CD-GF型钻井球阀阀体的力学特性分析

CD-GF型钻井球阀阀体的结构最为薄弱,其外壳的开孔部位常出现开裂现象,影响钻井作业的正常进行。为此,运用ANSYS Workbench工程分析软件,对6种结构方案的CD-GF型钻井球阀阀体在压、拉、扭载荷作用下的力学特性进行详细的数值分析。研究结果表明:在不同拉力、内压和工作扭矩的组合作用下,相对于原阀体结构A,其他5种方案(A1、A2、B、B1和B2)在最大应力上减小的平均值分别为16. 4%、36. 0%、7. 6%、23. 2%和40. 7%,总变形量减小的平均值分别为16. 7%、37. 3%、22. 9%、30. 6%和45. 5%;在6种球阀阀体结构方案中,最大应力部位均出现在与阀体轴线垂直的孔壁上,随着与圆孔区域距离的增大,其应力值减小;在所有拉力、内压和工作扭矩的组合作用下,阀体的最大应力均小于其材料的极限抗拉强度,其力学行为处于材料弹性变形阶段;拉力载荷是影响钻井球阀阀体强度的主要因素;结构B2(外径增大28mm+双边开孔方案)对原阀体结构A的增强效果最好。研究结果可为钻井球阀阀体的结构优化与改进提供基础数据。

Analysis of Mechanical Properties of CD-GF Type Drilling Ball Valve Body

The CD-GF drilling ball valve body is the weakest part of the valve,resulting in frequent cracking of the opening of the outer casing,which affects the drilling operations. To address the problem,the ANSYS Workbench engineering analysis software is used to perform detailed numerical analysis of the mechanical properties of the CD-GF valve body with six structural solutions under pressure,tension and torsion loads. The results show that under the combination of different tension,internal pressure and working torque,compared with the original valve body structure A,the other five schemes( A1,A2,B,B1,B2) have the average maximum stresses decreased by16. 4%,36. 0%,7. 6%,23. 2%,40. 7%,and the average total deformation reduction of 16. 7%,37. 3%,22. 9%,30. 6%,45. 5%,respectively. Of the six kinds of ball valve body structure schemes,the maximum stress point all appears on the hole perpendicular to the axis of the valve body. As the distance from the hole increases,the stress value decreases. Under the combination of tensile force,internal pressure and torque,the maximum stress of the valve body is less than the ultimate tensile strength of the material,and its mechanical behavior is in the elastic deformation stage of the material. The tensile load is the main factor affecting the strength of the valve body. The B2 structure( the outer diameter is increased by 28 mm + bilateral opening) has the best enhancement effect compared with the original valve body structure A. The study results can provide basic data for structural optimization and improvement of the drilling ball valve body.