variable swash plate hydraulic pump quotation

All control is achieved by the proper positioning of the swash plate. This is achieved by a servo piston acting on one end of the swash plate working against the combined effect of the off-setting forces of the pistons and centering spring on the other end. The control spool acts as a metering valve which varies the pressure behind the servo piston. The amount of flow produced by the Parker Piston Pump is dependent upon the length of stroke of the pumping pistons. This length of stroke, in turn, is determined by the position of the swash plate.

Maximum flow is achieved at an angle of 17°. The rotating piston barrel, driven by the prime mover, moves the pistons in a circular path and the piston slippers are supported hydrostatically against the face of the swash plate. When the swash plate is in a vertical position, perpendicular to the centerline of the piston barrel, there is no piston stroke and consequently no fluid displacement. When the swash plate is positioned at an angle, the pistons are forced in and out of the barrel and fluid displacement takes place. The greater the angle of the swash plate, the greater the piston stroke.

The centerline of the pumping piston assembly is offset from the centerline of the swash plate. Therefore, as shown on the accompanying Figure 1A, the pistons’ effective summation force tends to destroke the swash plate to a vertical (neutral) position. This destroking force is balanced as the swash plate is angled by the force of the servo piston.

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The displacement of a pump is defined by the volume of fluid that the gears, vanes or pistons will pump in one rotation. If a pump has a capacity of 30 cm3, it should treat 30 ml of fluid in one rotation.

In axial piston variable pumps, the flow is proportional to the drive speed and the displacement. The flow can be steplessly changed by adjusting the swivel angle. Axial piston variable ...

... axial piston pump type V60N is designed for open circuits in mobile hydraulics and operate according to the swash plate principle. They are available with the option of a thru-shaft for operating additional ...

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Axial piston twin flow pump. With a very high performance in all job conditions. Due to its twin flow configuration this pump allows a great variety of solutions in different job applications.

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... customer system options for mechanical, hydraulic and electric input solutions are available. Further special regulating features like torque control and pressure cut-off are also available. The reliable ...

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... PVG is a variable-displacement axial-piston pump designed to take on your most demanding applications. It offers high-pressure, superior performance in a compact design ...

Variable displacement pumps in closed loop; 3 basic design units and 8 max. displacement sizes of 14, 18, 21, 28, 35, 46, 56, 64 cc/rev; various control options; max. ...

Parker P2/P3 High Pressure Axial Piston Pumps are variable displacement, swashplate piston pumps designed for operation in open circuit, mobile hydraulic ...

... Series pump offers variable displacement axial piston pumps for open-circuit applications. Featuring a compact footprint and continuous operating pressure ...

The InLine variable displacement pump type V30D and V30E work according to the swash plate principle and are intended for open circuit operation in industrial and mobile hydraulics. There is also an option for a thru-shaft for flange mounting additional variable and fixed displacement pumps. Type V30E is intended as successor of V30D, where the completely new development allowed realizing state of the art pump design. This concerns primarily the optimization of self-suction speed rating, minimized noise level, weight, and pulsation as well as increased service life. These pumps are suited for a wide range of applications due to their low running noise and various pump controllers. Hydraulic circuits where several outlet flows are required can be fed either by one individual pump or a multiple pump. Main benefit of these pumps are the sturdy design, the good performance /weight ratio, long service life due to oversized bearings, and the swash plate angle indicator.

