The reason for the surge is that the intake air volume is too small, and the airflow separation phenomenon will occur on the convex side of the blade. When the airflow phenomenon is serious, the compressor exhaust pressure is reduced. If the pipe network capacity is large and the pressure is high, the pipe network The pressure is greater than the exhaust pressure, which makes the displacement of the compressor more reduced, which exacerbates the phenomenon of gas separation. As a result of the chain reaction, the displacement of the compressor will be zero or even negative (countercurrent), but the pressure of the pipe network is not maintained. Varying, as the pipe network vents to the process equipment, its pressure is also decreasing. When it drops below the compressor exhaust pressure, the compressor will vent to the pipe network, causing the pipe network pressure to rise, if the pipe The net resistance line is unchanged, and it is still the curve a, and the above cycle is repeated repeatedly, forming a "surge" of the airflow.

It can be seen from the surge formation process that under the condition of a certain pressure, the compressor flow can be prevented from being too small, and the surge can be effectively avoided. The automatic vent valve is added on the process pipe network to automatically increase the air flow, which is reliable and stable. Accurate throat differential pressure, exhaust steam pressure and human wind temperature detecting components, the pressure piping should not be blocked. The compressor outlet is provided with a venting line and a venting valve. The main venting valve should have good regulation performance, and can be fully opened in an emergency, with a small leakage, and a manual operating mechanism and a manual locking mechanism. In order to reduce the energy waste caused by the venting, when the venting valve is vented, the opening should be as small as possible, and in order to avoid the "surge" of sudden and sudden escape, the venting valve should have the characteristics of quick opening and slow closing.