Disassembly and assembly tool of diesel engine exhaust valve and valve seat and method

The invention discloses a disassembly and assembly tool for a diesel engine exhaust valve and a valve seat. The disassembly and assembly tool includes an upper clamping ring, a lower clamping ring, aplurality of tightening bolts and a plurality of screws, wherein the upper clamping ring and the lower clamping ring are arranged at an upper and lower interval and are of the same structure, the upper clamping ring and the lower clamping ring include a first upper curved clamping ring body, a second upper curved clamping ring body, a first lower curved clamping ring body and a second lower curvedclamping ring body correspondingly, and a curved convex rib of the upper clamping ring and a curved convex rib of the lower clamping ring are matched with a corresponding exhaust valve limiting groove and a corresponding valve seat limiting groove correspondingly. A method includes the steps that (A1), the upper clamping ring and the lower clamping ring are used for clamping a corresponding exhaust valve and a correspondi