Nominal Diameter And Sealing Form Of Forged Steel Stop Valve

The nominal diameter of Forged Steel Globe Valve is usually subdivided according to the standard pipe size. The commonly used subdivision method is to classify according to DN (nominal diameter). The following are the common subdivisions of the nominal diameter of forged steel stop valves:

1. Small-diameter forged steel stop valve: generally refers to forged steel stop valves with DN ≤ 50mm (2 inches).

2. Medium-diameter forged steel stop valve: refers to forged steel stop valves with DN between 50mm (2 inches) and 150mm (6 inches).

3. Large-diameter forged steel stop valve: refers to forged steel stop valves with DN greater than 150mm (6 inches).

It should be noted that this is only a common subdivision method, and the specific subdivision may vary according to different countries, regions or industry standards. When purchasing forged steel stop valves, it is necessary to select the appropriate nominal diameter according to the size requirements of the actual pipeline system. In addition, factors such as the working pressure level, material, and sealing form of the valve need to be considered to ensure that the selected forged steel stop valve can meet the actual application requirements.

Forged steel stop valves usually have the following common sealing forms:

1. Soft seal: The soft seal form in forged steel stop valves mainly uses rubber, polytetrafluoroethylene (PTFE) and other materials as sealing rings, and achieves sealing through elastic deformation. Soft seals have good sealing performance and can prevent leakage. It is suitable for general working conditions, including water, oil, gas and other media.

2. Metal seal: The metal seal form in forged steel stop valves mainly achieves sealing through metal-to-metal contact. Metal seals can be divided into two forms: metal-to-metal contact seals and metal-to-metal gap seals. Metal seals have high pressure resistance and corrosion resistance, and are suitable for high temperature, high pressure and corrosive media working conditions.

3. Welding seal: The welding seal in forged steel stop valves is sealed by welding connection, and the valve body and valve seat and other components are directly welded together to form a seamless connection. This sealing form is suitable for high temperature, high pressure and special working conditions, and has good pressure resistance and corrosion resistance.

It is necessary to select the appropriate sealing form according to the specific working conditions and medium characteristics. At the same time, factors such as valve material, operating temperature and pressure must also be considered to ensure the sealing performance and reliability of the valve.