Ball valve structure introduction

Ball valve is a common type of valve, its structure is relatively simple and powerful, widely used in a variety of fluid pipeline systems. The following is a detailed description of the ball valve structure:

First, the main components

Ball valve mainly consists of the following parts:

1. Sphere: As a closing element, the sphere is usually round and spherical, and a channel is formed in the middle to control the on-off of the pipeline by rotating the sphere. The ball material is diverse, commonly used stainless steel, copper, cast iron, etc., to adapt to different working environments and media requirements.

2. Seat: Seat is the positioning device of the ball, usually made of metal material, plastic or elastic material. The seat cuts a groove on the spherical surface of the ball, and the ball rotates with the seat to form a seal to prevent media leakage.

3. Valve stem: The valve stem is the shaft that runs through the center of the sphere, one end is connected to the sphere, and the other end is connected to the operating mechanism. Through the rotation or push of the operating mechanism, the valve stem drives the ball to rotate and realize the opening and closing of the pipeline.

4. Operating mechanism: including manual operating mechanism and automatic operating mechanism. The manual operation mechanism is usually composed of a handle, a gear, etc., which controls the movement of the ball through manual rotation or pushing; The automatic operating mechanism may include an electric motor, a pneumatic mechanism, etc., which controls the movement of the ball through electrical or air pressure signals.

5. Valve body: The valve body is the shell of the ball valve, which is used to accommodate the ball, the seat and other components, and provide the medium flow channel. The design of the valve body usually takes into account the pressure and temperature of the medium and the sealing performance of the valve.

Second, the working principle

The working principle of the ball valve is relatively simple: the valve is opened and closed by rotating the ball 90 degrees. When the ball is rotated parallel to the sealing surface of the valve seat, the medium can pass unimpeded through the gap between the ball and the valve seat; When the ball is rotated perpendicular to the sealing surface of the valve seat, the flow of the medium is cut off. This design makes the ball valve with fast opening and closing, good sealing performance, wear resistance and so on.

Third, classification

According to different classification standards, ball valves can be divided into a variety of types:

1. Classification by structure: floating ball valve and fixed ball valve. The ball of the floating ball valve will move under the pressure of the medium to form a seal; The position of the ball of the fixed ball valve is fixed, and the sealing is achieved by moving the seat.

2. Classified by driving mode: manual ball valve, electric ball valve and pneumatic ball valve, etc. Manual ball valve through the manual operation of the handle to control the valve opening and closing; The electric ball valve and the pneumatic ball valve drive the movement of the valve through electricity and compressed air respectively.

3. According to the sealing material classification: soft seal ball valve and hard seal ball valve. Soft seal ball valve using rubber or polytetrafluoroethylene soft materials as seals; Hard sealed ball valves use metal materials as seals to adapt to harsh environments such as high temperature and high pressure.

4. According to the use of medium classification: water ball valve, steam ball valve, gas ball valve and acid and alkali ball valve. Different types of ball valves are suitable for different media and working conditions to ensure the normal operation and long service life of the valve.

5. Classified by connection mode: flange type ball valve, sandwich type ball valve, thread type ball valve and other connection modes to adapt to the installation needs of different pipeline systems.

In summary, the ball valve structure design is reasonable and powerful, which can meet the control needs of various fluid pipeline systems. In the selection and use of ball valves, it is necessary to select the appropriate type and specification according to the specific working conditions and medium requirements to ensure the normal operation and long-term service life of the valve.