ZJ15型钻机底座的模态测试分析

针对钻机底座在钻进中动特性差和振动剧烈的缺点，运用振动理论和测试原理，对ＺＪ１５型钻机底座在实际钻井条件下的模态进行了动态测试。经信号采集、系统处理和模态测试分析，得到底座的频响函数曲线，并识别出２００Ｈｚ以内的各阶模态参数。测试结果表明，采用４挡钻进时，底座振动剧烈的主要原因是钻台面上钻井设备的工作频率或工作频率的２倍、３倍接近底座的固有频率。通过测试钻机底座的模态参数，可相应调整钻井设备的工作频率，使之避开底座的共振频率；或测试现役底座的模态参数，调整结构的部分构件或质量分布，改变结构的刚度来改变底座的共振频率，从而减小振动。

Modal testing and analysis of Model ZJ15 rig substructure

According to vibration theory and testing principle, the frequency response function curves of Model ZJ15 drilling rig substructure which is being used are obtained by means of dynamic testing, signal acquisition and processing and modal analysis, and the modal parameters of each order within 200Hz are identified. The result of the testing shows that the main cause of the violent vibration is that the working frequency of the drilling equipment and its double and triple frequencies are close to the natural frequencies of the substructure while drilling in the forth rotation speed. By testing the modal parameters of the rig substructure, the working frequency of the drilling equipment can be adjusted accordingly to avoid the resonance frequency; and by testing the modal parameters of the servicing substructure and adjusting the part of the members or quality distribution of the substructure and changing the rigidity of the structure to vary the resonance frequency of the substructure, the vibrati