ASTM D4378 In-Service Mineral Turbine Oils

ASTM D4378 is the practice for in-service monitoring of mineral turbine oils in steam, gas, and combined-cycle turbines used for power generation. It is a monitoring practice, not a test method. It tells a program which properties to watch, how to sample, and how to act when results drift — including the familiar conversation about remaining RPVOT relative to new oil.

Scope limits matter. D4378 is not the practice for auxiliary power-plant equipment oils — that is ASTM D6224. It is not a transformer-oil or DGA document. And it does not replace ASTM D2272: D2272 still supplies the oxidation induction time; D4378 is where that time is interpreted against the in-service program.

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ASTM Standard at a Glance

Related software

This practice is cited by VeroOCM.

Where this practice shows up at Vero

D4378 is the in-service mineral turbine-oil practice in the OCM standards library. It cites the test methods; it is not itself a fifteenth instrument.

See VeroOCM for the platform that applies that monitoring logic. For auxiliary plant oils use ASTM D6224 instead.