulators to keep the attractions running smoothly and safely. Aguirre and his teams work overnight after theme parks close, so it’s essential that he chooses trusted vendor partners that can deliver dependable parts when they are needed. While most of Aguirre’s theme park projects have used bladder accumulators, new projects are requiring piston accumulators. 

“Park patrons want to enjoy their favorite rides. I need quality parts delivered on time so we can get the work done at night and have the ride ready to roll when the gates open in the morning. I like the expertise Parker offers on either type. One call and I get the information I need to make theme parks fun and safe for all.”

Carlos Aguirre, sales and systems engineer at Bernell Hydraulics Inc.

The next time you’re at a theme park waiting to ride, we hope that the greatest energy is the energy of the moment. However, you might take a moment to appreciate the extreme amounts of force and energy required for your favorite ride to give you a hair-raising experience. For our accumulators, handling the exciting extremes is a walk in the park.

If you would like more information about accumulators, visit Parker Accumulator and Cooler Division.


Jeff Sage, product sales manager, Parker Hannifin Accumulator and Cooler Division Article contributed by Jeff Sage, product sales manager, Parker Hannifin Accumulator and Cooler Division.







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Using a Mobile Display as a Dynamic Numeric Keypad Input Device Feature Photo Electronic Controls Division

Control of vehicle speed is important to equipment operators. The ability to accurately set the speed of a conveyor or roller in applications such as road paving or striping, crop sprayers and sugar cane harvesters is essential to help optimize productivity and help reduce waste. Additionally, the ability to enter a user ID, PIN or password is often a requirement to help ensure only authorized users have access to operate heavy equipment. Although large, more complex displays can perform these basic functions, they are often not cost effective or small enough to be a good application fit.

  A  cost-effective, dynamic solution

The PHD28 touch screen display offers a cost-effective replacement for a traditional, robust keypad in a dynamically configurable platform. In addition, the PHD28 has enough built in processing power to perform basic calculations, check entry limits of values entered, rescale values or even change the value based on an incoming CAN message or input signal. With its compact, 2.8-inch size, it fits well in many consoles and dashboards without compromising valuable space.

Using the PHD28 in conjunction with other Parker electronic products where a simple to use number entry system can control complicated systems.

  Numerical entry to control vehicle speed

When control of conveyor speed is needed to perform the functions of the vehicle, a PHD along with an IQAN controller can provide this functionality as a low cost and efficient solution.

For example, the PHD28 programmed as a numeric keypad will allow the operator to select the desired conveyor speed and then transmit that value to an IQAN MC43 controller to control the vehicle.  This instance can be expanded to any of the PHD family displays as well as the IQAN family of controllers.

Using a Mobile Display as a Dynamic Numeric Keypad Input DeviceIn this example, a value is entered by the user and if within range, the target speed is transmitted over the CAN bus to the IQAN controller.  To confirm the value, the feedback from the IQAN controller is shown in the top right of the screen and is used to control the vehicle speed. 

The IQAN controller can then communicate with the diesel engine and brake control system to regulate vehicle speed.  When vehicle speed does not match the input value from the keypad, the IQAN controller can notify the engine to speed up if the vehicle is moving too slow.  If the vehicle is moving too fast, the IQAN controller can activate the brake system so the vehicle will slow down. 

Vehicle speed can be measured using a sensor such as a Parker GS60 speed sensor.  The frequency output from the GS60 can be connected to the IQAN controller, which would use a PID loop to control the engine and braking system to maintain the desired speed.

If an operator must adjust vehicle speed, they can enter the appropriate speed value or use the up and down arrows to adjust the current value. 

Parker offers the keypad program for the PHD eliminating the need for programming in this specific configuration.  An IQAN 5 external function and example application is also supplied to make it easy to integrate with the rest of the IQAN application. If a custom design or look is desired, the PHD28 can be programmed to fit that application using Crank Storyboard software.

Using a Mobile Display as a Dynamic Numeric Keypad Input Device example Electronic Controls Division

In the example to the right, the screen shows a numerical keypad where the user can enter a numerical value with 0.1 precision.  The user enters the value and then has the option to select cancel, revert to the previous value, or enter to accept the value.  Upon acceptance, the value is then transmitted to the system controller via a J1939 message.  The user also has the option to increment and decrement the current value using the up and down arrows.

This example is configured so that the system controller can send an acceptable maximum value as a variable to the PHD to qualify the input value is within range.  Then the PHD gives a color coded visual indication to the user the value was accepted.In the example above, the screen shows a numerical keypad where the user can enter a numerical value with 0.1 precision.  The user enters the value and then has the option to select cancel, revert to the previous value, or enter to accept the value.  Upon acceptance, the value is then transmitted to the system controller via a J1939 message.  The user also has the option to increment and decrement the current value using the up and down arrows.

