Page 195 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

Reciprocating Gas Engines and Compressors 177

Figure 5.1. integral gas engine compressor.

Figure 5-1 is a photograph of an internal gas engine compressor. Fig-
ure 5-2 illustrates a unit with compressor cylinders connected to a frame.
An electric motor drives the crankshaft in the frame. This is known as a
“motor-driven” unit. The driver could also be a turbine or an engjne.
Regardless of the arrangement, the maintenance of any unit can best be
considered by dealing with the compressor and the power units sepa-
rately. Since compressors generally require more maintenance than en-
gines, we will discuss compressors first.

Compressor Cylinder Maintenance
The following malfunctions can occur in a compressor cylinder regard-
less of the gas pumped and whether or not it is double or single-acting,
large or small in diameter or used as one of the stages of a multi-stage
unit:

Exceeding allowable rod load.
Accelerated wear and scuffing.
- Piston to liner.
- Piston rings.
- Piston rod and packing.