How much can the capacity of a six-cylinder reciprocating compressor be reduced by unloading?

The capacity of a six-cylinder reciprocating compressor can be reduced by unloading by approximately one-third, which is represented in the answer choice of 33-1/3%. Unloading refers to the method used to control the output of a compressor without completely shutting it off. This is achieved by diverting some of the discharge from the compressors or by adjusting the timing of the intake valves.

In the case of a six-cylinder reciprocating compressor, typically, unloading is designed to allow a reduction in capacity by effectively allowing some of the cylinders to remain inactive during certain periods of operation. Since there are six cylinders, unloading typically results in fewer cylinders operating at a given time, with a common ratio being that one-third of the cylinders can be unloaded without severely impacting overall functionality.

This means that when implemented, the reduction could reach around 33-1/3%, making it a common and efficient adjustment for managing compressor loads under varying operational demands. This is an important operational understanding for anyone involved in commercial air management, as it influences performance and energy consumption.