Strong-sealing non-rising stem gate valve

The utility model discloses a strong-sealing non-rising stem gate valve which improves the sealing performance of a gate plate and a valve seat and is long in service life. A mounting groove is formedin one side wall of each gate plate groove; a rotating part is rotationally connected into the mounting groove; a sealing ring is fixed on the rotating part; a transmission part extending into the inlet groove is arranged at the upper part of the sealing ring; a gate plate is slidably connected into the inlet groove. Fixing blocks are arranged at the upper parts of the flashboards; a screw rod isfixed on the fixed block; a rotating rod is rotationally and hermetically connected to the valve cover; the rotating rod extends into the valve cover and is fixedly connected with a mounting frame; anut in spiral transmission connection with the screw rod is fixed at the lower part of the mounting frame; a sealing plug is arranged at the lower end of the fixing block, located on the outer side of the transmission part and