Teach You How To Select a Valve

Feb. 10, 2020

Globe valve supplier to share with you: Most of the media in chemical production equipment have the characteristics of high toxicity, flammable, explosive and corrosive, complex and harsh working conditions, high operating temperature and pressure, once the valve appears Malfunctions can cause medium leakage in the lightest cases, and stop or stop the production of the devices in serious cases, or even cause serious accidents. Therefore, scientific and reasonable selection of valves can not only reduce the construction cost of the device, but also ensure the safe operation of production.

Key points of valve selection:

1. Define the use of the valve in the equipment or device:

Determine the working conditions of the valve: the nature of the applicable medium, the working pressure, the working temperature and the control method.

2.Select the correct valve type

The correct choice of valve type is based on the designer's full mastery of the entire production process and operating conditions as a prerequisite. When selecting the valve type, the designer should first grasp the structural characteristics and performance of each valve.

3. Determine the end connections of the valve

The first two are most commonly used in threaded connections, flanged connections, and welded end connections. Threaded valves are mainly valves with a nominal diameter of less than 50mm. If the size of the diameter is too large, it is very difficult to install and seal the connection.

Flange-connected valves are more convenient to install and remove, but are heavier and more expensive than screw-connected valves, so it is suitable for pipe connections of various diameters and pressures.

Welded joints are more reliable than flanged joints and are suitable for more severe conditions. However, it is more difficult to disassemble and reinstall the welded valve, so its use is limited to places that can usually run reliably for a long time, or where the conditions are high and the temperature is high.

Globe Valve

Globe Valve

4.Selection of valve material

When selecting the material of the valve housing, internal parts and sealing surface, in addition to considering the physical properties (temperature, pressure) and chemical properties (corrosiveness) of the working medium, you should also master the cleanliness of the medium (with or without solid particles). In addition, it is also necessary to refer to the relevant regulations of the country and the user department.

Correct and reasonable selection of the valve material can obtain the most economical service life and the best performance of the valve. The valve body material selection sequence is: cast iron-carbon steel-stainless steel, and the seal ring material selection sequence is: rubber-copper-alloy steel-F4.

5.Other

In addition, the flow rate and pressure level of the fluid flowing through the valve should be determined, and the appropriate globe valve should be selected using the existing data (such as valve catalogs, valve product samples, etc.).