Valve is an indispensable control element in fluid system, widely used in petroleum, chemical, electric power, metallurgy, water treatment and other fields. There are many types of valves, and each type has its own unique characteristics and application scenarios. This article will introduce several common valve types and their characteristics.

1. Ball Valve

Ball valve is famous for its simple structure, good sealing performance and rapid opening and closing. It opens or closes the channel by rotating the sphere 90 degrees, and there is a hole inside the sphere with the same diameter as the pipe. Ball valve is suitable for low temperature (not more than 150℃), high pressure and large viscosity media and require rapid switching of pipeline parts. Its advantages are low fluid resistance and simple maintenance, but the price is relatively high.

2. Gate valve

Gate valve is mainly used for general steam, water pipeline full open or full closed operation. The gate valve is characterized by small installation length, non-directional, small medium flow resistance when fully opened, and good sealing performance. However, the processing of gate valve is more complicated, and it is not easy to repair after the sealing surface is worn. Gate valves can be divided into open rod type and dark rod type according to the condition of the valve stem, and can be divided into parallel type and wedge type according to the structural characteristics of the gate plate. Gate valve is widely used in water supply and drainage, oil, natural gas and other industries backbone pipeline.

3. Stop valve

The globe valve is mainly used to cut off the medium path, and can also adjust the flow rate and pressure. The globe valve is characterized by simple manufacture, low price and good adjustment performance, but the installation length is large, the flow resistance is large, the sealing property is poor, the sealing surface is easy to wear, but the maintenance is easy. According to the structure, the globe valve can be divided into straight-through, right-angle and direct-flow, which is suitable for steam, hot water and other systems that need to accurately adjust the flow rate.

4. Butterfly valve

The butterfly valve is mainly used for full-open and full-close operation on low-pressure medium pipelines or equipment. The butterfly valve is characterized by small size, simple structure, convenient opening and closing, rapid and less labor. The butterfly valve controls the fluid by rotating the disc disc, and the disc can be rotated 90 degrees to achieve the state from fully closed to fully open. Butterfly valves are widely used in water treatment, chemical, food and other industries for regulating flow and switching control.

5. Check valve

Check valve is the use of its own structure and the pressure difference between the valve in front of the valve after the valve to automatically open and close the valve, its role is to make the medium only do one direction of flow, and prevent its reverse flow. Check valve according to the structure can be divided into lift type and swing type, the former is suitable for small caliber horizontal pipe, the latter is suitable for large caliber horizontal or vertical pipe. The check valve is located at the outlet of the pump, the outlet pipe of the trap, and other places where the reverse flow of fluid is not allowed.

In addition, there are many types of valves such as plunger valves, safety valves, traps, and balance valves, each with its own unique characteristics and application scenarios. The correct selection and use of valves can effectively improve the safety and efficiency of the system and reduce production costs. When selecting valves, factors such as the nature of the medium, working pressure, temperature, flow rate and the specific requirements of the pipeline system should be comprehensively considered.