【摘要】 为了解RTTS封隔器卡瓦在井下的力学行为,优化其结构参数和提高其承载能力,利用弹性力学楔形体应力分析方法分析了RTTS封隔器卡瓦的应力分布及强度,确定了卡瓦牙根部的应力集中系数与集中应力,同时根据井下卡瓦的平衡条件,导出了RTTS封隔器卡瓦在井下承受的真实轴向载荷的计算公式。算例分析结果表明:(1)卡瓦下端面牙齿受力较大,该点为应力危险点,而卡瓦端面最薄处牙齿受力则较小;(2)相同轴向载荷作用下,封隔器卡瓦在不同套管尺寸下的应力分布不同;(3)增大卡瓦片数、牙面长度、牙面宽度及卡瓦楔角等结构参数可以有效降低卡瓦的相当应力。因此,校核RTTS封隔器卡瓦的强度应以其牙根部应力危险点为依据。更多还原

【Abstract】 To understand the downhole mechanical behavior of RTTS packer slip,optimize its structural parameter and improve its bearing capacity,the elastic mechanical wedge stress analysis method was used to analyze the stress distribution and strength of RTTS packer slip. The stress concentration coefficient and concentrated stress of the slip tooth root were determined. Meanwhile,the calculation formula of the real axial load that the downhole slip bears was derived according to the balance condition of downhole slip. The calculation example offers the following results. First,the lower end face of slip bears remarkable force; this point is the dangerous point of stress; the thinnest place of slip end face bears relatively small force. Second,the stress distributions of packer slip with casings of different dimensions are different due to the effect of the same axial load. Third,increase of structural parameters,such as number of slips,tooth surface length,tooth surface width and slip wedge angle,can effectively decrease the equivalent stress of slip. Therefore,the verification of the RTTS packer slip strength should be based on the dangerous point of its tooth root.更多还原