Butterfly valve selection, first of all, according to successful engineering practice, relevant laws, and regulations, choose the appropriate structure, material, and pressure level to ensure that the butterfly valve is safe and reliable. Structure type ①The flow characteristics of the butterfly valve are approximately linear, whether it is midline type or eccentric type, the difference is not very big. The midline type is suitable as a regulating and small diameter process valve. ②How to choose double eccentric and triple eccentric butterfly valves, both structures have the characteristics of being able to disengage quickly and close tighter and tighter, so how to choose the two structures? As a soft seal with double eccentric, it is more convenient in processing and manufacturing. The triple eccentric is more complicated to process and manufacture, but it is more prominent in the tightening characteristics, and it is not easy to produce interference, so it is more suitable for metal hard seals. At present, there is no comprehensive analysis in the market, that what is recommended to use three eccentric metal hard seal is not right, especially on the large-diameter room temperature water system is recommended use, there is no need. Because the metal hard seal...
