Bosch rexroth A21VG 10 Series Instruction Manual page 35

Risk of mix-ups with
threaded connections
• Drain line
– Always route the reservoir lines so that the case is constantly filled with
hydraulic fluid and to ensure that no air gets through the shaft seal even during
extended standstill periods.
– The case pressure must not exceed the limit values listed for the axial piston
unit in the data sheet under any operating conditions.
– The reservoir line joint in the reservoir must always be below the minimum fluid
level under all conditions (see chapter 7.3 "Installation position" on page 27).
• If the axial piston unit is equipped with installed screw fittings, these must not
be unscrewed. Screw the threaded plug of the fitting directly into the installed
screw fitting.
Axial piston units are employed in regions using the metric measuring system, in
regions using the Anglo-American (imperial) measuring system and in regions using
the Japanese measuring system (JIS – Japan Industrial Standard). Moreover,
various kinds of seal are used. The system of units, the kind of seal, and the size of
female thread and threaded plugs (e.g. locking screw) must all match. Due to the
limited options for visually detecting differences, there is a risk of mix-ups.
WARNING! Leaky or popped-out threaded plugs!
If a threaded plug which is of a different measurement system, kind of seal and
size with respect to the female thread is pressurized, the threaded plug may loosen
itself or even be ejected from the hole in a projectile-like manner. This can result
in serious injury and damage to equipment. Hydraulic fluid can be discharged from
this leakage point.
▶ Use the drawings (installation drawing) to determine the required threaded
plug for each fitting.
▶ Make certain that there are no mix-ups when installing fittings, mounting bolts
and threaded plugs.
▶ For all female threads, use a threaded plug from the same system of units and
of the correct size.
RE 93223-01-B/09.2020, A21VG Series 10, Bosch Rexroth Corporation
Installation 35/56