First, the ball valve introduction The ball valve is a valve that uses a ball with a circular passage as a starting and closing member, and the ball rotates with the valve stem to realize the opening and closing action. The opening and closing member of the ball valve is a holed ball that rotates about an axis perpendicular to the passage to achieve the purpose of opening and closing the passage. Ball valves are primarily used to open and close pipes and equipment media. Second, the main advantages of the ball valve are as follows: Suitable for frequent operation, quick and easy opening and closing. The fluid resistance is small. The utility model has the advantages of simple structure, relatively small volume, light weight and convenient maintenance. Good sealing performance The flow direction of the medium can be arbitrary regardless of the installation direction. No vibration, low noise. Third, the main disadvantages of the ball valve are as follows: According to the structure, the ball valve can be divided into: floating ball valve, fixed ball valve, elastic ball valve and oil seal ball valve; according to the channel can be divided into straight energy type, angle type and three general formula, etc., the three types can be divided into T shape and L shape two Kind. According to the connection work, it can be divided into three types: threaded connection, flanged connection and welded type. Ball valve installation and maintenance should pay attention to the following: To leave the position of the handle rotation Cannot be used for throttling. Ball valves with drive mechanisms should be installed upright.