Machining reference transmission method for large-scale casting cabin type structural parts

The invention relates to a machining reference transmission method for large-scale casting cabin type structural parts. Positioning surfaces and positioning holes are machined in two positioning blocks so as to serve as the reference of three-dimensional scanning; three-dimensional scanning is performed with the positioning surfaces and the positioning holes adopted as reference; a scanning resultis compared and fitted with a casting model, so that the casting model can be completely enveloped by scanning data; coordinate rotation and translation data obtained when the scanning result is converted into the casting model are recorded, relationships between the positioning holes in the positioning blocks before and after fitting are provided for machining; and the positioning surfaces and the positioning holes are machined according to coordinate relationships which are obtained after coordinate rotation and translation. According to the method, the three-dimensional scanning means is applied to the determinati