College of Mechanical and Engineering, Xi’an University of Science and Technology
Engineering Research Center of Expressway Construction & Maintenance Equipment and Technology of MOE,Chang’ an University
Shaanxi Taihe Intelligent Drilling Co., Ltd.

S135钢级钻杆在矿井勘探、探放水、瓦斯抽采等钻孔施工中得到了广泛使用。然而,由于钻杆接头螺纹承受轴向拉压、扭转、弯曲及其复合载荷的循环作用,导致接头螺纹的使用寿命远远低于其设计寿命,是整个钻杆结构中最薄弱的环节。因此,通过万能拉伸试验获得钻杆接头材料的力学性能参数,经计算转化得到其本构参数,对钻杆接头进行有限元分析。为了提高有限元分析效率,推导垂直于钻杆接头轴线的螺纹截面轮廓几何表达式,基于旋转、抬升、缩径和连接节点的设计思路,提出了一种考虑钻杆接头锥度和台肩的三维螺纹参数化建模方法,并根据单元和节点之间的关系开发了钻杆接头连接的参数化三维六面体网格建模程序,通过与交互式建模方法计算结果的对比验证了其有效性和可行性。此外,对上扣扭矩、压扭及压弯扭复合载荷作用下接头外螺纹的力学特性进行了分析。结果表明:3种工况下钻杆接头外螺纹上的应力近似呈现“浴盆”形态,第1螺纹牙上的应力最大;随着圈次的增加,螺纹牙上的应力迅速下降,最后一圈螺纹牙上的应力呈现上升趋势;在弯矩的作用下,螺纹牙上的应力具有非对称特征。在接头螺纹设计时,必须考虑井眼曲率的影响并且需要重点关注接头压缩边第1螺纹牙上的应力。

S135 steel drill pipe has been widely used in drilling construction such as mine exploration, water exploration and gas extraction. However, due to the cyclic effects of axial tension, compression, torsion, bending, and their composite loads on the threads of drill pipe joints, the service life of the joint threads is far lower than their design life, making them the weakest link in the entire drill pipe struc- ture. Therefore, the mechanical properties of drill pipe joint material were obtained by tensile test, and its constitutive parameters were calculated and transformed to obtain the finite element analysis of the drill pipe joint. In order to improve the efficiency of finite element analysis, the geometric expression of the thread section profile perpendicular to the axis of the drill pipe joint was derived. Based on the de- sign ideas of rotation, lifting, reduction radius and connection nodes, a three - dimensional thread para- metric modeling method considering the taper and shoulder of drill pipe joint was proposed. Based on the relationship between elements and nodes, a parametric 3D hexahedral mesh modeling program for drill pipe joint connection was developed, and its validity and feasibility were verified by comparing with the calculation results of interactive modeling method. Furthermore, mechanical characteristics of the joint external thread under the combined load of make - up torque, compression and torque, com- pression and torque and bending were analyzed. The analysis results indicate that: The stress on the ex- ternal thread of the drill pipe joint under three working conditions shows an approximate “ bathtub” shape, with the maximum stress on the first tooth. With the increase of the number of turns, the stress on the thread teeth decreases rapidly, and the stress on the last round of thread teeth shows an upward trend. Under the action of bending moment, the stress on the thread teeth exhibits asymmetric charac- teristics. When designing joint threads, it is necessary to consider the influence of wellbore curvature and pay special attention to the stress on the first thread tooth of the compression edge of the joint.

国家自然科学基金项目(52075551);高速公路筑养装备与技术教育部工程研究中心(长安大学)开放基金项目(300102253512)

赵宽,崔强,李金平,等.S135钻杆接头螺纹三维参数化建模及力学特性分析[J].西安科技大学学报,2024,44(2):391-399.

ZHAO Kuan, CUI Qiang, LI Jinping, et al. Three-dimensional parametric modeling and mechanical characteristic analysis of S135drill pipe joint thread[ J] . Journal of Xi’an University of Science and Technology, 2024, 44( 2) : 391-399.