Variable Displacement Axial Piston Pump, Pressure Rating of 6,090 psi. The C Series Variable Displacement Axial Piston Pumps are engineered for heavy-duty mobile equipment applications. Pumps offer a pressure rating of 6,090 psi, durable construction and a compact footprint. C Series variable displacement piston pumps have been designed for use in closed circuit hydrostatic applications. […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 17 to 28 cm³ (1,04 to 1,71 in³), Continuous 280 bar (4060 psi), Pressure Intermittent 300 bar (4350 psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series HM P1A are designed to operate in a closed circuit. The available control systems make it easy to use these […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 28 to 36 cm³ (1,71 to 2,20 in³), Continuous 280 (4060 psi), Pressure Intermittent 300 bar (4350 psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series HM P1M is designed to operate in a closed circuit. The available control systems make it easy to use these pumps in […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 7 to 18 cm³ (0,43 to 1,10 in³), Continuous 210 bar (3045 psi), Pressure Intermittent 230 bar (3335 psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series HM PLB is designed to operate in a closed circuit. Displacement range 7cc thru 18cc, R or L hand rotation, single […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 7 to 18 cm³ (0,43 to 1,10 in³), Continuous 250 | 230 bar (3625 | 3335 psi), Pressure Intermittent 280 | 250 bar (4060 | 3625 psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series HM PO is designed to operate in a closed circuit. The available control systems […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 17 to 34 cm³ (1,04 to 2,07 in³), Continuous 280 bar (4060 psi), Pressure Intermittent 300 bar (4350 psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series HM PS is designed to operate in a closed circuit. The available control systems make it easy to use these pumps […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 9+9 to 16+16 cm³ (0,55+0,55 to 0,97+0,97 in³), Continuous 280 bar (4060 psi), Pressure Intermittent 300 bar (4350psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series HM PX is designed to operate in a closed circuit. The available control systems make it easy to use these pumps in any application for industrial and […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 7 to 18 cm³ (0,43 to 1,10 in³), Continuous 250 | 230 bar (3625 | 3335 psi), Pressure Intermittent 280 | 250 bar (4060 | 3625 psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series HM PZA have been designed to operate in a closed circuit. The available control systems […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 14 to 23 cm³ (0,85 to 1,40 in³), (Swashplate 14,5 | 19 | & 18), Continuous 250 bar (3625 psi), Pressure Intermittent 280 bar (4060 psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series HP P2 is designed to operate in a closed circuit. Control Systems are available […]

Closed Circuit Axial Piston Pumps, Variable Displacement , Max. Displacement from 17cc to 34 cc, SAE B Flange, (Swashplate 18 | 19 | 18 | 18 | 18°), Pressure Intermittent 300 (bar), 4350 (psi). The axial piston pumps series HP P4 34•46•50•58•65 is designed to operate in a closed circuit, for applications at medium pressure. Control […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 55 to 78 cm³ (3,35 to 4,76 in³), (Swashplate 16,3 | 17,3 | 17,7 °), Continuous 420 | 400 bar (6090| 5800 psi), Pressure Intermittent 450 | 420 bar (6525 | 6090 psi), (Power-Transmission Hydrostatic Transmission) The axial piston pumps series HP P6 series is designed to operate […]

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 82 to 125 cm³ (5,0 to 7,6 in³), (Swashplate 18,0, 16,5, 20,0°), Continuous 400 bar (5800 psi), Pressure Intermittent 420 bar (6090 psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series HP 8 82•100•125 is designed to perform in closed circuit for high pressure operations. The various control […]

The self-regulating HPR-02 is a high perssure axial piston pump in a swash plate designed for open loop systems. With both clockwise and counter clockwise rotation, it is self priming at high nominal speeds.  It can reach a higher rotating speed by tank pressurization or swash angle reduction. It is a good fit for application […]

Variable Displacement Pump for Closed Loop Operation, Displacement 54.7 to 281.9 CC/Rev, Max. Operating Speed 2400 RPM to 3900 RPM, Max. Pressure 500 Bar, Nominal Pressure 450 Bar, Power Take-Off (PTO) Flange, Internal Gear Pump (IGP) and External Gera Pump (EGP) Available. The HPV-02 variable pump is an axial piston pump designed for high pressure […]

Open Loop Variable Displacement Axial Piston Pump The K3V/K5V Series are variable displacement axial piston pumps of swash plate design, suitable for use in mobile applications. Various rotary group layouts, tandem type with PTO and parallel type are available to respond to applications. The K3V/K5V Series has a high power density, high suction capability, wide […]

Swash Plate Variable Displacement Axial Piston Pump. The K3VG Series are variable displacement axial piston pumps of swash plate design for industrial equipment. The K3VG Series are available in size ranging from 63 to 560 cm³/rev with various control options including a highly precise electro-hydraulic servo regulator “ILIS”. Main features of the K3VG Series includes […]

Variable Displacement Swash Plate Design, Open Loop. The K3VL Series – medium pressure, open circuit, axial piston pumps are designed for mobile, industrial, and marine applications. The pump’s rotating groups are based on the proven design of the K3V and K3VG pumps. K3VL pumps are available in nominal displacements ranging from 1.71 to 12.20 in³/rev […]

Variable Displacement Swash Plate Design, Open Loop, Displacement 50 (cm³) to 150 (cm³). The K3VLS series are variable displacement axial piston pumps of swash plate design, suitable for use in mobile applications and industrial vehicles with medium pressure hydraulic systems. The K3VLS pumps enable flexible configuration in a wide range of applications with their compact […]

