Anti-surge flow rate of rich gas compressor

This post was last edited by CHANGBAISHI on 2017-7-15 at 15:42. Firstly, there are two types of surge in centrifugal compressors; one is caused by an insufficient amount of air being drawn in, and this type produces a low-level noise. It mostly occurs during startup at the lowest load, as a result of the intake valve opening too little ； Another cause is the commonly seen issue of excessive outlet pressure; when the pressure of this airflow exceeds the centrifugal force generated by the impeller, backflow occurs. Based on the characteristics of gas elasticity, normal operation is restored when the outlet pressure is lower than the centrifugal force pressure generated by the impeller. This periodically occurring phenomenon is known as surge. “What is the difference between the compressor surge flow rate and the anti-surge flow rate? ”This may be called differently depending on your industry. It is usually the relationship between pressure and flow rate; each centrifugal compressor has a characteristic curve, with a certain pressure corresponding to a certain flow rate. When the set pressure is constant, and the flow rate is below a certain value such that the centrifugal force generated by the impeller equals or is less than the compressor outlet pressure, this flow rate is referred to as the \"choking flow rate\" As for the explanation of “stall prevention flow rate,” that might be one thing, right? For reference. In actual operation, pressure increases mostly due to user factors that result in a reduction in gas consumption. The most effective approach at this time is to keep the compressor outlet pressure at the normal set value. There is usually an anti-surge venting automatic control system. The early model is controlled by a manual relief valve. Another factor is the surge caused by low grid voltage. The handling method is the same, but the set pressure needs to be lowered. The sound before surge can be predicted; if the pressure increase is rapid, surge is very likely to occur. After surge occurs, there is a periodic roaring sound, along with significant fluctuations in current and flow rate – these are the phenomena observed. These data should be measured when the equipment is put into trial operation, and used as parameters for future operation control. Remember, be sure to keep the outlet pressure below the surge zone. It is recommended to use export pressure as a reference point for control: release vapor when the pressure is high, and reduce it when the pressure is low. It’s just a means of adjustment. The adjustment of the air delivery volume in centrifugal air compressors is divided into speed regulation (variable frequency) ； Rear output valve adjustment (prone to overpressure) ； Adjustment of the intake valve in front of the engine (prone to surging) ； Using air conditioning behind the machine is a common approach.