Large cylinder inner wall measuring and pre-adjusting device and detection method

The invention belongs to the technical field of cylinder automatic detection and automatic leveling, and particularly relates to a large cylinder inner wall measuring and pre-adjusting device and a detection method. Comprising a mother board assembly, a daughter board assembly, an axial displacement assembly and a detection assembly. The axial displacement assembly is installed on the rotary table and is perpendicular to the horizontal plane in the axial direction. The daughter board assembly comprises a daughter board frame, a height adjusting mechanism and a radial adjusting mechanism, a barrel supporting surface is formed at the top of the daughter board frame, zero-point positioning upper bodies in one-to-one correspondence with zero-point positioning lower bodies in the mother board assembly are arranged on the daughter board frame, and the zero-point positioning upper bodies and the zero-point positioning lower bodies are jointed to form zero-point positioning, so that the daughter board assembly and th