48/56 Troubleshooting
Bosch Rexroth AG, DBA...1X/...E, RE 25880-B/10.18
Fault
Possible cause
Remedy
Safety valve is
permanently flown
through.
A safety valve with unsuitable
response pressure has been
installed.
Check the specified response pressure
of the safety valve by means of the last
figure of the component marking at
the safety valve or name plate. Select
and order a safety valve with suitable
response pressure.
The difference between
operating pressure and
response pressure of the safety
valve is too small.
Check whether the system can be
operated at lower operating pressure
or select and order a safety valve with
suitable response pressure.
Dirt prevents the closing of the
safety valve.
Establish oil cleanliness by means of
suitable measures.
Type
DBA...1../...E
: Flush the safety
valve; to do so, unload the safety valve
at the adjustment device,
see chap. 10.2.4.
Type
DBA...2../...E
: Make the safety
valve respond on a separate, suitable
test stand in order to flush the dirt
out of the gap between valve seat
and poppet. If you are not successful,
replace the safety valve.
Safety valve
oscillates.
Together with other
components, the safety valve
constitutes an oscillating
system in which there are
regulating oscillations.
A safety valve may not be used as a
high-response valve.
Sealing is damaged
or missing.
The lead seal has been
destroyed by the operating
personnel or mechanical
influence.
The safety valve may not be re-sealed
or repaired. Otherwise the approval
according to PED will no longer apply.
Replace the safety valve.
External leakage
(leakage at the pilot
control valve or at the
main stage)
The seal of the adjustment
device is worn.
Replace the safety valve.
Plug screw at Y port is leaking;
seal ring at the plug screw is
worn.
Replace seal ring; make sure the
sealing surface is intact. Screw-in
the plug screw and tighten it using
the specified tightening torque,
see
"Data sheet 25880"
.
The valve is leaking between
the housing and the pump,
the housing and the flange
connection or at the tank
port. The R-ring in the housing
connection surface is worn,
see
"Data sheet 25880".
Replace seal kit or R-rings. Screw-in
the valve mounting screws and tighten
them using the specified tightening
torque, see also 7.7 "Assembly of the
safety valve".