The evolutionary history of butterfly valves

Update:05 Aug 2019
Summary:

The original butterfly valve is a simple, unclosed flap […]

The original butterfly valve is a simple, unclosed flapper valve. It is commonly used as a flow regulating valve and a damping valve in a water piping system. With the application of chemically resistant synthetic rubber on butterfly valves, the performance of butterfly valves is improved. Synthetic rubber has the characteristics of corrosion resistance, erosion resistance, dimensional stability, good resilience, easy forming, low cost, etc., and different performance synthetic rubbers can be selected according to different use requirements to meet the working conditions of the butterfly valve. Widely used in the manufacture of butterfly valve lining and elastic valve seat.

Because polytetrafluoroethylene (PTFE) has strong corrosion resistance, stable performance, is not easy to age, has low friction coefficient, is easy to form, and is dimensionally stable, and can improve its comprehensive performance by filling and adding appropriate materials to obtain better strength. The butterfly valve sealing material with lower friction coefficient overcomes some limitations of synthetic rubber. Therefore, the polymer polymeric material represented by polytetrafluoroethylene and its filling modified material have been widely used in butterfly valves, thus making butterfly valves The performance has been further improved, and a butterfly valve with a wider temperature, a wider pressure range, a sealing performance and a longer service life has appeared. In order to meet the requirements of industrial applications such as high and low temperature, strong erosion and long life, metal sealing butterfly valves have been greatly developed in the past decade. With the application of high temperature resistance, low temperature resistance, strong corrosion resistance, strong erosion resistance and high strength alloy materials in butterfly valves, metal sealing butterfly valves have been widely used in industrial fields such as high and low temperature, strong erosion and long life. Butterfly valves with large diameter (9750mm), high pressure (2.2kN/cm2) and wide temperature range (-102~606°C) have emerged, which has brought the butterfly valve technology to a new level.

Due to the wiping nature of the butterfly valve plate, most butterfly valves can be used for media with suspended solid particles and can be used for powdered and granular media depending on the strength of the seal.

The butterfly valve is a valve that opens and closes and adjusts the fluid passage by reciprocating about 90 degrees with a disc type opening and closing member. The butterfly valve is not only simple in structure, small in size, light in weight, low in material consumption, small in installation size, small in driving torque, easy to operate and fast, and also has good flow control function and closed sealing characteristics. One of the fastest growing valve varieties in the past year. Especially in the developed countries of the United States, Japan, Germany, France, Italy, etc., the use of butterfly valves is very extensive. The variety and quantity of the products are still expanding, and the development of high temperature, high pressure, large diameter, high sealing, long life, excellent regulation characteristics and multi-valve function, the reliability and other performance indicators are higher. Level, and has partially replaced the stop valve, gate valve and ball valve. With the advancement of butterfly valve technology. In the short-term foreseeable, especially in the field of large and medium-sized caliber, medium and low pressure, butterfly valves will become the dominant valve form.

Due to the application of computer-aided design (CAD) and computer-aided manufacturing (CAM) and flexible manufacturing systems (FMS) in the valve industry, the design and manufacture of butterfly valves has reached a new level. Not only has the valve design and calculation method been completely innovated, but also the heavy and repetitive routine design work of professional technicians has been alleviated, so that the technicians have more energy to improve the technical performance of the product and the research and development of new products, shortening the cycle and improving the cycle. Labor productivity. Especially in the field of metal sealing butterfly valves, due to the application of CAD/CAM, a three-dimensional sealing pair designed by CAD and manufactured by cAM numerical control has appeared, so that the sealing surface of the valve does not have any extrusion, abrasion and wear during the opening and closing process. Thus, the sealing and service life of the butterfly valve are increased by orders of magnitude.

When the butterfly valve is fully open, it has a small flow resistance. When the opening is between about 15° and 70°, it can perform sensitive flow control. Therefore, in the field of large-diameter adjustment, the application of the butterfly valve is very common, and Gradually become the dominant valve type.