Gasket is a mechanical seal between two objects. It is usually used to prevent pressure, corrosion, and natural expansion and contraction between two objects. Since the machined surface cannot be perfect, irregularities can be filled by using shims. Gaskets are usually made of sheet materials such as pad paper, rubber, silicone rubber, metal, cork, felt, neoprene, nitrile rubber, fiberglass or plastic polymers (such as polytetrafluoroethylene). Gaskets for specific applications may contain asbestos.
A washer (washer) is a hole (usually in the middle) of a thin plate (usually round) that is usually used for distributing load thread fasteners. Other uses are as spacers, springs (Bellville gaskets, wave gaskets), wear-resistant gaskets, pre-display devices, lock devices. Rubber gaskets are also used in faucets (valves) to shut off flowing liquids or gases. Rubber or silicon gaskets can also be used to reduce fan vibration. Usually the outer diameter of the gasket is about twice the inner diameter
