Emerson Exchange 365

A compressor going into stall is like jumping off a cliff with a bungee cord. If the bungee cord has no losses to dampen the oscillation, we have something akin to surge. A 0.5% drop in efficiency can occur for each surge cycle. Several surge cycles can occur due to delays and lags in high temperature, thrust, and vibration shutdown systems. In some compressors the damage is so severe after multiple surge cycles that rotors and seals need to be replaced. The cost of process downtime can be significant particularly when a compressor feeds parallel trains of equipment. The restart of exothermic fluidized bed reactors in the petrochemical industry may be the most hazardous mode of operation. Read the full text.