Low Noise Variable Displacement Axial Piston Pump. The K7V Series are variable displacement axial piston pumps of swashplate design, suitable for use in mobile applications. A long life is obtained by adopting large capacity of bearing and thicker shaft which reduces the load on the edge of bearing rollers. The power density if 1.5 times […]

Swash-plate Axial Piston Pump The K7VG high-pressure swashplate pump developed for general industrial machinery use and is based on long and rich experience. The adoption of the high-load bearing and friction-free contacting mechanism of shoes has achieved high reliability and long life. The unique compact rigid housing construction in addition to the semi-cylindrical swash-plate and […]

Variable Displacement Swash Plate Design, Closed Loop. The K8V series with a range in pump size from 71 to 130 cm3/rev are equipped with electric or hydraulic pilot displacement control. The K8V series pumps, having the integrated components required for a closed system, such as a charge pump, high and low-pressure relief valves, and a […]

Bent Axis Variable Displacement Axial Piston Pump. The LVP 017 Series are manual variable displacement axial piston pumps of bent axis design for high-pressure jacks. The bent axis type axial piston pumps have features such as high efficiency and long life. They can operate for long periods under severe conditions: high-pressure continuous drive, use of […]

Variable Displacement Axial Piston Pump The LXV/LZV series are variable displacement axial piston pump of bent axis design and have heavy duty bearings to achieve long life. They can operate for long periods of time under severe conditions: high-pressure continuous drive, use of fire-resistant fluid, etc.

Variable Displacement Closed Circuit Axial Piston Pumps, Displacement 21 to 37 cm³ (1,28 to 2,26 in³), (Swashplate 18°), Continuous 250 bar (3625 psi), Pressure Intermittent 300 bar (4350 psi), (Power-Transmission Hydrostatic Transmission). The axial piston pumps series M4 PV is designed to operate in a closed circuit. Control systems actually available are making easy to […]

Variable Displacement Axial Piston Pump, Operating Pressure of 4,060. Variable, swashplate piston pumps designed for operation in open circuit, mobile hydraulic systems. The perfect choice when it comes to cost-saving installation as well as high productivity and power density. Displacement from 60 to 145 cc/rev. The P2/P3 Series has been designed to meet the specific […]

Medium Pressure Super Charged Pumps, Pressure Rating 3,000 psi. The PAVC Medium Pressure/Super Charged Pumps provide reliable high-speed operation. With a pressure rating of 3,000 psi, they are ideal for a variety of medium pressure mobile and industrial applications. Featuring a flexible, compact design, Pavc Medium Pressure Pumps deliver a reliable,easy-to-use solution for a wide […]

Variable Displacement Piston Pump, Operating Pressure of 4,060 psi. The PD Series pump offers variable displacement axial piston pumps for open-circuit applications. Featuring a compact footprint and continuous operating pressure of up to 4,060 psi, PD pumps provide quiet operation and efficient control. The PD Series of Open-Circuit Piston Pumps boost productivity in medium pressure […]

Variable Flow, High-Pressure and High-Speed, For Open Circuits SAE, ISO, DIN), Continuous Pressure Rating up to 6,000 PSI, Intermittent Pressure Rating up to 7,250 PSI, Five Frame Sizes (80 cc – 260 cc), Maximum Speed of 2,550 RPM. The Premier Series features superior design and simplified maintenance; the Premier Series delivers high-pressure variable piston pumps […]

Variable-Displacement Axial Piston Pump with Fast Control Response. The PVG is a variable-displacement, axial piston pump with fast control response. The PVG thrives on low viscosity fluids and is available in a variety of control and porting options. It is designed to be a high-performance solution for demanding applications. PVG open loop, axial piston hydraulic […]

Variable Axial Piston Pump with Longitudinal Controls The PVK pump line consists of three sizes of variable-displacement, open-loop, axial-piston pumps. The PVK is unique from other variable pumps because it has longitudinally-mounted controls. It is recommended that legacy PVK pumps be replaced by the current PVG pump line. Available in two frame sizes and three […]

A Versatile Pump with a Modular Design. The PVM line of variable-displacement, axial-piston pumps is designed to adapt to your most demanding applications. Virtually indestructible, the modular PVM open-loop, axial-piston hydraulic pumps offer advanced engineering at an affordable price. Computer-optimized and with multiple controls available, PVM pumps deliver high performance in a compact design. Available […]

