桅杆式钻塔的模态分析研究

Study on modal analysis of mast derrick

针对在钻探过程中,在多种复合的动载荷作用下,钻塔将发生振动和变形的问题,以桅杆式钻塔为例,对钻塔的动态性能进行研究。首先通过模态试验验证了模态仿真的正确性,然后分别从钻塔结构和动力头在钻塔不同位置两方面进行模态分析,获得了钻塔模态频率、振型随钻塔臂尺寸和装配距离的变化规律,分析了动力头在不同位置时钻塔的模态特征及其变化趋势。研究成果能对钻塔的结构优化及钻机的自动控制提供理论指导和数据支撑,同时有利于提升钻探效率,减少孔内事故。

The derrick vibrates and deforms under the compound action of various dynamic loads during drilling process. Taking the mast derrick as the example, the paper studied the dynamic performance of the derrick. First, the modal simulation proved correct via modal test, and then the modal analysis was conducted from the derrick structure and the location of the power head on the derrick. After that, the modal frequency of the derrick, as well as the variation laws of vibration mode with the dimension and the assembly distance of the derrick column were obtained. In addition, the modal features of the power head at various location and its variation tendency were analyzed. The study results offered theoretical guidance and data support for the structural optimization of the derrick and the automatic control of the drill rig, which was helpful for enhancing the drilling efficiency and reducing in-hole accidents.