What are the causes of the rotation failure of the ball of the square brick rod plug valve?

What are the causes of the rotation failure of the ball of the square brick rod plug valve? The square brick rod plug valve is a ball valve with drill string thread at both ends It is to prevent liquid splashing in such a special place as drilling He is an important part of the blowout prevention system in the drill string, and his structure is simple, installation is very convenient, and the use efficiency is very stable However, in use, sometimes it will encounter that the rotation of the square brick rod plug valve loses its function and the ball can not rotate normally, which seriously affects the normal use of drilling What are the reasons for these situations? Problems between ball valve and valve seat in the use of square brick rod plug valve, problems between ball valve and valve seat, very easy to cause the valve body can not rotate There are two kinds of problems between ball valve and valve seat One is that the friction torque between the two is too large, which causes the normal operation of the ball to be blocked Another is serious corrosion between the two, which requires regular maintenance by users The problem of valve seat can also cause that the square brick rod plug valve can not rotate normally The problem of valve seat is a big factor of Zui In use, the valve seat has a serious plastic change, which directly affects the use of the valve body There is also a solid particle stuck between the valve seat and the ball, which will also affect the use of the square brick rod plug valve These problems are caused by abnormal use of the valve body, which requires the user's attention to reduce the occurrence of accidents.