Selection Principles of Valves

The selection of valves should be based on the following principles.

Meeting the requirements of production processes
Valves should meet the needs or requirements of media, working pressure, operating temperature, usage, etc., which is the most basic principle of the valve selection. If you need the valve to play the role of overpressure protection or to discharge the needless media, you should choose the safety valve or the overflow valve. If you need the valve to prevent the back-flow of media in the operating process, the check valve should be your first choice. If you not only need the valve to automatically discharge the continuously generated condensate water, air and other incondensable gases in the steam pipes and equipment, but also to prevent the escape of steam, the steam trap valve is supposed to be selected. In addition, when the media are corrosive, the valves to be picked up should be made of materials with good corrosion resistance.

Safety and reliability
The valves applied to the petrochemical, power plants, metallurgical and other industries are required to have continuous, stable and long-term operation. Therefore, the valves are supposed to have high reliability as well as high safety factor so as to avoid the leakage of valves and causing personal injury accidents resulted from the failures of valves. Long-term operation of the valves can bring long-term continuous production for enterprises, which means creating more benefits for enterprises. It is of great significance to build clean and civilized factories and to implement HSE (healthy, safe, environmental) management.

Convenient operation, installation and maintenance  
After the valve is installed, the direction of the valve, the opening mark, etc. should be identified by the operator clearly and correctly so that the operator can timely and decisively deal with various emergency failures of the valve. At the same time, the structure of the selected valve should be as simple as possible, which will make installation and maintenance convenient and easy.
 
Economy principle
On the premise of meeting the normal use requirements of the pipeline, it is recommended that valves with relatively low manufacturing costs and the simple structure should be used to reduce the costs of the device, which will not only avoid not making full use of the valves, but also will decrease the installation and maintenance costs of the valves in the future.