hi to all.
What maybe the cause of an air compressor which has high discharge pressure on first stage but normal on the second stage.?
If anyone has an idea. please do comment and share your knowledge. Thank you so much
Assuming this is a 2 stage machine, I'd look at 1st stage discharge valve, 2nd stage suction valve and checking the intervening cooler for blockage.
The fact that the final stage discharge is normal can be a bit misleading as it's usually determined more by what's going on downstream (eg PMV settings) than by the product of final stage suction pressure and potential compression ratio.
I have always found high interstate pressure to be caused by a leaking second stage suction valve or high interstate temperatures caused by an ineffective intercooler.
Following the elimination process, start with second stage inlet valve which is most likely. If that is not true then look for temperature rise and any blockages. First of all make sure that the pressure gauge is giving true readings./Cheers