How to install an Axial Piston Pump


There are various hydraulic pump types, in numerous designs and pressures for a variety of hydraulic applications. Among the types, you can find gear, screw, vane and piston pumps. HYDAC axial piston pumps for open circuits feature specific displacements from 10 cm³ / rotation to 560 cm³ / rotation.

This article addresses how we should install an axial piston pump within a hydraulic system.

Installation notes for HYDAC axial piston pumps – PPV 100S

The pump should be installed horizontally, with the case drain line initially rising above the level of the pump before continuing to the tank as shown in the diagram below. Do not connect the drain line to the suction line. The top drain port should always be used and the internal diameter of the drain line should be equal to or larger than the drain port to minimise pressure build-up in the pump case. The pressure in the pump case should not exceed 1 bar as shown in the diagram below. Peak pressure should never exceed 4 bar.


Installing the pump above the tank




  • The distance between suction and drain pipes must be 200 mm minimum.
  • Suction and drain pipes must be immersed at least 200 mm below the lowest oil level under operating conditions.
  • The distance between the oil surface and the centre of the shaft must not exceed 1m.
  • The oil in the pump case must be refilled if the pump has not been operated for one month or longer.
  • When installing a HYDAC pump, always ensure that the fluid in the pump is prevented from draining away during stoppages.


Installing the pump vertically

For applications requiring vertical installation (shaft at the top) please connect lines as shown in the diagram below.

The oil level in the tank should be higher than the pump mounting flange (see diagram 1 below). If the oil level in the tank is lower than the pump mounting flange, then the drain line should be installed as shown in diagram 2 below.

Once the pump is installed in the tank and immersed in the oil, the drain ports must be open to provide adequate lubrication to the internal components.

If the pump is installed outside the tank, there must be a separate drain line to the tank (diagram 3 below). If the drain line is higher than the oil level, fill the line with oil before commissioning.




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22 – 26 August

In this course, you will strip and re-assembly a pressure compensated axial piston pump, including an in-depth look at the internal components.
• Pressure compensation
• Remote control
• Load sensing control
• Power controlComponents discussed in detail include control of variable displacement pumps, industrial and mobile valves. This course also introduces engineering calculations for hydraulic system engineering. Half of this course is classroom based and half of it is hands-on with exercises on our hydraulic training rigs. This course is suitable for maintenance technicians, trades people, sales people and engineers.Click here to download the course brochure and see the full program. In order to enrol, call us on 1300 449 322.

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