Variable Volume Displacement Piston Pump, Operating Pressure of 3,600 psi. The PVP Series provides durable variable volume piston pumps for medium pressure applications. With aa pressure rating of 3,600 psi and a wide range of controls, PVP pumps are efficient and reliable. The PVP Series is flexible and high-performing, resulting in increased uptime with fast […]

Axial Piston Variable Pumps, Operating Pressure Up to 420 bar. The PVplus (PV+) is an open circuit, variable swashplate piston pump. Optimized for heavy-duty industrial and marine applications. Operating pressures of up to 420 bar, high-speed ratings, a wide range of highly responsive controls, and a displacement from 16 to 360 cc/rev. The PVplus (PV+)  provides […]

The Flagship, High-horsepower Variable Displacement Pump. The PVV line pumps represents the pinnacle of performance in a variable-displacement, axial-piston pump. Designed for power and speed, PVV open-loop, axial-piston hydraulic pumps by delivering the punch that is required for large, heavy-duty systems. Utilizing advanced engineering, the PVV pump line delivers up to 560 horsepower – four […]

The Closed-loop Pump for Low-viscosity Fluids. Rugged and tough,  PVWC closed-loop, hydrostatic, axial-piston hydraulic pumps offer low horsepower for high-performance applications. The PVWC pump combines quiet operation, high efficiency and competitive pricing in a compact design. Capable of operating with low-viscosity or other special fluids, and with excellent contamination resistance properties, PVWC pumps feature a […]

Variable Displacement Cost-effective, Rugged Pump. The PVWJ is a variable-displacement, axial-pistol pump with medium control response. It thrives on low viscosity fluids and is available in a variety of control and porting options. The PVWWJ open loop, axial piston hydraulic pumps  are uniquely designed for enhanced stability and less maintenance in low to medium horsepower […]

Variable Displacement Pump for Ultra Low-lubricity Applications. The PVWW line of pumps provides excellent variable-displacement pumping with fluids with a high water concentration. The PVWW is available with a variety of control modules. PVWW open-loop, variable-displacement, axial-piston hydraulic pumps are uniquely designed for low-lubricity, low-viscosity applications, such as pumping water-based, and environmentally-friendly fluids. Available in […]

Axial Piston Variable Pumps, with Operating Pressure up to 6,100 psi. The VP1 hydraulic variable truck pump series has operating pressures up to 420 bar (6,100 psi) and speeds up to 3000 rpm. The VP1 pump is a robust design that provides circuit reliability for the most demanding truck applications. Sizes from 45 – 130cc. […]

THM Huade Hydraulics Private Limited is one of the largest manufacturing companies of China involved in the production of Hydraulic components for over 3 years. With approximately 25% share in the Chinese market and 5 plants for different product group, we have made our presence felt in the global market. To expand our business operations and cover the Asian market, we have entered in the Indian industry as M/s. THM Huade Hydraulics Private limited, Ludhiana. M/s Beijing Huade Hydraulics Industrial Group Co. Ltd is a Chinese state government owned company with a large production scale engaged in manufacturing and supplying of power units and hydraulic components based on technology of Rexroth, Germany. Our product range is only made to the highest quality and tested in the global market since 1978. The complete range of products offered by us includes Hydraulic Cylinder, Accumulators, Directional Control Valves, Cartridge Valves, Filter, Hydraulic Power Pack, Pressure Control Valves, Variable Displacement Axial Piston Pump, Flow Control Valves and Accessories, Proportional Valves, Bent Axial Piston Pump & Motor and Gear Pumps.

The working principle of A11VLO pump is that the displacement of the pump chamber is brought about by the movement of the pistons, so that the fluid is compressed and the fluid has pressure energy. It is a hydraulic component that provides pressurized fluid for hydraulic transmission. Its function is to convert the mechanical energy of power machines, such as motors and internal combustion engines, etc., into liquid pressure energy. The cam is rotated by the motor. When the cam pushes the pistons upwards, the sealing volume formed by the pistons and the cylinder decreases, and the oil is squeezed out of the sealed volume and discharged through the one-way valve to the desired place. When the cam rotates to the lower part of the curve, the spring forces the piston downwards to form a certain degree of vacuum, and the oil in the tank enters the sealed volume under atmospheric pressure. The cam keeps the piston moving up and down, the volume of the seal periodically decreases and increases, and the pump continuously sucks and discharges oil. The necessary condition is that the pump chamber has a sealed volume change.

