The expanding gate valve is a high performance gate valve with outstanding features. This type of valve possesses functions of double & bi-directional sealing and reinforced mechanical sealing. It is full bore and feasible for pipe pigging, and is widely used in pipelines of subterranean heat steam, petroleum, natural gas production, transmission, collection and storage. It is also suitable for corrosive fluids like coal gas, acid, alkali and etc. Full bore suitable for pipeline pigging, smooth path, small flow resistance and no pressure loss.
Valve body is an integral casting piece which has adequate rigidity against external force in pipeline. It is full port, circle shape and through conduit, this makes small loss of pressure and pipe pigging feasible. No matter if the valve is fully open or fully closed, the fluid is insulated from valve cavity, this feature allows the operator to release the pressure through vent & drain fittings in an emergency situation. The unique top-entry design enables professional maintenance personnel to change the internal parts of the valve in-line. Due to bi-directional sealing design, the pressure entrapped in valve cavity cannot be released to down stream through downstream seat; the pressure may rise because of temperature change or other reasons. In this case, the pressure in valve cavity can be released by a safety device in valve body so that to assure the safe running of the pipeline and facilities.
The installation location of this kind of valve is diverse; it can be vertical, horizontal, backward or slanting. Stem packing Material can be replaced safely in-line. The fully-enclosed structure has perfect protection property and it is all-weather suitable.
