关键词: 钻柱设计, 安全系数法, 判别式, 两种方法, 余量法, 设计问题, 拉力载荷, 钻杆, 抗拉力, 设计方法

Abstract: 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.