Common Gasket Terminology
Whether preventing precious oil from leaking out of the your valve cover or engine, to ensuring that coveted air stays inside your SCUBA tank, gaskets are essential in many aspects of the mechanical world. In order to have a better, more comprehensive understanding of gaskets and their many uses, it's important to understand the terminology associated with them. Below are several terms to be familiar with when shopping for gaskets.
Gasket - A gasket is a mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression. They can be made from everything from silicone, neoprene and cork, to metal and rubber. Two of the more common gaskets are known as a valve cover or head gaskets.
Double-acting Seals - Seal rings which seal in two directions, on the push and the pull stroke of a hydraulic or pneumatic cylinder.
O-Ring - O-ring seals are circular rings of various cross-sectional configurations installed in a gland to close off a passageway and prevent escape or loss of a fluid or gas.
Head Gasket - A head gasket is a gasket that sits between the engine block and cylinder head in an internal combustion engine. Its purpose is to seal the cylinders to ensure maximum compression and avoid leakage of coolant or engine oil into the cylinders.
Valve Cover Gasket - Also known as a rocker cover gasket, it helps seal the joint between the rocker cover and the rest of the engine.
Silicone Adhesive - Adhesives made from silicone polymers that have excellent high temperature resistance.
Neoprene - Neoprene is a synthetic rubber. Neoprene compounds are known for their resistance to oil, sunlight and the negative effects of the ozone.