钻柱静拉设计及其判别式

钻柱的各种载荷中,拉伸载荷是主要载荷.因为它数量大而且作用在整个作业过程中.因此钻柱的设计,尤其是深井钻柱的设计,一般都是考虑拉伸载荷.有两种确定计算拉伸载荷的方法,即拉力余量法和安全系数法,然而长期以来并未确定这两种方法各自的使用条件,这就为钻柱设计带来不便.本文讨论钻柱静拉设计问题并提出判别式和曲线,用以在拉力余量和安全系数两者中选择设计方法,使问题简捷地得以确定.

DESIGN AND CRITERION OF A DRILL PIPE UNDER TENSION

Among the various loads of a drillpipe,the tension load is the major one,since it is large in quantity and it is acting during the entire process of operation.Therefore the drillpipe design,in particular in a deep well,generally is made in considering the tension load.There are two methods which may be used for determining the tension load in calculation,i.e.,the margin of overpull method and the safety factor method.However,there have been no definite rules of application of these two methods in drill pipe design.Then it has brought the inconvenience to the drillpipe design.This paper discusses the design of a drill pipe under tension,and presents a criterion and curves for selecting between the margin of overpull and the safety factor.The whole problem is thus settled in a fast and easy way.