Rexroth DB10 Pilot operated Pressure Adjustment Relief Valve
There are some troubleshooting below affected the valve   characteristics:
Failure of pressure ajustment and relief:the pilot valve  spool spring break,the throttle hole is block;poor seal of  oil port;the main spool stuck.
Trouble clearing measures:replace the broken parts for emergency use,clean,dredge,grinding or the oil circuit breaker for emergency use;grinding,cleaning.The corresponding trouble clearing measures:re-adjustment;correction,the padded or replace;replacement,cleaning.
pilot type relief pressure limiting instability for the gradual onset fault,pilot-type relief valve failure for the

sudden failure exclude failure after limited should the system pressure relief valve on the pilot control pressure  readjustment.