水平井分段压裂投球滑套承压接触分析

鉴于国内还没有成熟的裸眼完井配套工具,研制了适合苏里格气田的水平井分段压裂投球滑套,并针对投球滑套在压裂施工中到位不明显的问题,利用有限元分析软件ANSYS建立了投球滑套的接触模型,分析了不同压力对低密度球和球座变形与应力分布的影响。分析结果表明,施工压力由10 MPa增至20 MPa时,接触压力近似线性变化,当压力从20 MPa增加到50 MPa时,球和球座之间开始产生塑性变形,接触面积增加,从而使接触压力增加变慢。当压力为50 MPa时,球座最大应力值达到358 MPa,超过了低密度球和球座的屈服强度而发生了塑性变形,但是没有达到材料的屈服极限,满足压裂施工的要求。

Pressure Bearing and Contact Analysis of Ball Injection Sliding Sleeve in Horizontal Well Staged Fracturing

Due to the fact that there is no mature matching tool for open hole completion in China,the ball injection sliding sleeve for horizontal well staged fracturing suitable for Sulige Gasfield was developed.In light of the problem that the sleeve is not noticeably in place in fracturing operation,the finite element analysis software was adopted to establish the contact model of the sleeve and analyze the effect of different pressures on low-density ball,ball seat deformation and stress distribution.The analysis shows that when the operation pressure changes from 10 MPa to 20 MPa,the contact pressure is approximate to a linear change.When the pressure increases from 20 MPa to 50 MPa,the plastic deformation occurs between ball and ball seat,the contact area increases and the contact pressure increase slows down.When the pressure is 50 MPa,the maximum stress value of the ball seat reaches 358 MPa,exceeding the yield strength of low-density ball and ball seat to cause plastic deformation.But it does not reach the yield limit,satisfying the field operation requirement.