LUBRICATING OIL COMPOSITION FOR ROTATING GAS COMPRESSOR

摘要

PROBLEM TO BE SOLVED: To obtain the subject lubricating oil composition not causing filter clogging trouble due to sludge even when used for rotating gas compressor having extremely excellent mist separation system by compounding lubricating oil base oil with a specific additive. SOLUTION: This lubricating oil composition for rotating gas compressor has a mist separation system in which mist separating ability is <0.02 g/N expressed in terms of stray mist amount and consists essentially of a compound selected from (A) a metal-based cleaning agent (e.g. an alkaline earth metal sulfonate such as calcium salt of petroleum sulfonic acid, (B) an ash-free dispersant (e.g. a succinimide having a 40-400C alkyl group) and (C) a disperse type viscosity index improving agent (preferably a disperse type polymethacrylate having 5,000-100,000 weight average molecular weight). The essential component is preferably compounded in an amount of 0.05-5 wt.% based on total amount of the composition. A composition further excellent in clogging-preventing property is preferably obtained by compounding a compound selected from the components A and B with the component C.