Welcome inquiry us for Rexroth Axial Piston Variable Pump A11VLO series, like as A11VLO80, A11VLO107, A11VLO190, A11VLO130, A11VLO210, A11VLO260....., Heash Technique B.V. is your nice partner in hydraulic cooperation on now and future!

- Special adjusting device program with dynamic Positioning behavior and swivel angle sensor with Hall Effect for fully electronically controlled pumps.

An irregular performance of a mechanical-type constant power regulator is considered. In order to find the cause of an irregular discharge flow at the cut-off pressure area, modeling and numerical simulations are performed to observe dynamic behavior of internal parts of the constant power regulator system for a swashplate-type axial piston pump. The commercial numerical simulation software AMESim is applied to model the mechanical-type regulator with hydraulic pump and simulate the performance of it. The validity of the simulation model of the constant power regulator system is verified by comparing simulation results with experiments. In order to find the cause of the irregular performance of the mechanical-type constant power regulator system, the behavior of main components such as the spool, sleeve, and counterbalance piston is investigated using computer simulation. The shape modification of the counterbalance piston is proposed to improve the undesirable performance of the mechanical-type constant power regulator. The performance improvement is verified by computer simulation using AMESim software.

The pressure regulators of swashplate-type variable displacement axial piston pumps (VDAPP) control the swivel angle, which changes the amount of flow rate to hydraulic circuits. The pressure regulator is operating in accordance with the dynamic response of the discharge pressure, and it supplies pilot flow rate to the control piston which regulates the swivel angle of swashplate. The pressure regulator is mainly divided into the three types depending on the operating method, that is, a flat cut-off type, a differential cut-off type, and a constant power type.

The pressure regulators are usually used to save energy of hydraulic systems in the industrial field. As the hydraulic power unit used for movable equipment has increased, the pressure regulators have been applied in such systems in order to protect prime mover. Most movable hydraulic power unit consist of motor, pumps and reservoir (MPR). An overload of the pump can cause damage to the electric motor and its circuits under a variety of load conditions. To avoid these problems, power regulation of the pump is needed in order to respond to wide varieties of loads without exceeding the maximum power range of the prime mover. In this study, we applied the constant power regulator to the VDAPP so that the angle of the swashplate is automatically decreased according to an increase of the load pressure.

Recently, electronic regulators have been studied and commercialized [1–4]. However, the mechanical regulators are mainly applied in the industrial field because a proportional reducing pressure valve which is used as main part of the electronic regulator has relatively poor durability than mechanical regulator. In recently developed hydraulic regulator systems, both the electrical and mechanical regulators are applied to hydraulic regulator system. In those hydraulic regulator systems, the mechanical regulator is used as emergency equipment so that it only works when the electronic regulator fails. Due to the relatively exceptional durability, the mechanical regulator system is especially adopted to construction equipment and combat vehicles, which are used for long periods in poor conditions.

In Section 2, we present the structure and operating principle of a constant power regulator. A mathematical analysis for the AMESim model of a swash plate VDAPP is introduced in Section 3. In Section 4, we compare the simulation results with the experimental output to validate the simulation model. Then, the shape modification of the counterbalance piston is proposed and the effect of the improvement is verified by computer simulation. Our conclusions are given in Section 5.

A schematic diagram of a swash plate VDAPP with a constant power regulator is shown in Figure 1. Figure 2 represent hydraulic circuit of the constant power regulator system. The constant power regulator system consists of five parts, that is, a regulator assembly (A), a control cylinder assembly (B) which controls the angle of the swash plate, a counterbalance assembly (C), a swash plate (D), and a piston (E). As shown in Figure 3, the regulator assembly consists of a spool and sleeve. A flow area of the regulator system is determined by relative displacement between spool and sleeve. Figures 4 and 5 show the detailed structure of the control cylinder and counterbalance.

As shown in Figure 8, the swash plate is held in a certain swivel angle. In this area, the discharge pressure of the pump does not feed back into the control cylinder. This causes the swash plate to rotate in a maximum angular displacement. As a result, the pump can supply the maximum flow rate to a load system unless the discharge pressure of VDAPP is sufficiently increased to a certain level by a load. At the maximum flow rate section shown in Figure 9, the discharge flow rate cannot be feed into the control cylinder because the spool blocks the path of the sleeve.

