Special tool for disassembling and assembling valve seat of high-temperature and high-pressure valve

The utility model relates to a special tool for disassembling and assembling a valve seat of a high-temperature and high-pressure valve. The special tool comprises a stress plate, a pull rod, a clamping nut and a lifting unit, one end of the pull rod is fixed to the stress plate, the clamping nut is in threaded fit with the other end of the pull rod, the clamping nut is a special-shaped nut, and the side face of the clamping nut comprises two opposite conical faces and two opposite planes. The distance between the two opposite planes and the axis of the clamping nut is smaller than the distance between the two opposite conical faces and the axis of the clamping nut. The lifting unit is connected with the stress plate, and when the lifting unit operates, the stress plate moves in the direction away from the clamping nut. The special tool for disassembling and assembling the valve seat of the high-temperature and high-pressure valve can be suitable for valve seats of different sizes only by machining clamping n