Why a VALVE fails to completely unload pump. [FAULT 2]

Trouble in Hydraulic Unloader  Valve

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This is a series of trouble shooting technique  for the track machine working in Indian Railway.  When you study  this you able to rectify a fault of machine. If this is helpful for you than share with others. It may helps them. Thanks for sharing.

Now we study about "Hydraulic Unloader  Valve"

2) Fault :-  Fails to completely unload pump. 

Probable causes and Remidial action.

1.  Valve pressure setting too high. 
>> Set valve at proper pressure. 
2.  Valve  spool  binding  in body. 
>>  Clean the spool and oil in the tank. 
3.  Incorrect assembly. 
>>  Assemble as per proper drawing. 
4.  Nil   or  low   nitrogen pressure in the accumulator. 
>>   Check pressure and recharge the accumulator    ( 80 to 85 bar). 
5.  Punctured bladder. 
>>   Change the bladder. 

CAUSE OF LOW PRESSURE OR NO PRESSURE [FAULT 1]

Trouble in Hydraulic Unloader  Valve

You are on n4net and this is indian railway track machine trouble shooting technology with you.

This is a series of trouble shooting technique  for the track machine working in Indian Railway.  When you study  this you able to rectify a fault of machine. If this is helpful for you than share with others. It may helps them. Thanks for sharing.

Now we study about "Hydraulic Unloader  Valve"

1) Fault :-  Low or No pressure.  

Probable causes and Remidial action.

1. Orifice of main piston choked. 
>>  Clean the orifice. 
2.  Vent connection open to tank. 
>> Plug the vent connection. 
3. Safety valve  at  zero setting 
>>  Set  the safety valve at proper pressure. 
4.  Broken  or weak spring 
>>  Replace the spring. 
5.  Worn ball  or seat. 
>>  Replace. the ball  or seat.