The increased load pressure makes the spool move, and pilot flow rate is supplied into the control cylinder [7–9]. Then, the swivel angle is decreased as shown in Figure 10. By the kinematic constraints of the piston, the sleeve acts as a reaction force to the swivel torque. During this time, the swivel angle of the swash plate should be reduced gradually in order that the VDAPP can discharge the flow rate with constant power.

In the constant power area shown in Figure 11, the spool is moved by the pilot pressure which is equal to load pressure, and the spool displacement makes the flow path to the control cylinder open. Then, the flow is supplied to the control cylinder. Therefore, the swivel angle is decreased, and the discharge flow rate of the pump is reduced. When the swivel angle is decreased, the sleeve reduces or blocks the flow to the control cylinder by the movement of the counterbalance piston. Therefore, the displacement of the control cylinder is adjusted according to the load variation. Consequently, the increase of the load pressure decreases the discharge flow rate of VDAPP, and that makes output power of VDAPP constant because the output power of VDAPP is determined by the product of load pressure and discharge flow rate.

When the load pressure reaches a limit, the VDAPP makes the discharge flow zero by setting the swivel angle of swash plate vertically, as shown in Figure 12. In this section, the discharge flow rate from VDAPP is rapidly decreased because the sleeve stroke is blocked by the kinematic constraint of the regulator. Then, the VDAPP sets the swash plate vertically and cuts off the discharge flow rate, as shown in Figure 13.

As previously described, these characteristics of the pump-regulator assembly are determined by the interaction of the spool and sleeve. The pilot pressure generated by the load pressure of the system affects the spool.

where is flow coefficient of orifice, and represent the orifice areas, is discharge pressure of the hydraulic pump, and is density of working fluid.

The displacement of the control cylinder, in (4), is determined by the resultant force on the swash plate as shown in Figure 15. The various forces are expressed in the form of a complex nonlinear model. In this study, in order to derive more accurate results, the VDAPP was also implemented using AMESim software.

A VDAPP with a mechanical regulator system was established using AMESim simulation software, which allows a very accurate implementation of the response of a nonlinear system. In the field of hydraulic component design, AMESim is widely used to optimization and performance improvement as a review of the actual system [5]. Figure 16 shows an AMESim diagram for the analysis of the system performance of an MPR system that consists of nine pistons.

The maximum swivel angle was set to 16°, which is the same as in the real component, and the exclusion volume was set to 11.6 cm3/rev. All parameters of the VDAPP are the actual design values used in the experimental equipment. The experimental equipment was modeled by considering the nonlinear behavior of the MPR pump system.

If the pump is composed of an odd number of pistons, the number of discharging pistons is determined by the rotation angle of the piston, which located at regular intervals on the plate as follows [11]:

Figure 17 shows the simulation result when the pump is driven at 4500 rpm under no-load condition. The discharge flow rate is the sum of the flow rate of each piston. The pulsation in flow rate is observed in simulation result as shown in Figure 17. This simulation results also show that the average value of the discharge flow rate 49.8 L/min is less than the theoretical one 52 L/min because the internal leakage through the gap between the piston and cylinder block is considered in computer simulation.

Figure 19 shows the hydraulic circuit of test rig for VDAPP. The angular velocity of the electric motor is regulated as 4500 rpm, and the load pressure is adjusted by adjustable relief valve which installed in the discharge line of the VDAPP. The discharge pressure is slowly increased during 45 seconds. The load pressure, the discharge flow rate, and the angular velocity and the torque of the electric motor are acquired by data acquisition board in real time.

In this study, the constant power mechanical regulator system with variable displacement axial piston pump is considered. The constant power mechanical regulator with VDAPP has a problem of pulsation in the discharge flow rate at the cut-off area. In order to solve the problem, the internal behavior of the constant power regulator with VDAPP is analyzed by modeling the system using the AMESim software. The theoretical analysis of constant power regulator is induced for precise modeling, and the internal dynamics of un-measurable components are studied. The validation of the simulation model is confirmed by comparing the simulation results with the experimental output of the real system. By analyzing the dynamics of the unmeasurable internal components, it is found that the irregular discharge flow rate is caused by the discontinuous shape at the edge of the counterbalance piston. Therefore, we proposed the rounded shape for the edge of the counterbalance piston. The effect of the redesigned shape is implemented by AMESim simulation, and the validation is verified by computer simulation. The future work is experimental confirmation of the redesigned shape.

There are typically three types of hydraulic pump constructions found in mobile hydraulic applications. These include gear, piston, and vane; however, there are also clutch pumps, dump pumps, and pumps for refuse vehicles such as dry valve pumps and Muncie Power Products’ Live PakTM.

