Reciprocating Compressor ROD Drop?
Reciprocating Compressor ROD Drop?
(OP)
Hi,
We got ROD drop alarm and compressor was changed over with stand by compressor, when compressor was unloaded to zero load, lot of fumes was observed by field operator and on opening of inspection window we found cross head shoes are broken.
My question is, if ROD drop alarm is there then piston ring must go and 2nd question is what is the relation with ROD drop and cross head shoe damage.
Please explain about this condition.
Thanks
108/15L
We got ROD drop alarm and compressor was changed over with stand by compressor, when compressor was unloaded to zero load, lot of fumes was observed by field operator and on opening of inspection window we found cross head shoes are broken.
My question is, if ROD drop alarm is there then piston ring must go and 2nd question is what is the relation with ROD drop and cross head shoe damage.
Please explain about this condition.
Thanks
108/15L





RE: Reciprocating Compressor ROD Drop?
When that happens lots of stuff gets damaged.
RE: Reciprocating Compressor ROD Drop?
RE: Reciprocating Compressor ROD Drop?
RE: Reciprocating Compressor ROD Drop?
Before we changed the compressor with standby, Lube oil DP start increasing and went upto 2.1barg in 40 minute, after 30 minute and then ROD drop alarm appread and once we changed the compressor lot of fumes generated in the cross head compratment.
One thing to be remember in this problem is, lube oil supply pressure remained constant even DP across the filter went hi 2.1 barg, normal DP is 0.35barg.
Hope you can explain more about this problem.
Thanks
10815L
RE: Reciprocating Compressor ROD Drop?
RE: Reciprocating Compressor ROD Drop?
Main oil pump is crankcase driven and auxiliary is centrifugal type.Therefore, we does not change the pump.
Filter was changed over but second filter DP was also increased within 10 minute of change over.
Thanks
10815L
RE: Reciprocating Compressor ROD Drop?
What is your maintenance record of the piston rod run-out on your last overhauling? How about your piston rod deflection? Are they within limits? How about your crosshead shoe clearances? Are they within design limits?
RE: Reciprocating Compressor ROD Drop?
Please correct the Lube oil pumps, our auxiliary lube oil pump also gear pump.sorry about my typing mistake.
Rod Drop alarm limit is -0.8mm.And fumes were generated at cross head side not in piston side.
Thanks
10815L
RE: Reciprocating Compressor ROD Drop?
RE: Reciprocating Compressor ROD Drop?
3. Piston Deflection
That's a new one to me.
What exactly are you talking about?
RE: Reciprocating Compressor ROD Drop?
RE: Reciprocating Compressor ROD Drop?
I'm operation guy and data you asked not in my access but I will try to get it from reliability department.
thanks
108/15l
RE: Reciprocating Compressor ROD Drop?