Sunday, October 25, 2009

Silicone grease

Silicone grease is a waterproof grease made by combining a silicone oil with a thickener. Most commonly, the silicone oil is polydimethylsiloxane and the thickener is amorphous fumed silica. Using this formulation, silicone grease is a translucent white viscous paste, with exact properties dependent on the type and proportion of the components.

Silicone grease is commonly used for lubricating and preserving rubber parts, such as O-rings. Additionally, silicone grease does not swell or soften the rubber, which can be a problem with hydrocarbon based greases. It functions well as a corrosion-inhibitor and lubricant for purposes that require a thicker lubricant, such as the operating mechanism of the M1 Garand rifle.

Thermal grease often consists of a silicone grease base, along with added thermally conductive fillers. It is used for heat transfer abilities, rather than friction reduction.

Silicone grease is also used widely by the plumbing industry in faucets and seals, as well as dental equipment. Electrical utilities use silicone grease to lube separable elbows on lines which must endure high temperatures. Silicone greases generally have a temperature range of -40 to 400 °C.