The hydraulic pump is the component of the hydraulic system that takes mechanical energy and converts it into fluid energy in the form of oil flow. This mechanical energy is taken from what is called the prime mover (a turning force) such as the power take-off or directly from the truck engine.

With each hydraulic pump, the pump will be of either a uni-rotational or bi-rotational design. As its name implies, a uni-rotational pump is designed to operate in one direction of shaft rotation. On the other hand, a bi-rotational pump has the ability to operate in either direction.

For truck-mounted hydraulic systems, the most common design in use is the gear pump. This design is characterized as having fewer moving parts, being easy to service, more tolerant of contamination than other designs and relatively inexpensive. Gear pumps are fixed displacement, also called positive displacement, pumps. This means the same volume of flow is produced with each rotation of the pump’s shaft. Gear pumps are rated in terms of the pump’s maximum pressure rating, cubic inch displacement and maximum input speed limitation.

Generally, gear pumps are used in open center hydraulic systems. Gear pumps trap oil in the areas between the teeth of the pump’s two gears and the body of the pump, transport it around the circumference of the gear cavity and then force it through the outlet port as the gears mesh. Behind the brass alloy thrust plates, or wear plates, a small amount of pressurized oil pushes the plates tightly against the gear ends to improve pump efficiency.

A cylinder block containing pistons that move in and out is housed within a piston pump. It’s the movement of these pistons that draw oil from the supply port and then force it through the outlet. The angle of the swash plate, which the slipper end of the piston rides against, determines the length of the piston’s stroke. While the swash plate remains stationary, the cylinder block, encompassing the pistons, rotates with the pump’s input shaft. The pump displacement is then determined by the total volume of the pump’s cylinders. Fixed and variable displacement designs are both available.

With a fixed displacement piston pump, the swash plate is nonadjustable. Its proportional output flow to input shaft speed is like that of a gear pump and like a gear pump, the fixed displacement piston pump is used within open center hydraulic systems.

As previously mentioned, piston pumps are also used within applications like snow and ice control where it may be desirable to vary system flow without varying engine speed. This is where the variable displacement piston pump comes into play – when the hydraulic flow requirements will vary based on operating conditions. Unlike the fixed displacement design, the swash plate is not fixed and its angle can be adjusted by a pressure signal from the directional valve via a compensator.

Vane pumps were, at one time, commonly used on utility vehicles such as aerial buckets and ladders. Today, the vane pump is not commonly found on these mobile (truck-mounted) hydraulic systems as gear pumps are more widely accepted and available.

Within a vane pump, as the input shaft rotates it causes oil to be picked up between the vanes of the pump which is then transported to the pump’s outlet side. This is similar to how gear pumps work, but there is one set of vanes – versus a pair of gears – on a rotating cartridge in the pump housing. As the area between the vanes decreases on the outlet side and increases on the inlet side of the pump, oil is drawn in through the supply port and expelled through the outlet as the vane cartridge rotates due to the change in area.

Input shaft rotates, causing oil to be picked up between the vanes of the pump which is then transported to pump outlet side as area between vanes decreases on outlet side and increases on inlet side to draw oil through supply port and expel though outlet as vane cartridge rotates

A clutch pump is a small displacement gear pump equipped with a belt-driven, electromagnetic clutch, much like that found on a car’s air conditioner compressor. It is engaged when the operator turns on a switch inside the truck cab. Clutch pumps are frequently used where a transmission power take-off aperture is not provided or is not easily accessible. Common applications include aerial bucket trucks, wreckers and hay spikes. As a general rule clutch pumps cannot be used where pump output flows are in excess of 15 GPM as the engine drive belt is subject to slipping under higher loads.

What separates this pump from the traditional gear pump is its built-in pressure relief assembly and an integral three-position, three-way directional control valve. The dump pump is unsuited for continuous-duty applications because of its narrow, internal paths and the subsequent likelihood of excessive heat generation.

Dump pumps are often direct mounted to the power take-off; however, it is vital that the direct-coupled pumps be rigidly supported with an installer-supplied bracket to the transmission case with the pump’s weight at 70 lbs. With a dump pump, either a two- or three-line installation must be selected (two-line and three-line refer to the number of hoses used to plumb the pump); however, a dump pump can easily be converted from a two- to three-line installation. This is accomplished by inserting an inexpensive sleeve into the pump’s inlet port and uncapping the return port.

