Page 263 - Reciprocating Compressors Operation Maintenance
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248 Reciprocating Compressors: Operation and Maintenance
Other techniques may further enhance the remedial measures. For
example, tensile loads can be transferred by means of reinforcing steel to
locations deep in the foundation where good concrete still remains.
A severely oil-degraded foundation may be capped with a thick layer
of epoxy grout laced with reinforcing steel properly placed and bonded
deep in the foundation. This technique is similar to the technique used
when a dentist caps a weak tooth. If a weak material can be contained, its
strength may be maintained.
INVESTIGATING WHETHER REGROUTING is NECESSARY
Measurements and analysis will help determine if regrouting is need-
ed. Here is one proposed sequence.
1. Make precision laser profile readings of compressor base or main
bearing machined areas from permanent benchmarks and record for
comparison with future readings.
2. Take hot crankshaft web deflection readings of the compressor and
record for study and future comparison.
3. Check for proper compressor rod runout and record readings.
4. Check for proper foundation bolt material and proper torque values.
Make record of any broken bolts as well as torque value. Founda-
tion bolt material should be AISI 4140 (B-7) or comparable high
tensile strength steel.
5. Inspect main bearings and record clearances.
6. Make visual inspection of compressor movement at corners during
operation and note condition on outline diagram of compressor
foundation.
7. Make visual inspection of grout and concrete foundation and note
condition on outline diagram of compressor foundation.
8. Compare readings and conditions with previous records. Compare
crankshaft web deflections with manufacturer's suggested maxi-
mum permissible. Discuss essential corrective measures and devel-
op a schedule for implementing corrections.
EFFECTS OF POSTPONING REGROUTING
Postponing routine maintenance of operating equipment, particularly
when regrouting is needed, will usually result in the foundation failing.
