The engineering of salvaging a wreck requires a variety of auxiliary equipment. It often affects the overall construction efficiency because of the cumbersome installation and disassembly of auxiliary fittings and placement problems. In order to solve the problems, based on the size and working condition of a 120 t gantry lifting device used for wreck salvage, this paper designs and transforms the base of gantry. In this paper, Abaqus was used to check the strength of the redesigned base. And we conducted dock trials. The result shows that the base can meet the strength requirements of 120 t gantry lifting device. In addition, it can be quickly installed and disassembled. This device can be matched with other auxiliary equipment used for salvage. It provides reference for the quick installation and disassembly of other equipment used for salvage. In order to improve the construction efficiency.