The high performance butterfly valves are simple, it is small and lightweight, and its installed size is small too. Butterfly valves can fast switching, and it can 90 ° back and forth rotation, its drive torque is small. What's more, it has the good flowing-control function and seal-off characteristics at the same time. In the occasions with large and medium caliber as well as low and middle pressure, butterfly valves are the dominant forms in valves. When butterfly valve is fully opening, the thickness of butterfly-board is only resistance when the medium is flowing through the valve, so the resistance generated by this valve is small, so it has the good flowing-control characteristics. In the aspect of sealed type, it can be divided into two types, namely, the elastic sealed type and metal sealed type. The seal on elastic sealed butterfly valve can be inserted on the valve or attached around the butterfly-board. The service life of metal sealed valve is generally longer than that of the elastic sealed valve, but metal sealed valve is difficult to be completely sealed. Metal sealed valve can adapt to the situation with relatively higher temperature, while the elastic sealed valve is affected by the temperature limit. If PTFE butterfly valves are required to be the flowing-controller, the key is to correctly choose the size and type of butterfly valves. The structural principle of butterfly valves is particularly applied to make the large-diameter valves. Butterfly valves can not only be widely used in oil, gas, chemical, water processed and other general industries, they can be also applied in the cooling water system of the thermal power plant. The commonly-used butterfly valves have two kinds, namely, wafer butterfly valve and flanged butterfly valve. The wafer butterfly valve is to use the stubs to connect the valve between the flanges of two pipelines. The flanged butterfly valve is the valve with flange, it is using stubs to connect the flanges on the two sides of the valve to the flange on the pipeline. With the applications of the anti-corrosive synthetic rubber and wafer type butterfly valve, the performance of butterfly valve can thus be enhanced, and it can fulfill the different working conditions. In the recent decade, metal sealed butterfly valve has gotten rapidly development. With the applications of high-temperature-proof, low-temperature-proof, corrosion-proof, erosion-proof and high-strength alloys in the butterfly valve, metal sealed butterfly valves are thereby widely used in the high-temperature, low-temperature, strong erosion and other working conditions, and butterfly valves are partially replaced globe valves, gate valves and ball valves. Butterfly valves can transport mud, and it will accumulate the least liquid in the pipe outlet. When it is under the low pressure, it can achieve the good sealed performance.

Stainless steel fittings and alloy steel manifold are mainly used in the fields of kitchen appliances, transportation, construction, civil engineering. Area in the kitchen appliances, washing tank and the main electrical, gas water heaters, home appliances are mainly automatic washing machine drum. Energy saving and recycling from the environmental point of view, the demand for stainless steel pipe fittings and duplex stainless steel reducer are expected to further expand. Mainly in the field of transport vehicles and railroad cars exhaust system, stainless steel pipe fittings stainless steel exhaust system for each vehicle in about 20- 30kg, the world's annual demand of about 100 million tons, which is stainless steel pipe fittings and stainless steel manifolds most applications. In the construction field, the recent sharp increase in demand, such as: Singapore subway station guards, using the approximately 5,000 tons of stainless steel outer Veneer. Another example of Japan after 1980, for construction of stainless steel increased by about 4 times, mainly for the roof of the building materials inside and outside decoration and structure. 80 years, coastal areas in Japan using 304-type material as the roofing materials without coating, Stainless Steel Pipe forged pipe fittings from rust to consider gradually changing for the use of coating of stainless steel pipe fittings. Threaded pipe fittings into the 90's, high corrosion resistance developed more than 20% of high Cr ferrite system stainless steel pipe fittings, is used as roofing materials, and aesthetics in order to develop a variety of surface finishing techniques.