Page 285 - Reciprocating Compressors Operation Maintenance

2E7O Reciprocating Compressors: Operation and Maintenance

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FIGURE 4-22. Unacceptable ring groove configurations.

developed, grooves should be trued up in a lathe, and rings of greater
width installed. The dashed line "N" illustrates how grooves should be
remachined to their full depth.

Piston Ring Groove Depth

The groove depth must be slightly greater than the radial thickness of
the ring. One easy way of checking this is to put the ring in the groove
and use a straight edge as shown in Figure 4-23.

Clearance _ *• Straight Edge
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12m

FIGURE 4-23. Groove depth must exceed radial thickness of ring.

Each ring should be tried in the groove it is to occupy and rolled com-
pletely around to make sure there is no obstruction in the bottom of the
groove at any point. The ring should move freely without sticking.
Rings used in conjunction with rider rings on the piston should be
checked as shown in Figure 4-24 to assure they do not protrude beyond
the rider.