Submodule-assembled three-dimensional positioning mounting method

The invention discloses a submodule-assembled three-dimensional positioning mounting method. The mounting method comprises the following steps: (1) selecting and burying datum points; (2) establishing a plane coordinate system; (3) positioning module boundary lines and central angle control lines; (4) establishing a height datum system; (5) adjusting the elevations of all modules at the bottom to be qualified; (6) controlling the position line of an inclined plate and the elevation of a WP point; (7) setting out the position line and the angle line of a peripheral circular plate, and measuring the perpendicularity; (8) controlling the position line and the elevation of an inside circular plate and measuring the perpendicularity; (9) measuring the control line and the elevation of a top cover; (10) after assembly is finished, repeatedly measuring. In the assembly process, each submodule needs to be measured and the three-dimensional coordinate of each submodule is measured; then, according to a series of technical data of welding contraction, the final position of each submodule is determined, and the assembling precision requirement is achieved; finally, the parameters such as the size and position of the module need to be converted into the position in a nuclear island coordinate system, so that the accurate position of the module in a nuclear island is determined.