特殊扣套管接头的应力及密封特性分析

以特殊扣螺纹接头为分析对象 ,采用非线性有限元素法 ,分析了套管接头在上扣扭矩、轴向拉伸和内部压力作用下的受力特性。获得了这种特殊扣套管接头密封段、台肩面、螺纹啮合扣面以及管体的应力分布。结果表明 ,采用过盈配合来模拟上扣扭矩的方法具有较好精度。套管接头的薄弱区域在啮合螺纹承载面根部 ,该区域具有显著的应力集中。密封面接触压力随套管内部压力的增大而增大 ,轴向拉力对其影响很小 ,在本文的设计载荷作用下可以保证良好的密封特性

Stress and Sealing Property Analysis of Premium Threaded Connection

Nonlinear finite element method is adopted in the stress and sealing property analysis of premium threaded connection, and an enquivalent calculating method for the make up torque is also proposed. The deformations, stresses and strains in the sealing section, shoulder zone, thread surface and tubing body are calculated for the threaded connection under axial tensile loads and internal pressures. The results indicate that the critical zone of the threaded connection located at the root of thread tooth where there is a severe stress concentration. When the connection is full make up, the maximum deformation occurred at the sealing zone and shoulder platform, and the maximum axial press stress located on tubing body near the first tooth. A study on the contact pressure at sealing zone of the preminum connection shows that the sealing performance can be ensured under design loading condition. The seal pressure increases with the increasing of internal pressure, and slightly decreases with axial tensile.