Objectives   As one of the key marine equipment technologies, drag chains can provide protection for pipelines on offshore platforms. In order to study the topological relationship and structural strength of drag chains, we take one large drag chain as the research object.

  Methods   First, according to the articulated relationship between the inner chain and outer chain, as well as the geometric dimension relationship between the articulated hole and circular arc groove of the inner chain plate, the topological relationships of drag chain are analyzed. The factors, rotation angle and pitch affecting the gyration radius of the drag chain are then acquired. Next, we adopt ANSYS Workbench to analyze the structural strength of the drag chain and obtain its structural response in an unloaded state. On this basis, we retain the original boundary conditions and increase the material density to simulate the stress state of a loaded drag chain, and the ultimate bearing capacity of the drag chain is acquired.

  Results  The results show that the articulated shaft at the turning of a drag chain bears the greatest stress.

  Conclusions   The findings of this paper show that drag chains are reliable in their use on offshore platforms.