The O-Ring

　　The humble O-ring is one of the simplest, yet most engineered, precise, and useful seal design ever developed and is one of the most common and important elements of machine design.

　　O-Rings are manufactured in metric and imperial sizes and come in a variety of designs. A number of various size specifications exist and care must be taken to ensure you are purchasing the correct size specification.

　　The reason that O-rings are commonly used in machine design is that they are inexpensive, easy to manufacture, reliable and have simple mounting requirements in both static and dynamic mounting applications.

　　Thomas Edison way back in 1882 used a round rubber ring as part of his light bulb patent. A Swede patented an O-ring on the 12 th May 1896. It was an inventor, Niels Christensen who perfected the O-rings while developing automobile brakes. He patented his O-ring in 1937, however there was no interest until the aircraft boom of World War II. Christensen sold his O-rings to the military after tests proved the simple, critical O-ring enabled a complex technology to advance.