Page 141 - Reciprocating Compressors Operation Maintenance

Operation and Maintenance of Reciprocating Compressors 1 27

Types of Synthetic Lubricants

There are literally thousands of synthetic fluids and lubricants, most of
which are not commercial items. There are a few fluids that are used in
commercial quantities, some of which have given satisfactory service in
lubrication of compressors. These fluids include:

1. Phosphate esters, such as Firequel, Pydraul, Houghto-Safe, Shell
SFR, etc. These are fire-resistant lubricants that have given good
service in air compressors.
2. Polyalkylene glycols (Ucon Fluids). These are available in water
soluble and water insoluble formulations and when used as recom-
mended, in the proper viscosity grade, have given good service in
gas compressors. They are not fire resistant.
3. Fluorocarbons (Halo-carbon). These are mentioned because they are
completely fireproof. They are suitable for oxygen compressor
lubrication; however, they are very expensive.
4. Diesters and polyalpha-olefins (PAO). These are used most fre-
quently as compressor synthetic lubricants. They include, Synesstic
(Exxon), Androl (Tenneco), MOCOA, 1R SSR coolant (Tenneco),
Sullair 24KT (silicon based).

If a change is made to synthetic oil in a compressor that has been oper-
ating with petroleum oil, it will require extensive cleaning of the piping
system as well as the compressor cylinder and its components. The syn-
thetic will loosen and possibly wash off deposits left by the petroleum
oils. The unit should be shut down after a short run with synthetic oil for
this extensive cleaning.

REGULAR INSPECTION AND MAINTENANCE

Compressor installations should be inspected regularly at intervals that
will have to be determined by the severity of operating conditions. Neces-
sary maintenance work such as replacing worn or broken parts; installing
new packing; changing crankcase oil; cleaning the crankcase, the force-
feed lubricator and the air filter; and removing deposits from valves, dis-
charge passages, coolers, and water jackets should be carried out promptly.
Following an overhaul, the entire system should be thoroughly
inspected. Typical tasks should involve the following: