Tag Archives for Centrifugal Compressors

Gas Turbine Driven Centrifugal Compressors

While the majority of natural gas field and transmission compressors are reciprocating machines, a sizable minority are centrifugal compressors driven by gas turbines. Only on rare occasions can electric, steam or deisel oil drives compete with natural gas as compressor … Continue reading

27. January 2010 by Jack
Categories: Gas Turbine | Tags: , | Leave a comment

Centrifugal Compressors – Suction and Discharge Shutdown Valves and Discharge Check Valves

These devices are required to isolate the compressor for the same reasons they are required for reciprocating compressors. Discharge Check Valve (Each Stage) In reciprocating compressors the compressor valves themselves act as check valves, preventing backflow from high-pressure stages to … Continue reading

22. September 2009 by Jack
Categories: Centrifugal Compressors | Tags: | Leave a comment

Centrifugal Compressors – Slowdown Valve

Slowdown valves must be installed in centrifugal compressors for the same reasons as in reciprocating compressors. They must be designed with more care than those on reciprocating units, since centrifugal compressors have oil film seals where the shaft goes through … Continue reading

22. September 2009 by Jack
Categories: Centrifugal Compressors | Tags: | Leave a comment

Centrifugal Compressors – Speed Controller, Inlet Guide Vanes

Speed Controller A speed controller is needed in conjunction with the surge control system. A new head-capacity curve is established for each speed, as shown in Figure 10-14. Inlet Guide Vanes The performance curve can also be shifted to match … Continue reading

22. September 2009 by Jack
Categories: Centrifugal Compressors | Tags: | Leave a comment

Centrifugal Compressors – Flare Valve, Suction Pressure Throttle Valve

Flare Valve As suction pressure increases or discharge pressure decreases, the compressor head requirement will decrease and the flow rate will increase. A flare valve will avoid stonewalling or overranging driver horsepower. Suction Pressure Throttle Valve A throttling device can … Continue reading

22. September 2009 by Jack
Categories: Centrifugal Compressors | Tags: | Leave a comment

Centrifugal Compressors – Recycle (Surge Control) Valve

A recycle valve is needed for surge control as well as for the conditions listed above for reciprocating compressors. At constant speed the head-capacity relationship will vary in accordance with the performance curve. For a constant compressor speed: • If … Continue reading

22. September 2009 by Jack
Categories: Centrifugal Compressors | Tags: | 1 comment

Centrifugal Compressors – Surge Control and StoneWalling

Surge is the most important process design consideration for centrifugal compressors. The surge condition occurs when the compressor does not have enough flow to produce sufficient head. At this point, the gas in the discharge piping flows back into the … Continue reading

22. September 2009 by Jack
Categories: Centrifugal Compressors | Tags: | Leave a comment