Page 145 - Reciprocating Compressors Operation Maintenance

Operation and Maintenance of Reciprocating Compressors 131

plug all connections on these components. Keep low-point drain
valve on water side slightly open and wire valve in this position
(water side need only be flushed and air dried).
9, Fill all lubricators, lube pumps, and filter on compressor frame
with an approved preservative oil. Plug all connections and vents.
10. Coat flywheel with protective grease and cover with guard.
11. Coat all exposed shafts and linkages with protective grease. Cover
crankshaft opening from compressor with tape.
12. Remove all gear type couplings (hubs, spacers, keys) and disc-pack
of non-lube type couplings. Coat with an approved protective
medium and store in warehouse.
13. Protect all instrumentation and control panels according to appro-
priate procedures.

In a reciprocating compressor cylinder, the valves, without a doubt,
have the greatest effect on the operating performance of the machine,
both from an efficiency standpoint and from a mechanical reliability
standpoint.
The valves are installed in the compressor cylinder directly in the air
or gas stream, and are subjected to considerable abuse. It is surprising
that we generally have as little valve trouble as we do.
Stop and consider for a moment just what is expected of a compressor
valve. It must open and close with every stroke of the piston, many times
each minute. The number of times each valve operates in eight hours, a day,
a week, and a year at different compressor speeds is shown in Table 3-3.

TABLE 3-3

VALVE ACTUATIONS PER TIME UNIT WITH VARIABLE COMPR ESSOR SPEED
Compressor sp**d, rpm
Time 300 600 1000
8 HOURS 144,000 288,000 480,000
24 HOURS 432,000 864,000 1,440,000
1 WEEK 3,024.000 6,048,000 10,080,000
1 MONTH (30 DAYS) 12,960,000 25.920.000 43.200,000
1 YEAR (365 DAYS) 167,680,000 315,360,000 525,600,000