Glandless Piston Valve

FM PISTON VALVE is a zero leak isolation Piston Valve, in which the seat & gland are replaced by Lower & Upper Sealing rings along with a Piston. This overcomes the difficulties usually associated with the replacement of conventional seats.
The FM Piston valve is the name for prevention of inline leakage as well as leakage through glands, making for leakproof isolation in the pipelines.
The FM Piston valve is a seat less & gland less Piston Valve. At the heart of the FM piston valve are Piston & sealing rings. A burnished piston seals against SS reinforced graphite rings to achieve a leak proof shutoff. This unique design ensures a long life even at high temperatures up to 427 deg C
A Burnished piston is connected to the Piston Valve stem & hand wheel. The piston passes through two sealing rings separated by a lantern bush. Each sealing ring is Stainless steel reinforced graphite, which has both features of sustaining compression exerted by Bonnet & providing soft seal against piston. The upper sealing ring acts as a conventional gland packing and prevents leakage towards atmosphere. The lower sealing ring acts as the seat which prevents in line leakage. The lantern bush is required to maintain separation between the upper & lower rings & to allow flow through the Piston Valve.