Page 173 - Reciprocating Compressors Operation Maintenance

Operation and Maintenance of Reciprocating Compressors 1 59

Note: Face Cylinder Outer Head and Read Clockwise
I.B. Inboard End S. Suction Side
O.B. Outboard End D. Discharge Side
FIGURE 3-2O. Typical valve location chart showing a common valve number-
ing system (Source: Dresser-Rand, Painted Post, New York).

When a valve has to be changed, it should be removed and tagged with
identifying marks, as shown in Figure 3-20. For example, 1st stage, IB,
2D refers to first stage frame end, center discharge. A properly recondi-
tioned replacement valve should now be installed. The valve that was
removed should then be examined and a record made, identifying the
failed part and its location. Figure 3-21 shows the type of valve record or
report which should be maintained.

DISASSEMBLY, ASSEMBLY, AND INSPECTION PROCEDURES

Disassembly

Refer to Figure 3-22A for a typical valve assembly with conventional
restraint.

1. Remove valve screw cap and back off valve jam screw a minimum
of four complete turns.
2. Remove valve cover nuts and remove valve cover.
3. Loosen set screws holding valve yoke and remove yoke.
4. Remove cover and valve seat gaskets and discard.
5. Carefully clean gasket seating surfaces on valve covers and valve seats.
6. Visually inspect valve seats for any signs of damage such as burring,
wire drawing, and breakage.