密封总成内凸缘接触应力影响因素研究

Research on Influencing Factors of Contact Stress of Seal Assembly Inner Flange

为研究水下井口头系统密封总成与套管悬挂器外壁接触应力的变化规律,以密封体内凸缘为研究对象,在密封机理分析的基础上,建立了密封总成安装力学模型,分析了驱动套筒位移载荷、环槽宽度和过盈量对接触应力的影响规律。分析结果表明:在内凸缘半径一定时,内凸缘与套管悬挂器外壁的接触应力与挤压力有关,驱动套筒位移载荷、环槽宽度和过盈量都会对挤压力产生影响,通过调整三者参数的大小,内凸缘接触应力也会随之发生变化;在环槽宽度为定值的条件下,内凸缘与套管悬挂器外壁的接触应力随着位移载荷的增大而增大;位移载荷在10~22 mm时,接触应力随着过盈量的增大而逐渐增大;在过盈量为定值的条件下,内凸缘与套管悬挂器外壁的接触应力随位移载荷的增大而增大,但增幅逐渐减小。所得结果可为水下井口头系统密封总成的结构设计与研究提供理论依据。

To study the change law of the contact stress between the seal assembly of the subsea wellhead system and the outer wall of the casing hanger,the inner flange of the sealing body is taken as the research object.Based on the analysis of the sealing mechanism,a mechanical model of the seal assembly installation is established and analyzed.The influences of driving sleeve displacement load,ring groove width and interference on contact stress are discussed.The analysis results show that when the radius of the inner flange is constant,the contact stress between the inner flange and the outer wall of the casing hanger is related to the compression force.The displacement load of the driving sleeve,the width of the ring groove and the interference will affect the compression force.By adjusting the size of the three parameters,the contact stress of the inner flange will also change accordingly.By giving the width of the ring groove,the contact stress between the inner flange and the outer wall of the casing hanger increases with the displacement load.When the displacement load is 10~22 mm,the contact stress gradually increases with the interference.When the interference is fixed,the contact stress of the inner flange and the outer wall of the casing hanger increases with the displacement load,but the increase gradually decreases.The results obtained can provide a theoretical basis for the structural design and research of the seal assembly of the subsea wellhead system.