Establish the main purpose of the valve in the facility or equipment, and clarify the operating standards of the valve: applicable medium, pressure, and operating temperature; for example, if you want to choose a French LIT globe valve, determine that the medium is steam, and the principle is 1.3MPa, the operating temperature is 200 °C.
Specify the nominal diameter, pipe diameter, and interface method of the pipeline connected to the valve: flange, external thread, electric welding, etc.
Clarify the actual method of operating the valve: manual, electric, electromagnetic induction, pneumatic, or hydraulic control valve, hydraulic push rod linkage, etc.; for example, a manual globe valve is selected.
According to the medium, pressure and operating temperature transmitted by the pipeline, the raw materials of the shell and main parts of the valve are clearly selected: steel casting, carbon steel, stainless steel plate, carbon steel, stainless acid-resistant steel, gray cast iron, malleable cast iron, ductile iron, alloy Copper, etc.; such as steel casting materials selected for globe valves.
Select the type of valve: cable digital TV valve, adjustment valve, safety valve, etc.;
Define the form of the valve: globe valve, globe valve, valve, butterfly valve, one-way throttle valve, pressure regulating valve, steam trap, etc.;
Clarify the main parameters of the valve: For fully automatic valves, the allowable fluid density, discharge capacity, back pressure type, etc., must be specified first, and then the nominal diameter of the pipeline and the aperture of the high-pressure gate valve hole must be specified;
Identify the main graphic parameters of the selected valve: construction length, flange connection method and specifications, specifications of the relative height of the valve after opening and closing, size and total number of anchor bolt holes for connection, appearance specifications of all valves, etc.;
Use the original materials: valve product catalogs, valve product samples, etc., to select appropriate valve products.
