顶驱中心管强度有限元分析

中心管是顶驱的关键承载部件之一，其可靠性直接决定顶驱的工作性能。采用有限元法对中心管在额定栽荷和工作载荷2种工况下的应力、应变特性进行了研究，得出了中心管等效应力分布以及在各危险截面上定义路径的应力分布曲线。结果表明：在2种载荷工况下，中心管啮合螺纹具有承受载荷的能力，但前3牙和后4牙的齿根部应力过大，有可能发生粘扣和屈服破坏。

Finte Elemet Analysis in Center Pipe of Top Drive

During drilling operation, center pipe is one of the key loaded parts of top drive. So the reliability of center pipe directly affects the working performance of top drive. Using FEA, stress-strain properties of the center pipe under two kinds of loads were studied, i.e. rated load and working load. The distribution of equivalent effective stress and the stress envelope of the paths defined on dangerous cross-sections. Result shows that central pipe cannot be destroyed under the two kinds of load forms. But the stress of the front three and the end four threads root is oversize, so that the threads gluing and yielded failure possibly occurred.