Hydraulically Connecting The Axial Piston Unit - Bosch Rexroth 3 Series Instruction Manual

notices on routing lines

7.4.8 Hydraulically connecting the axial piston unit

Insufficient suction pressure!
Generally, a minimum permissible suction pressure at port S is specified for axial
piston pumps in all installation positions. If the pressure at port S drops below the
specified values, damage may occur which may lead to the axial piston pump being
damaged beyond repair.
▶ Make sure that the necessary suction pressure is not undercut. This is
influenced by:
– The piping (for example, suction cross-section, pipe diameter, length of
suction line)
– The position of the reservoir
– The viscosity of the hydraulic fluid
– A filter element or check valve in the suction line, if these are fitted (regularly
check the filter element's level of contamination)
The machine/system manufacturer is responsible for dimensioning the lines. The
axial piston unit must be connected to the rest of the hydraulic system in accordance
with the hydraulic circuit diagram of the machine/system manufacturer.
The ports and fastening threads are designed for the maximum permissible
pressures p , see Table 10 "Ports A4CSG series 1x and 3x" on page 39. The
max
machine/system manufacturer must ensure that the connecting elements and lines
correspond to the specified application conditions (pressure, flow, hydraulic fluid,
temperature) with the necessary safety factors.
Connect only hydraulic lines that are appropriate for the axial piston unit port
(pressure level, size, system of units).
Observe the following notices when routing the suction, pressure, and drain lines.
• Lines and hoses must be installed without pre-tension pressure, so that no further
mechanical forces are applied during operation that will reduce the service life of
the axial piston unit and, if applicable, the entire machine/system.
• Use suitable seals as sealing material.
• Suction line (pipe or hose)
– The suction line should be as short and straight as possible.
– Measure the line cross section of the suction line so that the pressure at the
suction port does not drop below the minimum permissible pressure. Make sure
that the maximum suction pressure is not exceeded (for example, when pre-
filling).
– Make sure the connections and connecting elements are airtight.
– The hose must be pressure-resistant, also regarding external air pressure.
• Pressure line
– For the pressure lines, use only pipes, hoses and connecting elements rated for
the working pressure range specified in the data sheet 92105 (see Table 10).
NOTICE
RE 92105-01-B/06.2017, A4CSG, Series 3x, Bosch Rexroth AG
Installation 37/68