Rubber O Ring

An O Ring is a circular or doughnut shaped rubber ring which is used as a mechanical seal or gasket. O Rings are made from elastomeric compounds such as natural or synthetic rubber. The rubber o rings are widely used in industrial applications. There can be o ring seals, o ring gaskets used for various purposes. The basic purpose of o rings is to seal mechanical parts against air or liquid or any fluid movement. It is a loop of elastomer with a round or o-shaped cross-section which can be used as a mechanical seal. O Rings are designed to be seated in a groove and compressed between two or more parts during assembly thereby creating a seal at the interface. O Rings can be used in two ways: in valves as a face seal and rotating shafts on the inside. One of the most common seals used in machine design is o rings because they are inexpensive. They are easy to make, reliable, and have simple mounting requirements. It is stated that O ring has the capacity to seal tens of mega pascals (thousands of psi) pressure.

Buying Tips for O Rings
The ring selection depends on

• Chemical compatibility
• Sealing pressure
• Lubrication needs
• Sizes
• Cost
• Specifications of O Rings
  • Inner Diameter
  • Outer Diameter
  • Operating Temperature

Types of Rubber used in making O Rings

• Nitrile O Ring
• Silicone O Ring
• Viton O Ring
• Ethylene Propylene
• Neoprene O Ring
• Polyurethane O Ring etc.

How does an O Ring works?

By joining metal surfaces, the O-Ring works as a seal through the mechanical twist of the electrometric composite. The pressure which moves the ring is derived by the mechanical pressure, squeezing of proper gland design, the selection of the material, and by the system pressure sent in by the liquid itself. The ring does the sealing through the deformation of the seal material by installation and media pressure, thereby closing the gap between mating components. However, high pressures can cause deformation through the gap, known as extrusion, which results in seal failure.

Types of Rubber O-Rings
There are two types of O-Rings: Static O Ring and Dynamic O Ring. Static Seal is the one which does not move, except for pulsation caused by cycle pressure. Dynamic seals are those seals that are subjected to movement. O-rings are successfully used in both static and dynamic applications.

Advantages

• Cost effective
• Reliable
• Easy to make
• Easy to install
• Used in wide variety of applications, both static and dynamic

Applications
The applications of O Rings can be categorized into two groups:

• Static Applications
  • The cross section of the ring is squeezed axially in the groove which is similar to a flat gasket.
  • The cross section of the ring is squeezed radially in the groove, between the inside (ID) and outside (OD).
  • It is also axially squeezed in a dovetail groove.
  • It is used for sealing straight thread tube fittings.
• Dynamic Applications
  The seals or rings are used in applications that slide back and forth. This motion introduces friction that leads to creating designs different from those of static seals. Dynamic applications of O Rings are seen in both rotary and reciprocating movement. These rings are used in a variety of other applications such as wipers, buffers, and drive belts.