Postweld heat treatment device and process for large and thick steel plate

The invention discloses a large and thick steel plate postweld heat treatment device and process. The device is composed of a moving platform, a medium-frequency power source, a first cooling assembly, a power supply, a numerical control platform, a second cooling assembly, an auxiliary power source, an adjustable support assembly and a heating assembly. The medium-frequency power source, the first cooling assembly, the power supply, the numerical control platform, the second cooling assembly and the auxiliary power source are reasonably arranged on the upper end face of the movable platform, the first end of the adjustable support assembly is fixedly connected with the upper end face of the movable platform, and the upper end face of the heating assembly is fixedly connected with the second end of the adjustable support assembly. The heating assembly mainly comprises a first coil, a first magnetizer, a second coil, a second magnetizer, an auxiliary electrode, a first linear module, a second linear module and