Two stage compressor

[AMXX]

Hi ;
Is it possible that one stage of a two throw , two stage reciprocating compressor run while the other one is stopped?
if yes, except the shaft failure , is there any other possible failure cases to have this scenario ?

 

[zeusfaber]

I saw one once that managed to throw a conrod without any of the debris getting mixed up with the crankshaft or punching out through the side of the crankcase (in fact, it actually disconnected all four pistons - the operators complained that it appeared slow to build pressure, while remarking that it was running much more smoothly and quietly than usual). Worth saying that this one was the exception - we went through a phase of breaking quite a lot of machines and in every other case, the damage was more obvious (with metal - though disturbingly little oil - distributed liberally around the compartment).

 

[AMXX]

Thanks Zeusfaver to share your experience.

 

[Steve Beck]

Hi, AMXX thanks for such a brilliant question

 

[dcasto]

Yes, you can pull the suction valves out of one head of the compressor. You know that the unit will be a single stage and subject to higher differential and high rod loads and high discharge pressures

 

[AMXX]

dcasto,

Thanks. This can be an arranged operation. My question was about failure of one stage of the compressor during running of the train.

 

[dcasto]

The compressor manufacturers even have dummy cylinders where the compressor may require just 3 throws so the 4th throw has a dummy weight to balance the forces on the unit. Since the weight will not change on the throw you "crippled" and crippled is an actual technical term here, there is almost a nonissue. The issues will come with lubrication of the pin and bushing, but with no forces, it isnt a real bad issue

https://journals.sagepub.com/doi/abs/10.1177/0954408915578055?journalCode=piea