Clamping device for machining outer circle of straight pipe section of large bent pipe

The utility model relates to the technical field of machine manufacturing, in particular to a clamping device for machining the outer circle of a straight pipe section of a large bent pipe. Comprising a base, an upper connecting base, an inclined connecting base and a lower connecting base, the upper connecting base, the inclined connecting base and the lower connecting base are fixedly arranged on the base, the outer circle of the base is clamped and fixed through a clamping jaw of a lathe chuck, the upper connecting base is provided with a horizontal clamping space used for clamping a vertical section of a bent pipe, and the inclined connecting base is provided with an inclined clamping space used for clamping a corner section of the bent pipe. The lower connecting base is provided with a vertical clamping space used for clamping the horizontal section of the bent pipe, and the bent pipe is clamped and fixed to the upper connecting base, the inclined connecting base and the lower connecting base through the