What is ball valve?

 

The ball valve is evolved from the cock. Its opening and closing part is a sphere, which uses the sphere to rotate 90 degrees around the axis of the valve stem to achieve the purpose of opening and closing. The ball valve is mainly used to cut off, distribute and change the direction of the medium flow in the pipeline, and it also has a function of good flow adjustment with a V-shaped opening. The ball valve is not only simple in structure, good in sealing performance, but also small in size, light in weight, low in material consumption and small in driving torque within a certain nominal diameter range, besides, It is simple to operate and easy to achieve rapid opening and closing. The variety and quantity of ball valves are still expanding, and are developing towards high temperature such as high temperature stainless steel ball valves, high pressure like high pressure ball valves stainless steel, high sealing, long life, excellent adjustment performance and multi-function of one valve.

 

 

What are the advantages of ball valve?

 

Ball valve is a new type of valves that has been widely used in petroleum, chemical, liquefied gas, water supply and drainage, food, pharmaceuticals, power generation, paper-making, urban construction, minerals, boiler steam systems, municipal administration, atomic energy, aviation, rockets and other departments, as well as people's daily life. Why is ball valve used in so many industries? It has the following advantages:

 

1. Small fluid resistance, and its resistance coefficient is equal to that of a pipe section of the same length.

 

2. Simple structure, small size and light weight.

 

3. It is tight and reliable. At present, the sealing surface material of the ball valve is widely used plastic, which has good sealing performance, and has been widely used in vacuum systems.

 

4. Easy operation, fast opening and closing, only need to rotate 90° from fully open to fully closed, which is convenient for remote control.

 

5. Convenient maintenance, simple ball valve structure, and the sealing ring is generally movable, making it easier to disassemble and replace.

 

6. When fully open or fully closed, the sealing surface of the ball and the valve seat is isolated from the medium. When the medium passes, it will not cause erosion of the valve sealing surface.

 

7. Wide range of applications, with a diameter ranging from a few millimeters to a few meters, and can be applied from high vacuum to high pressure.

 

How to select ball valve?

 

Since the ball valve has been widely used in various industries, there are many different kinds of ball valves. Stainless steel ball valves can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media,  and its material is divided into 304, 321, 316 stainless steel ball valve; Stainless steel 3 piece ball valve and gate valve are the same type of valve. The difference is that its closing part is a sphere. The sphere rotates around the center line of the valve body to achieve opening and closing; Stainless steel 3 way valve has T type and L type. The T-type can connect three orthogonal pipelines with each other and cut off the third channel, which can split and merge. The L three-way ball valve type can only connect two orthogonal pipelines, and cannot maintain the third pipeline to communicate with each other at the same time, only playing a distribution role. How to select the ball valves, there are some selection principles of ball valve.

 

1. Full-diameter, fully-welded ball valves can be used for oil and natural gas transmission main lines, pipelines that need to be cleaned, and buried underground; Full-diameter welded or flanged ball valves can be selected for buried underground; Flange connection, welding connection, full bore or reduced diameter ball valve can be used for branch pipes, .

 

2. Stainless steel flanged ball valves can be used for the transportation pipeline and storage equipment of refined oil.

 

3. Stainless steel ball float valves with flange connection and internal thread connection are used on city gas and natural gas pipelines.

 

4. A fixed ball valve that has undergone strict degreasing treatment and flanged connection should be selected in the oxygen piping system in the metallurgical system.

 

5. A low-temperature ball valve with a valve cover should be selected for the piping system and device of low-temperature medium, .

 

6. A lifter-type ball valve can be used in the pipeline system of the catalytic cracking unit of the oil refining unit.

 

7. It is advisable to use all stainless steel ball valves made of austenitic stainless steel and PTFE as the seat sealing ring in the equipment and piping system of corrosive media such as acid and alkali in chemical system.

 

8. Metal-to-metal sealing ball valves can be used on piping systems or devices for high-temperature media in metallurgical systems, power systems, petrochemical plants, and urban heating systems.

 

9. A worm gear driven, pneumatic or electric ball valve with V-shaped opening can be selected when flow adjustment is required.