What is compressor surge?
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What is compressor surge, and how can one quickly determine whether surge is occurring indoors or outdoors?
During operation, as the flow rate of the compressor continues to decrease and reaches its minimum value, severe rotational separation occurs within the compressor’s flow channels, causing the outlet pressure to drop suddenly. The pressure in the outlet piping system also drops, which results in gas from the piping system flowing back into the compressor.
Inside the facility, when surge occurs in the monitoring footage, there are significant fluctuations in outlet pressure and flow rate; at the same time, a loud surging sound can be heard on site, which is periodic in nature and not the continuous, steady sound associated with normal operation. Once surge occurs, the backflow valve should be opened immediately
The pressure difference between the compressor outlet and the throat decreases
Surge occurs when the amount of air drawn in decreases to a certain level, causing the anti-surge valves built into the compressor to open fully in order to ensure its safety. Outside, it is possible to hear the sound of the unit becoming louder and sharper – this is essentially a sign of surge
Surge occurs when the inlet pressure of the compressor is low, or in other words, when the amount of air drawn in is low. Every compressor has a minimum amount of air required for operation; if this amount is not met, a valve located on the anti-surge line opens, allowing air to flow back from the outlet
Surge is a type of abnormal vibration that occurs in vane compressors when the flow rate decreases to a certain level. A centrifugal compressor is a type of turbine compressor, and surge poses a serious threat to centrifugal compressors. When a centrifugal compressor experiences surge, typical phenomena include: 1) The outlet pressure of the compressor first rises, then drops sharply, exhibiting periodic and significant fluctuations ； 2) The compressor’s flow rate drops sharply and fluctuates significantly; in severe cases, air even flows back into the suction pipeline ； 3) The current and power meter readings of the compressor motor become unstable, with significant fluctuations ； 4) The machine experiences severe vibration, along with abnormal airflow noise. Currently, there are three common methods to address surge: ① Adding bleed valves to the compressor to allow excess gas to be discharged. ②Use a twin-rotor or triple-rotor compressor. ③Use adjustable blades.
It’s just like having asthma – one can’t catch their breath