In order to prevent the gas in the cylinder from leaking from the piston rod, a set of packing is set in the cylinder seat, among which the lower part of the first and second stage cylinders is equipped with low-pressure packing parts, and the third stage cylinders are installed with high-pressure packing parts, which are composed of packing box, oil scraper ring, sealing ring, etc.
Crosshead assembly is composed of crosshead slide guide and crosshead. It is made of nodular cast iron. The crosshead receives oil from the crankcase through the oil distributor. The crosshead pin and the small head of the connecting rod form a movable joint of the crosshead, and obtain pressure lubrication through the oil circuit in the connecting rod. The packing box on the piston rod separates the crosshead assembly from the compression chamber. The seal on the piston rod can be adjusted by itself
The crosshead is the part connecting the connecting rod and the reciprocating piston rod. It has the guiding function and bears the lateral force of the compressor. The crosshead of this machine is made of nodular cast iron, on which there are threads for connecting piston rod and crosshead pin for connecting rod.
During assembly, the notches between the piston rings are staggered. In addition, the internal thread of the lock nut used for connecting the piston and the external thread of the piston rod at the joint and the internal thread of the piston rod at the joint need to be coated with loctite 640 glue to prevent loosening.