Gate Valves |
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Gate Valves, often referred to as "Stop" or "Block Valves", are the most common style valve in existence and they play a major role in virtually every refinery, chemical plant, power plant and industrial facility in the world. These valves are manufactured in sizes ranging from 1/4 inch to 144 inches. Gate valves are manufactured in virtually every metal from aluminum to zirconium as well as a variety of engineered plastics. The most common materials are steel, iron and bronze. One of the most recognized advantages attributed to gate valves is that in the open position, they do not restrict flow and by design they are able to stop flow from either direction. Most gate valves consist of a body and a bonnet that contains a closure element, called a disc or wedge. The closure element can have one of two different disc designs : tapered or parallel. Both operate on the principle of a closure element disc or wedge (gate) sliding into a slot in the pipeline and closing off the fluid path. The tapered disc of the "wedge gate" valve is machined to match a pair of body seats set at the same angle, usually about 10 degrees. The gate is attached to a stem that passes through the bonnet of the valve, ultimately interfacing with a hand wheel or other device to operate the stem to open and close the valve. As the tapered disc engages the seats, it locks firmly in place stopping the flow. Three types of wedge gates are available: solid disc, one piece flexible, and two piece split design. Pressure around the stem is contained by packing material that is compressed into a packing area or chamber.
Recommended Uses: Advantages: Disadvantages:
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