What is a pp compression fitting?
Generally, a pp compression fitting consists of an inner ring and outer nut, made either of brass and copper. The inner ring is known as a ferrule. This fitted over pipes to be joined and the outer nut slipped over it. The piping is then clamped together by tightening the nut so it presses against the ring creating a tight fitting that should be air tight and water tight seal. When larger pp compression fittings are required, there is usually a flange, rather than a single nut, with a ring of bolts each of which must be tightened evenly to ensure a proper and effective seal. In all cases, the nut should not be too loose or over tightened as this can compromise the fitting and cause leakage.