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.