(1) Selection steps

1. Clarify the use of the valve in the equipment or device, and determine the working conditions of the valve: applicable medium, working pressure, working temperature, etc.

2. Determine the nominal diameter and connection method of the pipeline connected to the valve: flange, thread, welding, etc.

3. Determine the way to operate the valve: manual, electric, electromagnetic, pneumatic or hydraulic, electric linkage or electro-hydraulic linkage, etc.

4. Determine the materials of the selected valve housing and internal parts according to the medium, working pressure and working temperature conveyed by the pipeline: gray cast iron, malleable cast iron, ductile iron, carbon steel, alloy steel, stainless acid-resistant steel, copper alloy, etc.

5. Choose the type of valve: closed circuit valve, regulating valve, safety valve, etc.

6. Determine the type of valve: gate valve, globe valve, ball valve, butterfly valve, throttle valve, safety valve, pressure reducing valve, steam trap, etc.

7. Determine the parameters of the valve: For automatic valves, determine the allowable flow resistance, discharge capacity, back pressure, etc. according to different needs, and then determine the nominal diameter of the pipeline and the diameter of the valve seat hole.

8. Determine the geometric parameters of the selected valve: structural length, flange connection form and size, the size of the valve height direction after opening and closing, the size and number of bolt holes connected, the overall valve size, etc.

9. Use existing data: valve product catalogs, valve product samples, etc. to select appropriate valve products.