The transmitted J1939 message in this example uses PGN 0xFF00 with two parameters: the entered value and a Boolean search that is active while the OK button is pressed.  The resulting J1939 message in the example also uses PGN 0xFF00 with two parameters:  the maximum acceptable value and a feedback value so the system controller can acknowledge that entered value was accepted.

This application example can be used as is for a basic keypad device, can be modified to accommodate desired form and function or can be used in an existing PHD application to add keypad functionality.  The example contains the graphical content, screen layout using Crank Storyboard and functionality written in Lua script.

In many cases, the content of the keypad should be adjusted for regional content, customer color theme or operating mode. These dynamic changes cannot be accomplished on a traditional mechanical keypad.

  Products and features:



  PHD28 Display

  Easily enter and change values in system

  IQAN-MC4x Controller

  PHD program and IQAN function group available

  GS60 Speed Sensor

  Robust, outdoor rated products



To learn more about PHD Displays, view our product literature, technical specifications and reference materials.   


Using a Mobile Display as a Dynamic Numeric Keypad

Article contributed by Edward Polzin, regional application engineer - central, Electronic Controls Division, Parker Hannifin Corporation





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How New Winding Technology for Paper Converting Delivers Energy Savings - Paper winder - Parker HannifinThe advancements in hydraulics and variable speed drives (VSD) were running in parallel for many years but on opposite sides of the fence from each other in solving paper converting industrial applications. Once the engineers on both sides met in the middle and shared their knowledge, a door opened to a new way of thinking and problem-solving. Combining VSD and hydraulics was difficult at first; the unforgiving nature of positive displacement pumps, the non-compressibility (incompressibility) of the fluids, demanded a different solution than what VSD engineers had experienced with more forgiving lower pressure centrifugal pumps. The combination of hydraulics and VSD has created a new type of system with lower noise, fewer components, and higher energy efficiencies. 


 Download our white paper and learn how Drive Controlled Pump (DCP) technology can make center winders the ideal winding technology for the paper converting industry.


Drive controlled pump

Hydraulic systems are known for their ability to deliver significant power density in a small package. Electric motors and variable speed drives are known for their programmability and responsiveness. Dating back to the 1990s, hydraulic and drive system engineers could see the potential for combining the two technologies. Historically, the motion control industry has had limited success in combining the technologies. However, in today’s manufacturing environment, the higher cost of electrical power, the increasing global concern for the CO2 footprint and the need for quieter industrial solutions offer opportunities to reevaluate the combined technology. Today, the advancement in new Variable Frequency Drives (VFD) control algorithms, faster programmable VFDs and more efficient hydraulic pumps specifically designed for variable speed applications allows our engineers from both technologies to work together with greater opportunities for success by implementing an ideal technology known as Drive Controlled Pump technology (DCP).


DCP winding solution

Traditionally, electromechanical drive systems are used for the majority of converting line’s center winders or combined center surface winders. These drive systems use electric motors larger than the web horsepower by the factor of their buildup ratio. DCP can keep the electric motor size close to its web horsepower by eliminating the buildup factor in a winding application. This takes advantage of the continuously variable flow and pressure feature of an electronically controlled variable displacement hydraulic pump operating at variable radial speeds.

Taking advantage of electric drive and hydraulic technology yields a positive outcome in winding and unwinding techniques. DCP technology allows us to create a wide constant HP range and trade speed for torque during the buildup process while reducing the size requirements for the electric motor. Since this technology operates the hydraulic pump at a variable speed; it uses fewer and simpler hydraulic valves. DCP hydraulic systems are less complex and more efficient than traditional hydraulic systems; it operates at much lower noise and temperatures resulting in quieter and cooler surroundings.


DCP winding features

This system is very flexible; a variable displacement motor and a fixed displacement pump can be used to achieve the same results. The following diagrams show the control schematic of a DCP winding system using a variable displacement hydraulic motor and a fixed displacement open loop pump.



The system can also be adapted to closed loopX hydraulics and unwinding applications quite easily as shown below.



 Paper converting lines employ surface, center, and center/surface combination winders and each winding technique has inherent benefits and limitations. Download our white paper and learn more about how Drive Controlled Pump (DCP) technology can make center winders the ideal winding technology for the paper converting industry.





Rashid Aidun, application engineer, Parker HannifinArticle contributed by Rashid Aidun, application engineer, Parker Hannifin.







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