【 Weak current College 】 chillers "surge" is going on?

The "surge" should be a single-stage centrifugal compressors (i.e. speed type refrigeration compressor) are specific to a feature. It is manifested in when single-stage centrifugal compressor in low load (rated load of 25%), prone to "surge", causing periodically increased noise and vibration, serious or even damage to the compressor.
This may be single-stage centrifugal compressor special structure and operation of the decision, because it is a kind of speed type refrigeration compressor, not volume-refrigeration compressors (reciprocating and Rotary).
Centrifuge group surge as above mentioned several expert, is the property of single-stage centrifugal machine group, it is because the compressor discharge pressure was less than condenser pressure, causing the compressor could not achieve the exhaust, but the compressor and constantly breathe, thus generating a violent vibration and noise. generally speaking, the unit load in less than the Unit 30% of the total load that you receive a "surge"-mainly due to the unit operation caused the load is too low, generally speaking, the first is the overall system load is too low, and the use of centrifuges group must run may appear,
You can take measures, if you have already used the centrifuge group, can be set in the computer system to ensure that minimum working load units in more than 30% (this is the most stupid way)
The best solution is the system used by the unit size mix, that is, ensure that the entire system of minimum load is greater than the minimum of a centrifuge 30% load group or groups using centrifuge-and screw set and match programme
It is the inherent characteristics of centrifugal compressor, but with the speed change and surge point after the offset. Production is due to the compressor discharge pressure was less than condenser pressure, pressure surge of impact to the impeller. High-speed centrifuge is particularly easy to produce surge (such as Kalee, York of single-stage centrifugal), typically by hot gas bypass way to overcome, and the other is by limiting the opening of the guide vane to limit condensation pressure increases. For low-speed speed of multilevel centrifugal machine due to lower General 2900, surge point away from work, this model at run time you can in 10% of the running under low load (such as multi-level centrifuge tring)
Surge is a centrifuge-specific, but not just single-stage, multi-stage centrifugal machine so will gasp, Te 3 centrifuge does asthma? why is in low load less suction, discharge pressure is lower than the condensing pressure, causing gas reflux condenser. Characteristic is the sound great, current fluctuations.