Compressor machines are used to increase the pressure of a gas by mechanically reducing its volume within its case. Air is most frequently compressed, but natural gas, oxygen and nitrogen are also compressed. Positive displacement, centrifugal and axial compressors are the three common types used in process facilities and pipeline stations.

Centrifugal and reciprocating compressors and their drives require a variety of auxiliary equipment to support operation.

Lube Oil consoles provide lubricating oil to the compressor bearings. These may be stand alone or be mounted directly on the compressor frame.

Seal oil consoles provide oil to the hydraulic seals located at the outer end of the compressor shaft.

Surface condensers reduce gas or vapor to a liquid by removing the heat.

Condensate pump removes the condensate from the hot well in the surface condenser.

Air blowers deliver fresh air to cool the internally housed electric motors.

Inlet air filters provide clean filtered air for operation of gas turbines.

Waste Heat system take hot exhaust gas from gas turbines and put high outlet temperatures like 400 to 650 deg C to use in various ways.

Compressor suction drum/knockout pot are provided since compressors require dry gas that is free of foreign particles.

Pulsation dampener/volume bottles minimizes the negative effects of vibration on the life of reciprocating compressors and associated piping.

Types of compressor drives are

A) Electric motor

B) Steam Turbine

C) Gas Turbine

General Compressor layout

Inlet Piping: The ASME power test code requires a minimum of three diameters of straight run piping between the elbow and the inlet nozzle. The preferred design is one in which the horizontal run is parallel to the compressor shaft.

Suction Line Strainers: Compressor suction lines must be free of any foreign particles that could damage the internals of the machine. Strainers are installed in the inlet line between the block valve and the compressor inlet nozzle.

Breakout flanges: All lines to a compressor that must be removed for maintenance of the compressor or strainer removal must have a set of flanges in the line in addition to the set at the compressor nozzle.

Miscellaneous Piping Connections should be piped up by one or the other.

Primary Operating Valve Accessibility for the operator from grade or the operating platform around the machine. Valves that are physically out of reach may be made accessible through extension stems or chain operators.

High pressure steam inlet piping on the basis of the compressor outline drawing to locate the neutral axis. Locating the line anchor close to the steel frame enable the designer to generate a layout with a minimum amount of leg, thereby satisfying the stress and flexibility requirements.

Straightening Vanes are provided to smoothen the flow and improve the compressor performance. These vanes must be in ASME or American Gas Association standards.

Reciprocating Compressor Piping should be simple and run as low to grade as possible to facilitate support. Once the piping is completed, it is simulated by electric circuits which identifies potential acoustic or pulsation problems.

Line branches should be located as close to line support as possible. All such connections should be located on top of the piping to minimize any potential liquid carry over.

Drain Piping should be provided on suction and discharge piping to avoid liquid carry over into the cylinders.