6M型往复压缩机轴系扭转振动分析

Torsional Vibration Analysis of 6M Type of Reciprocating Compressor Shaft System

扭转共振是大型往复压缩机轴系破坏失效的主要原因之一。针对某6M型往复压缩机用集中质量法建立轴系质量圆盘刚度杆物理模型,将模型的转动惯量矩阵和扭转刚度矩阵代入运动学微分方程,用传递矩阵法求解轴系的模态,通过轴系模态的分析指导压缩机轴系方案设计,进而避免扭转共振的发生。进一步通过动态响应计算,校核轴系两处危险截面的扭转疲劳强度,确保轴系在设计工况下运行不会发生扭转破坏。本文的分析方法能为往复压缩机轴系的设计与扭转振动校核提供参考。

Torsional resonance is one of the main reasons for the shaft failure of big type of reciprocating compressors. For a 6M style reciprocating compressor, this paper established a reasonable shaft stiffness-mass disk model on the base of lumped-mass method. Further, the model's moment of inertia matrix and torsional stiffness matrix was plugged into dynamical differential equations. The modal of the shaft system was calculated with the transfer matrix method. Then, the torsional resonance can be avoided by the check of the calculated modal. Moreover, the torsional fatigue strength of two dangerous sections was verified based on the dynamic re-sponse calculation. It guaranteed the torsion failure not happen when the compressor operating at its design condition. The method applied in this paper can guide the shaft system design and the verification of reciprocating compressors.