Low-operating-torque plug valve with replaceable valve sleeve seal and working method thereof

The invention discloses a low-operating-torque plug valve with a replaceable valve sleeve seal and a switch working method thereof. The low-operating-torque plug valve comprises a valve body, a valve cover, a valve rod and an operating device. By designing the replaceable valve sleeve, the problem that the sealing performance is reduced due to abrasion after the valve is used for a long time is solved, the sealing specific pressure between the plug body and the valve body is ensured, and the interchangeability of sealing pieces is achieved. In addition, an oil cavity between the valve rod and the operating device is designed to be variable, so that the operating torque of the plug body in the opening and closing process is reduced, and abrasion of the valve sleeve between the plug body and the valve body is reduced. The service life of the valve is prolonged, the use cost of the valve is reduced, the valve can be quickly opened and closed under extreme conditions due to the characteristic of low operation tor