Metal diaphragm tightening method and equipment based on temperature control stress

The invention discloses a metal diaphragm tightening method and equipment based on temperature control stress. The method comprises the following steps: constructing a first shell-solid part model of a metal diaphragm and upper and lower pressing rings; dividing shell unit grids of a metal diaphragm and entity unit grids of upper and lower pressing rings, and applying attributes and thermodynamic parameters of a material to the corresponding unit grids; setting a displacement loading boundary condition, a contact limiting condition and an initial temperature field parameter, and setting a temperature-displacement coupling type analysis step to obtain stress distribution after the diaphragm is cooled to room temperature and bearing reaction information of the compression ring; copying a second shell-solid grid model, modifying initial temperature field parameters for multiple times, setting temperature-displacement coupling type analysis steps, and summarizing to obtain a relation curve of stress along with th