The compresion fitting uses a nut to slide over a section of pipe, followed by a ferrule or an O-ring. This nut is tightened against another line or fitting, which in turn compresses the ferrule or O-ring to form a seal. Compresion fittings are most common in pipe applications and require easy sealing. Fittings are usually disposable, but many types of compresion fittings can be reused by replacing the ferrule or O-ring and retightening the nut.
Compresion fittings provide waterproof sealing fittings in drains and water pipes, fixtures or faucets. In many domestic and commercial real estate sinks, compression fittings are found to provide a watertight seal in drains and water pipe and fixture or faucet fittings. This fitting rarely requires manual tightening to achieve sealing, and can even be used when mixing pipe types such as stainless steel and copper or plastic. Compresion fittings rarely require pipe sealant or Teflon threads, a waterproof sealing tape. In rare cases, a fitting can be sealed by gently turning it with a wrench. It is usually used in narrow spaces, which will cause fire hazard during welding, and compresion fittings are easy to install.
