The upper shell is one of the key parts of the TVS-2 M high burn up nuclear fuel assembly using in Tianwan Nuclear Power Plant

which has the irreplaceable important function such as lifting fuel assembly

the control rods entrance

buffering and damping

ect. The upper shell has the characteristics of many components

complex structure

high requirements in dimensional accuracy and welding quality. The product production cycle

repair rate

rejection rate are high in the initial stage of localization trial production

resulting in serious process bottleneck. To ensure the quality of the product of nuclear reactor

it is necessary to study to grasp its core technology. The ultimate realization of manufacturing technology localization of the upper shell

to improve quality and reduce cost. In view of welding equipment modification

welding fixture design

productivity improvement

introduce the research work of manufacturing technical difficulties of automatic welding technology of the upper shell localization. The design of the research derivative has applied for 4 related utility model patents and been authorized.