As an important facility for offshore oil development, offshore platforms are prone to damage in harsh environments, such as seawater immersion and impact, which affects their safety. As a high stress concentration area, tubular joints are more prone to be damaged in offshore platforms. Therefore, the detection of tubular joints is of great significance. In order to adapt to the damage detection of the tubular joints that are the special structures on offshore platforms, using eddy current thermography, the structure of the tubular joints and the distribution of eddy currents induced on the surface of the tubular joints are considered, three forms of coil were designed: Round table coil, delta coil and flat double coil, and the corresponding simulation was completed by SolidWorks and COMSOL. In order to meet laboratory requirements, the actual models of coils and the workpiece to be measured were manufactured. The accuracy of the simulation and the effectiveness of the designed coils were verified through experiments and MATLAB data processing. The results show that the flat double coil has better heating effect on the tubular joints of offshore platforms, and can be used to detect the damage defects.