Reciprocating compressor valve issues
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After we shut down the machine, the inlet and outlet of the compressor are closed. What is the state of the intake valve and the exhaust valve during nitrogen purging? If it is in the closed state, why can gas enter through the intake valve and exit through the exhaust valve during displacement?
There should be separate inlet and outlet for nitrogen
The intake valve is open, and the exhaust valve is closed. The exhaust valve opens to release air under pressure difference.
When the unit is shut down, the air valves remain closed due to the force of the springs. When the inlet pressure is higher than that inside the cylinder, the inlet valve is pushed open and gas enters the compressor cylinder. The pressure inside the cylinder is higher than that in the exhaust pipe, so the gas pushes open the exhaust valve and enters the exhaust pipe.
Oh, oh oh. Thank you! I think I understand. Because there is no pressure behind the exhaust valve after shutdown, the nitrogen gas that has entered the cylinder pushes the exhaust valve open due to the pressure difference. Right?
The air valves of a compressor function like multiple sets of one-way check valves: they do not prevent air from entering, but only prevent air from flowing back out.
Shouldn’t the load be set to 100% after shutdown?