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Important Considerations for Selecting O-rings

From Apple Rubber Products, Inc.

In any sealing application, correct O-ring selection is the result of a number of design considerations including dimensions, chemical compatibility and the ability to resist pressure and temperature extremes. It is helpful to pay particular attention to some basic sealing concepts when selecting an O-ring for your application. These include:

Sealing Pressure - Sealing pressure is the force exerted by compression of the seal between the mating surfaces forming the gland itself and external forces (i.e. the fluid being sealed) transmitted through the seal. A physical barrier is formed when the force from compressing the seal and pressure applied by the fluid being sealed causes the seal to fill all leak paths.

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Products & Services
Dynamic Seals
Dynamic seals include oil seals, hydraulic and pneumatic seals, exclusion seals, labyrinth seals, bearing isolators, and piston rings. They create a barrier between moving and stationary surfaces in applications such as rotating shafts and pistons rings.  This is a general search form; more detailed search forms are available.
Back-up Rings
Back-up rings or anti-extrusion rings are washer-like devices used to prevent seals from extruding through gaps while under pressure. Seals are installed in the downstream side of the gland.
Mechanical Seals
Mechanical seals including mechanical face seals, bellows, gas seals, and cartridge seals.
Oil Seals and Grease Seals
Oil seals and grease seals have a flexible lip that rubs against a shaft or housing to prevent the leakage or ingress of fluids and dirt.
Butterfly Valves
Butterfly valves control flow through a circular disc or vane by turning the valve's pivot axis at right angles to the direction of flow in the pipe. They are normally used as throttling valves to control flow.
Product Announcements
Web Seal Inc. - O-Rings from Web Seal
O-rings provide reliable leak-free seals and simple installation. They are an ideal, cost-effective solution for many sealing situations. (read more)
A.W. Chesterton Company - High-Performance Mechanical Split Seal
Chesterton just raised the bar! Long recognized as world leader in split seal technology with the largest installed base globally, the 442 Split Seal pressure capability has been increased to 450 Psig... (read more)
Daemar Inc. - Molded O-Rings
The O-ring is a simple and versatile seal that can be used in thousands of applications. O-rings are manufactured in a wide variety of compounds to suit your every need. (read more)
TM Electronics, Inc. - RS-01 TME Radial Sealing Fixture
The RS-01 TME Radial Sealing Fixture contains a pneumatically operated clamp that provides either a sealed leak tight access to a tubular product or a sealed leak tight dead end to the product during... (read more)
Freudenberg-NOK Sealing Technologies Simrit - Plate Seals
Plate seals are hybrid seals designed to incorporate the best features of flat gaskets and O-rings, while eliminating the drawbacks associated with each of those sealing methods. Plate seals... (read more)
 
Topics of Interest

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