What damage can operating a reciprocating compressor without opening the intake valve cause to the compressor itself?
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What damage can operating a reciprocating compressor without opening the intake valve cause to the compressor itself?
Generally speaking, there is no significant impact in the short term； Prolonged use can cause negative pressure at the inlet, while the outlet temperature rises, leading to damage to the air valve.
It’s easy to deflate the pipes, and the air valves can get damaged, which is very dangerous
The pressure in the inlet section is almost 0; at this point, the intake valve hardly moves. No gas is drawn in during the intake phase, and no gas is expelled during the exhaust phase, so the exhaust valve also does not move. With only residual gas expanding and contracting repeatedly, how can the gas valve get damaged? How can the temperature be increased? Under normal conditions, the pressure inside the pipe is several atmospheres higher than the external pressure; even if the interior is a vacuum, the pressure there is still just one atmosphere. So how can the pipe hold such pressure? I’m also a bit confused about these issues, so I’ve listed them for everyone to discuss.
The closure of the inlet valve does not mean that there is no gas in the pipeline; as the piston moves back and forth, it continuously draws out gas, causing the pressure inside the pipeline to drop below atmospheric pressure and thus a vacuum to be created. If the machine is not stopped in time, the pipeline will collapse under this pressure. If flammable gas is used, and air gets in through the damaged flange gasket, an explosion is still possible. Because the gas flow rate is low, the frictional heat cannot be dissipated, so the cylinder temperature rises sharply. This can also cause damage to the inlet valve, leading to accidents such as cylinder collision.
The temperature will definitely rise, but it won’t cause the pipeline to collapse; the reason lies in the piston rings, support rings, and gas seals, which are the weak points； Personal opinions are for discussion only! Give it a try with which brother! Hahaha
Reply to 1# ぃ☆ Both lips ぃ: Instant overload, including the transmission mechanism and the drive unit
It depends on whether the compressor is under load. Under load, the gas valves, packing, and other vulnerable components are prone to damage; the temperature will rise, but the pipes will not collapse
In my opinion, when the inlet valve is closed and the compressor is running, if the sealing system of the piston rod is inadequate, oil can enter the cylinder under negative pressure (in the case of oil-free lubrication compressors), or air can enter the cylinder (which poses a safety risk if flammable gases are present in the cylinder). Additionally, when it isn’t possible to ensure complete sealing of all the gas valves, a small amount of gas remains in the cylinder during compression; this gas being compressed repeatedly prevents heat generated by friction between the cylinder walls and the piston rings from being dissipated, leading to increased wear on the piston rings.
Reply to 1# ぃ☆ Both lips ぃ: Generally, no problems occur, but over time the temperature rises due to the movement of gas molecules. Meanwhile, the thrust plate and piston rings tend to wear out more easily than usual
It is best to start a reciprocating compressor under no-load conditions. By no-load, it means that the inlet valve is closed, all stages of the circuit are open, and all vent valves are also open. After the motor has been running for ten minutes without any problems, one inlet valve at a time can be gradually opened, followed by the gradual closing of the vent valves and circuit valves. Once the pressure has increased, gas can be supplied stage by stage.