Selection Characteristics of Ball Valves

The Stainless Steel Ball Valve 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. The ball valve designed as a V-shaped opening also has a good flow adjustment function.

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, small in installation size, and small in driving torque within a certain nominal diameter range. It is simple to operate and easy to achieve rapid opening and closing. One of the fastest growing valve varieties in more than ten years. Especially in developed countries such as the United States, Japan, Germany, France, Italy, West, and Britain, the use of ball valves is very extensive, and the variety and quantity of use continue to expand. Life, excellent adjustment performance and multi-function development of a valve, its reliability and other performance indicators have reached a higher level, and have partially replaced gate valves, globe valves, and throttle valves. With the advancement of ball valve technology, in the foreseeable short time, there will be more extensive applications in oil and gas pipelines, oil refining and cracking units, and the nuclear industry. In addition, ball valves will also become one of the leading valve types in large and medium-sized calibers and low- and medium-pressure fields in other industries.

The working principle of the ball valve is to make the valve unblocked or blocked by rotating the valve stem. The ball valve switch is light, small in size, can be made into a large diameter, reliable in sealing, simple in structure, easy to maintain, the sealing surface and the spherical surface are often closed, and it is not easy to be eroded by the medium, and it is widely used in various industries.

The ball valve and the plug valve are the same type of valve. Only its closing part is a ball. The ball rotates around the center line of the valve body to achieve opening and closing.

Stainless Steel Ball Valve

The ball valve is a new type of valve that has been widely used in recent years. It has the following advantages:

1. The fluid resistance is small, 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 in plastics with good sealing performance, and it has also been widely used in the vacuum system.

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

5. Convenient maintenance, simple structure of the ball valve, generally movable sealing ring, easy 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, and the medium will not cause erosion of the valve sealing surface when the medium passes.

7. It has a 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.

Ball valves have been widely used in petroleum, chemical, liquefied gas, water supply and drainage, food, pharmaceuticals, power generation, papermaking, urban construction, minerals, boiler steam systems, municipal administration, atomic energy, aviation, rockets and other departments, as well as people's daily life.

The ball valve is mainly used to connect or block the pipeline medium, especially in the parts that require rapid opening and closing, such as emergency unloading. Because of its simple structure, fewer parts, light weight, and good sealing performance, its application is becoming more and more extensive. Structure: Mainly composed of valve body, valve cover, sealing valve seat, ball and valve stem. The ball with a hole is the core of the ball valve. The ball is controlled by the rotation of the valve stem to open and close, and the rotation is the full switch.

Ball valves can be divided into two categories: Floating Ball Valves and fixed ball valves. The characteristic of the floating ball valve is that the ball can float freely. According to the different structure of the seal seat, it is divided into two types: fixed seal seat and movable seal seat. The structure of the floating ball valve with fixed sealing seat is shown in the figure. Two fixed sealing seat made of fluorine plastic are installed in the valve body, and a floating ball made of carbon steel or stainless steel is clamped between the two seats. , The ball has a circular through hole, when it is opened, the channel opens; when the valve stem rotates, the ball hole is perpendicular to the valve channel, and the ball is pressed against the back seat by the pressure of the medium to ensure the seal of the valve.

The main selection principles of ball valves:

1. For oil and natural gas pipelines, pipelines that need to be cleaned, and buried underground, use full-diameter, fully-welded ball valves; for buried underground, select full-diameter welded or flanged ball valves ; For branch pipes, use flanged, welded, full-diameter or reduced-diameter ball valves.

2. For the transportation pipeline and storage equipment of refined oil, use flanged ball valves.

3. Floating ball valves with flange connection and internal thread connection are used on the city gas and natural gas pipelines.

4. In the oxygen pipeline system in the metallurgical system, a fixed ball valve that has undergone strict degreasing treatment and flanged connection should be used.

5. For the piping system and device of low-temperature medium, a low-temperature ball valve with bonnet should be used.

6. In the pipeline system of the catalytic cracking unit of the oil refining unit, a lifting rod type ball valve can be used.

7. All stainless steel ball valves made of austenitic stainless steel with polytetrafluoroethylene as the seat and sealing ring should be used in the equipment and piping systems of corrosive media such as acid and alkali in the chemical system.

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

9. When flow adjustment is needed, a worm-gear drive, pneumatic or electric ball valve with V-shaped opening can be selected.

The company also provides you Three-Way Ball Valve and mini ball valve, please feel free to contact us if necessary