High-voltage electron beam welding method for steam turbine spacer plate

The invention discloses a high-voltage electron beam welding method for a steam turbine spacer plate. The steam turbine spacer plate comprises a plate body, an outer ring and a blade grid. The method includes the steps that S1, the plate body, the outer ring and the blade grid are machined to be of full-circle structures and assembled together, and then demagnetizing is performed to achieve qualification; S2, high-voltage vacuum electron beam welding is adopted for welding the assembled plate body, outer ring and blade grid into a whole. The problem that split residual magnetism is excessively large, and it is not allowed to demagnetize a split to be smaller than 5 Gauss is avoided, magnetic blow will not be generated in high-voltage vacuum electron beam welding, the defects of incomplete fusion and others will not be generated, and the welding quality of weld joints can be improved.