Butterfly valve shaft hole coaxiality guaranteeing machining system

The invention discloses a machining system for guaranteeing coaxiality of a butterfly valve shaft hole. The machining system comprises a machining clamping table and a drilling working device arranged on one side of the clamping table. A drilling rod is transversely connected to the drilling working device; a clamping plate is installed on the machining clamping table and used for placing and fixing the butterfly valve body, and a pair of clamping parts is arranged at the end, close to a drill rod, of the clamping plate, and the clamping parts are arranged on the left side and the right side respectively and can apply clamping acting force to the middle to clamp a flange part of the butterfly valve body. The clamping plate is further provided with a limiting sleeve, the limiting sleeve is provided with a limiting hole, and the limiting hole faces the direction of the drill rod and allows the drill rod to enter and be limited. Two butterfly valve shaft holes are tapped at a time through one drill rod, due to t