O-rings seals

           When choosing an “O”-ring there are several factors to consider in determining proper selection including: the application for which the “O”-ring is to be used; the media to be sealed; the size of the fastener to be sealed; and the temperature and pressure to which the “O” ring will be subjected. Once each of these factors has been considered and an “O” ring has been chosen, engineering calculations should either be checked manually or by using “O” ring selection software. videozoom Download the Flash plug-in When choosing an “O”-ring there are several factors to consider in determining proper selection including: the application for which the “O”-ring is to be used; the media to be sealed; the size of the fastener to be sealed; and the temperature and pressure to which the “O” ring will be subjected. Once each of these factors has been considered and an “O” ring has been chosen, engineering calculations should either be checked manually or by using “O” ring selection software.         

This article is about is about the mechanical seal. For other uses, see Oring.

Typical O-ring and applicationAn O-ring, also known as a packing, or a toric joint, is a mechanical gasket in the shape of a torus; it is a loop of elastomer with a disc-shaped cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, creating a seal at the interface.

The O-ring may be used in static applications or in dynamic applications where there is relative motion between the parts and the O-ring. Dynamic examples include rotating pump shafts and hydraulic cylinder pistons.

O-rings are one of the most common seals used in machine design because they are inexpensive, easy to make, reliable, and have simple mounting requirements. They can seal tens of megapascals (thousands of psi) pressure.