海洋修井机是整个修井作业的必要设备，海洋修井机井架是修井机最关键的承载部分，所受到的载荷较大，常由于强度和稳定性不足造成严重的事故。基于修井机井架主要是以静力学性能作为设计准则，并未考虑井架的小模块化和轻量化要求，仅通过增加杆件材料用料来保证井架的安全性和可靠性，存在巨大的材料浪费。所以在保证井架的安全性和可靠性的同时，为实现海洋修井机井架轻量化设计，从而减少材料用量，具有十分重要的工程意义。通过模拟退火算法研究了井架轻量化，结果表明，轻量化后的井架静力学、动力学和稳定性均符合行业标准。可见海洋修井机井架轻量化研究的准确性较高，研究方法和结果可为修井机井架结构优化提供理论依据及数据参考。

Sea workover machine is used as the necessary equipment for the whole workover operation, its derrick is the most critical bearing part of workover machine, with large load and serious accidents are often caused due to insufficient strength and stability. Based on the static performance of the derrick is mainly used as the design criterion, and it does not consider the small modularity and lightweight requirements of the derrick. There is a huge material waste only by adding the materials of the rod material to ensure the safety and reliability of the derrick. So it provides very important engineering significance while the safety and reliability of the derrick are ensured, in order to realize the lightweight design of offshore workover rig and reduce the material consumption. The simulation annealing algorithm was used to investigate the lightweight of the derrick. The results show that the industry standard is met by the statics, dynamics and stability of the lightweight derrick. It can be seen that the accuracy of light weight study of offshore workover rig is high. The theoretical basis and data reference can be provided by the research methods and results for the structural optimization of derrick of workover rig.