Piston Valve is a linear movement valve in which a stainless steel piston travels between the upper and lower seal ring. These rings are separated by a lantern bushing, which supports the piston and creates a tight seal. When the valve is in the open position, the upper seal ring, in conjunction with the piston, prevents leakage through the stem. In the closed position, the lower seal ring seals the valve passage and provides a tight shutoff.
Advantages of Piston Valves
- High Return on Investment across full service life compared to Globe Valves.
- Excellent control statistics.
- Long time Maintenance Free, no wear on sealing surfaces.
- Exceptional leak tightness across the ports and to atmosphere.
- Insensitive to impurities due to maintenance free sealing system.
- Environmentally safe and energy efficient.
- Valve rings are replaceable in the line.
- Extraordinary sealing system amazingly simple and reliably tight.
Design Features of Piston Valve
Valve designed as straight-through piston valve, pressure-relieved. In line and stem sealing by two flexible valve ring made from special material, Body made of Cast steel / Stainless steel, Bonnet made of Cast steel / Stainless steel, Hand wheel made of grey cast iron/Cast steel, and Piston Consisting of corrosion resistant steel.
The valve rings are made of specially material. They have no asbestos containing materials and make the valve maintenance free. “Install and Forget” is the motto. The coupling pressure on the piston is so high that media are reliable checked up to 900 psi in any aggregate condition and at temperatures ranging from -50′ F to + 800′ F. The various expansion coefficients of the valve components which arise during alternating thermal loads are fully compensated by the ring.
The double guidance of the piston in closed position prevent fluttering and vibration in the control setting, and oscillations in the tube.