Many dump bodies can function adequately with a two-line installation if not left operating too long in neutral. When left operating in neutral for too long however, the most common dump pump failure occurs due to high temperatures. To prevent this failure, a three-line installation can be selected – which also provides additional benefits.

Pumps for refuse equipment include both dry valve and Live Pak pumps. Both conserve fuel while in the OFF mode, but have the ability to provide full flow when work is required. While both have designs based on that of standard gear pumps, the dry valve and Like Pak pumps incorporate additional, special valving.

Primarily used on refuse equipment, dry valve pumps are large displacement, front crankshaft-driven pumps. The dry valve pump encompasses a plunger-type valve in the pump inlet port. This special plunger-type valve restricts flow in the OFF mode and allows full flow in the ON mode. As a result, the horsepower draw is lowered, which saves fuel when the hydraulic system is not in use.

In the closed position, the dry valve allows just enough oil to pass through to maintain lubrication of the pump. This oil is then returned to the reservoir through a bleed valve and small return line. A bleed valve that is fully functioning is critical to the life of this type of pump, as pump failure induced by cavitation will result if the bleed valve becomes clogged by contaminates. Muncie Power Products also offer a butterfly-style dry valve, which eliminates the bleed valve requirement and allows for improved system efficiency.

It’s important to note that with the dry valve, wear plates and shaft seals differ from standard gear pumps. Trying to fit a standard gear pump to a dry valve likely will result in premature pump failure.

Encompasses plunger-type valve in the pump inlet port restricting flow in OFF mode, but allows full flow in ON mode lowering horsepower draw to save fuel when not in use

Wear plates and shaft seals differ from standard gear pumps – trying to fit standard gear pump to dry valve likely will result in premature pump failure

Live Pak pumps are also primarily used on refuse equipment and are engine crankshaft driven; however, the inlet on a Live Pak pump is not outfitted with a shut-off valve. With a Live Pak pump, the outlet incorporates a flow limiting valve. This is called a Live Pak valve. The valve acts as an unloading valve in OFF mode and a flow limiting valve in the ON mode. As a result, the hydraulic system speed is limited to keep within safe operating parameters.

Outlet incorporates flow limiting valve called Live Pak valve – acts as an unloading valve in OFF mode and flow limiting valve in ON mode restricting hydraulic system speed to keep within safe operating parameters

In the parts tables below you may select the hydraulic parts you need. All PVplus parts we sell are genuine Parker Hannifin and originate in Germany. We highly recommend to use genuine OEM parts only to ensure smooth operation and longer service life.

The Parker PVplus hydraulic pumps are produced in Chemnitz, Germany and manufactured by Parker Hannifin Manufacturing Germany GmbH & Co. KG. The PV040R1K1T1WDC1 is an axial piston pump of variable displacement with a maximum displacement volume of 40.0 ml/rev. The mounting interface is according to metric (ISO 3019-2) and the pump control group is horsepower (torque) control. Further details are listed in the Parker PV040 Datasheet and pump control options.

All pump repair kits listed on this page are for Parker PVplus axial piston pumps of latest design series. Current design of Parker PVplus PV040 is 46 Design (hydraulic pump) and 45 Design (pump controller). The item numbers listed in these tables refer to the PV040 exploded view drawing of the Parker PV040 Spare Sparts List PVplus Design 46. Should you require spare parts for an older design PVplus pump, please contact us for further information (do not forget to include pump name plate information).

Be sure to operate the hydraulic pump under optimum oil viscosity (not too low) since a thinner lubrication film causes more direct metal to metal contact resulting in increased wear in glide and roller bearings. The PVplus bearing kit contains both the front and rear roller bearing of the drive shaft and are also included in the pump shaft repair kit. The PVplus trunnion bearing unit contains the two glide bearings of the pump swash plate (trunnion bearings are not included in swash plate kit).

Swashplate hydraulic pumps have a rotating cylinder containing pistons. A spring pushes the pistons against a stationary swash plate, which sits at an angle to the cylinder. The pistons suck in fluid during half a revolution and push fluid out during the other half. The greater the slant the further the pump pistons move and the more fluid they transfer.

Electro-Hydraulic Controls for Model (A)A4VSO (Sizes 40...1,000), Model A4VSH (Sizes 40...250), Model (A)A4VSG (Sizes 40...1000) and Model (A)A4CSG (Sizes 250...750) Swashplate pumps