History of O-ring Development

O-rings, also known simply as O-rings, first appeared in the mid-19th century as sealing elements for steam engine cylinders. The first O-rings were made of cast iron. Later, O-rings made of natural rubber were used for drain pipe joints with excellent results. By 1940, nitrile rubber with good oil resistance and neoprene rubber with good cold and heat resistance were introduced, and O-rings made from these materials were widely used for sealing gas, oil, and most chemicals.