Unloaders may be part of the suction valve assembly. Suction and discharge valve failures are the most common component failure in a reciprocating compressor. The suction valves permit flow into the cylinder but not back out, and discharge valves permit flow to exit the cylinder but not return back in. Reciprocating compressor valves are essentially check valves.
When the piston is moving toward the head of the cylinder it is compressing gas as well as putting it into the process. When the piston moves toward the cylinder head the gas is being compressed but when the piston is moving away from the head, suction is pulling gas into the cylinder.ĭouble acting compressor cylinders compress gas on both movements of the piston. Single acting reciprocating compressors compress gas only when the piston is moving in one direction. Some reciprocating compressors are “single acting” and some are “double acting”. Rider bands are wide ring shaped devices that support the piston in the cylinder and prevent the two from touching. The rings act like seals to keep gas from bypassing the piston. A piston with rings and rider bands, cross head, and piston rod, which moves back and forth with each rotation of the crankshaft.Reciprocating compressor components include: Check valves within the cylinder are used to control the flow of gas within the cylinder.
Reciprocating compressors (see Figure H) represent a class of gas compressors that raises the pressure of a gas by means of a tightly fitting reciprocating piston inside a cylindrical chamber, reducing volume from intake to discharge, in order to generate flow.