is a control unit in fluid conveying system, with functions of cut-off, regulation, guidance, pressure regulator, pressure relief, diversion and effusion, preventing the reverse flow, etc. All kinds of valves from the most simple globe valve
to extremely complex and automatic control system have quite a wide varieties and specifications. The valve can be used to control air, water, steam, all kinds of corrosive medium, mud, oil, liquid metal, radioactive medium and other flowing of fluid. The connection way of valve and pipeline is one of important parameters, according to their connection, the classifications of valve are:
1. Threaded connection
: the valve body has internal thread or external thread connected with the threads of pipe.
2. Flanged connection
: the body has a flange connected with pipe.
3. Welding connection
: the body has a welding groove connected with the pipe.
4. Clamp connection: the body has a clip connected with the pipe.
5. Bite type connection: connected with pipe using card sets.
6. Wafer connection
: directly use bolts to clip the valve and pipe ends together.
The valve body
1. Metal materials: the valve body is made of metal materials, such as cast iron, carbon steel, alloy steel, copper alloy, aluminum alloy, lead alloy, titanium alloy, monel alloy, etc.
2. Non-metallic materials: the body is made of nonmetal materials, such as plastic, ceramic, enamel, glass fiber reinforced plastic, etc.
3. Metal lining: the external shape of valve body is made from metal, while every contact surface with medium is internal lining, such as rubber, plastic, ceramic, etc.