A premium R&O or lightly AW circulating oil, usually ISO VG 32 or 46, designed to last many years in a turbine reservoir. It must shed water fast, release entrained air, resist foaming and hold off oxidation, which labs track with RPVOT and MPC. Gas turbines run their oil hot on Group II and III base stocks, and their main failure mode is varnish rather than the sludge typical of steam units.
Turbine oil's eleven years in and RPVOT is still at 60 percent of new, we're keeping it.
Also heard as
- R&O turbine oil
Related terms
R&O
Rust and oxidation inhibited: a lightly additized oil with no antiwear or EP chemistry.
RPVOT
Rotating pressure vessel oxidation test, which rates how much oxidation life is left in an oil.
Varnish
Thin, sticky, amber-to-brown deposit from degraded oil that coats valves, bearings and coolers.
Demulsibility
How quickly an oil sheds water and settles into clean layers after being churned with it.
MPC
Membrane patch colorimetry, a test that measures varnish-forming material in turbine and hydraulic oils.