Page 78 - Reciprocating Compressors Operation Maintenance

Design and Materials for Reciprocating Compressor Components 65

Normal Force Due to
Gas Pressure
Cylinder Side
Gas Pressure m -** fmvn ^
Pist. Rod Packing Ring
Friction Force Due To
Reciprocating Motion of
Piston Rod
Piston Rod

FIGURE 2-25. Friction forces acting on compressor piston rod.

CROSSHEAO-j CROSSHCAD

OIL HEAD

OIL SCRAPCM MNOS

•CHAPEM MN6

HOUSING

FIGURE 2-26. Screwed piston rod—crosshead connection (Source: Dresser-
Rand, Painted Post, New York).

Piston Rod to Crosshead Connections

The piston rod is always screwed into the crosshead and locked with a
nut except in the case of the floating coupling arrangement to be
described. This discussion will concern only the arrangement which is
screwed into the crosshead. Refer to Figure 2-26 for a section through
the crosshead frame.