以大型往复式压缩机曲轴为研究对象, 采用Box-Behnken试验设计对曲轴结构进行优化设计, 达到降低曲轴系的扭振幅值和自由端扭转角的目标。首先采用田口设计试验法从多个曲轴结构的设计参数中筛选出对曲轴系强度及扭转性能影响较大的显著因子, 然后采用Box-Behnken试验设计法对显著因子进行优化, 得出曲轴结构设计参数的最终优化值。通过对8列全平衡曲轴的曲柄厚度、中心圆盘厚度和与大端曲柄销长度进行优化结果显示, 压缩机曲轴系在一个周期内的峰值应力和自由端扭转角与优化前相比分别下降了22.4%和4.5%, 这表明, 优化后曲轴系的强度提高, 扭振幅值降低。研究结果为大型多列曲轴的研究设计提供了有效理论和有效证据。

Taking the crankshaft of large reciprocating compressor as a research object, Box-Behnken experimental design is used to optimize the crankshaft structure, so as to reduce the torsional amplitude of crankshaft system and the torsional angle of free end. Firstly, Taguchi design test method is used to select the significant factors which have great influence on the strength and torsion performance of the crankshaft system from the design parameters of multiple crankshaft structures. And then, Box-Behnken experimental design method is used to optimize the significant factors, and the final optimization value of crankshaft structural design parameters is obtained. Finally, by optimizing the crank thickness, the center disk thickness and the length of the large end crank pin of eight fully balanced crankshafts, it is shown that the peak stress and the free end torsion angle are reduced by 22.4% and 4.5% respectively in one cycle compared with those before optimization, which indicates that the strength of the crankshaft system is increased and the torsion amplitude is reduced after optimization. The research results provide effective theory and evidence for the research and design of large multi-row crankshaft.