English 
The wear-resistant ball valve is evolved from the function of the plug valve. Its opening and closing member is a ball core, and the valve switch is realized by rotating the valve stem 90 degrees. The wear-resistant ball valve is mainly used for cutting, distributing and changing on the pipeline. The flow direction of the medium, the V-shaped ball valve designed as a V-shaped opening also has good flow regulation performance.
The reason why it is widely used in modern industrial situations is because the ball valve opens and closes quickly, has good sealing performance, simple structure and low flow resistance.
The structure of the ball valve is classified according to:
According to the structural form, the fully welded ball valve can be divided into a fixed ball valve, a floating ball valve, a track ball valve, a V-shaped ball valve, an eccentric hemisphere valve, a three-way ball valve, a four-way ball valve, and the like;
According to the connection method, it can be divided into flange ball valve, ball valve, internal thread stainless steel Ball Valve, external thread ball valve, welded ball valve, clamp ball valve (generally sanitary ball valve), card sleeve ball valve, etc.
According to the sealing material, it can be divided into soft sealing ball valve and metal hard sealing ball valve.
Soft-sealed ball valves are generally suitable for media with a temperature of less than 150 degrees. For media above 150 degrees, PPL seals or carbide metal seals are used.
Small-diameter ball valves, generally used floating electric ball valve, large-diameter ball valves, because the required opening and closing torque is relatively large, often choose fixed ball valve, can reduce the torque required when opening and closing, improve the reliability of work. V-type ball valves and eccentric hemisphere valves can be used to regulate flow, and three-way ball valves and four-way ball valves are used to reverse fluids.
Ball valves are commonly used in carbon steel, 304 stainless steel, 316 stainless steel. For corrosive medium, the valve body and the sphere are fully lined with PTFE.
The driving method of the ball valve mainly includes electric, pneumatic and worm gear transmission. Compared with the small-diameter 3 way ball valve, the handle is generally used to open and close.
Fire valves are widely used in the next three major industries
It is understood that the market size of the cryogenic globe valve industry in 2013 has expanded a lot compared with last year. This is a very obvious fact. Until 2013, there were more than 700 fire-fighting valve manufacturers and traders, and even more than 200 trade inquiries per day. It is obvious that the fire-fighting valve supply and demand market is heating up. From the preliminary analysis of the first quarter data, it can be concluded that the fire valve demand market is 20 percentage points higher than last year.
In the past ten years, with the development of China's fire valve (valve industry dynamics) industry, the variety specifications of fire-fighting valves are also increasing, and more and more industries are applying fire-fighting valves, such as petrochemical industry, oil refining industry, nuclear power industry, thermal power industry. And so on have a wide range of uses. Let us take a look at the development prospects of the fire valve in the following three major industries.
Petrochemical industry: The competition in the petrochemical industry has been fierce. The requirements for fire-fighting valve equipment are also the most stringent. The future fire-fighting valves will cooperate with industrial automation to promote the overall level of fire-fighting valve equipment and develop multi-functional, high-efficiency, low-consumption petrochemicals. Fire valve equipment. The annual output value of China's petrochemical enterprises is in the hundreds of billions, which shows that China has a large fire valve market (valves, pumps), we should consider from the perspective of market changes, to ensure stability and development.
Refining industry: After 60 years of development in China's refining industry, the scale of production has expanded rapidly. Driven by a series of policy measures, the output value and output of China's refining industry continued to grow in 2010, and structural adjustment was gradually advanced, maintaining a good momentum of development. In 2010, the refining industry achieved an output value of 2.4252 trillion yuan, a year-on-year increase of 38%. Therefore, it can be seen that China's refining industry fire valve application market space is huge.
Nuclear power industry: Fire-fighting valves are the basic equipment for nuclear power equipment in this industry, accounting for roughly 5-10% of capacity. China will continue its nuclear power development plan. In 2015 and 2020, nuclear power installed capacity will reach 40GW and 75GW respectively. China will restart the approval of new nuclear power projects around mid-2012. Therefore, in this field, new products and equipment must be continuously introduced to meet market demand.
In addition, fire protection valves are required in the construction and boiler industries as well as in special industries. In particular, the use of 3 Piece Ball Valves is very extensive and is used in many enterprises. This fully demonstrates that the development of fire-fighting valves is very rapid and has good prospects. At the same time, more and more industry applications have more new requirements for fire valve products, and the quality and technical requirements for fire valves are also getting higher and higher.
