Bolt joint is the main form of spacecraft structure assembly. This paper aimed at the problems that standard torque spanner is not suitable to tightening torque

analyzed and summarized two causes. One reason is caused by limited axial space of fasteners

the other reason is limited radial space of fasteners. Based on thorough analysis of fastening principles and principle of type serialization

a scheme of integrated L-shaped is established. The results of experimentation indicate that the scheme of integrated L-shaped lever is reasonable along with the requirement of developing long-life and high reliability spacecraft. Therefore the stability of fasteners is greatly enhanced.