油田修井机井架的力学分析与优化设计

修井机井架承受着主要的载荷，如果设计不当，会浪费原材料，甚至在使用中出现事故。在对修井机井架进行有限元分析的基础上，得到了一种新井架结构。改进后的整个井架应力分布趋于均匀，最大应力比原结构降低12％。受压稳定性分析表明，改进设计的整体稳定性较好，完全可以保证井架的正常工作。对井架的模态分析表明，井架的固有频率与底盘发动机、绞车的工作频率不同，因此当绞车在不同转速下工作时，不会发生共振。将有限元分析技术、结构优化技术与大型设备设计相结合，为设计师提供了主动设计的依据，提高了修井机的技术含量和设计水平，同时，也为其他产品应用结构优化设计技术提供了有价值的参考。图3表l参16

Mechanical analysis and optimization design of oilfield workover derricks

A workover derrick is subject to primary loads, and the challenge facing design engineers is that a derrick has to be designed to be strong enough to bear those loads without wasting materials. A new derrick structure is designed on the basis of the finite element analysis of workover rigs. The distribution of the whole derrick stress is symmetrical in the new design. The maximal stress of the new structure is lower by 12 percent than the previous one. The stability analysis under pressure indicates that the whole stability is preferable, and can assure the normal work of the oil derrick. The modeling analysis shows that the inherent frequency of the oil derrick is different from that of the chassis engine and winch, so the resonance phenomena will not take place when the winch works at different rotary speeds.