Submarine construction is a multi-procedural coupled process. With the development of modular construction mode, its "outfitting" in a broad sense includes the whole process of material forming, structure building, equipment piping system manufacturing, installation and painting, in the design phase, precisely allocated top-level submarine outfitting plan can effectively influence the submarine construction process and ensure the overall functional performance.

With a focus on submarine outfitting between pressure and non-pressure hulls, the precision allocation process is suggested, the connotations and scope of the application of the precision allocation method based on the dimensional chain are discussed, and finally the key elements between pressure and non-pressure hulls and their precision control objects are identified according to the dimensional chain principle, and any unknown precision items throughout the outfitting process are allocated.

The allocation value of unknown precision items in the list of key outfitting items is obtained to meet construction precision requirements.

A precision allocation process and method, including materials, structures, equipment, and installation, is formed, which can be used to guide the processes and process designs of submarine outfitting.