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The carbon/glass hybrid rod exhibits high tensile strength, light weight, and strong corrosion resistance. However, the bottleneck of interlayer splitting exists in the interlayer hybrid rod, severely impeding safe operation. To solve the problem of rod splitting, this paper proposed a new scheme of an intralayer carbon/glass hybrid rod. Based on the material constitutive model, a full‐scale simulation model was developed. The stress distribution and deformation of the hybrid rod were analyzed and the progressive damage mechanism of the hybrid rod was explained. The results indicated that, for the intralayer carbon/glass hybrid rod, (a) the ultimate experimental tensile load witnessed a significant increase, rising by 14.0% from 452.4 to 515.7 kN compared to the interlayer hybrid rod; (b) the numerical model predicted the tensile load of 525.9 kN, with an error of 1.9% compared to the test result, meeting engineering accuracy requirements; (c) the elastic deformation stage saw a 146.7% increase from 280.2 to 691.3 MPa in the maximum axial stress of the carbon‐fiber layer, and a 120% increase from 89.8 to 198.0 MPa in the maximum radial stress of the glass fiber layer as the tensile displacement increased from 0.16 to 0.32 mm. In conclusion, the intralayer carbon/glass hybrid rod proposed in this paper can significantly improve the tensile strength compared to the interlayer hybrid rod, which can accelerate the application of carbon/glass hybrid rods in oil and gas fields. Highlights: According to the problem of interlayer splitting in the interlayer carbon/glass hybrid rods, a novel scheme of an intralayer carbon/glass hybrid rod was proposed.Based on the material constitutive model, a full‐scale simulation model of an intralayer carbon/glass hybrid rod was developed to analyze the stress distribution and deformation response under tensile load.The dynamic progressive damage analysis method for intralayer carbon/glass hybrid rods was proposed to reveal the damage evolution mechanism. [ABSTRACT FROM AUTHOR]

Up to date, compression packers have been widely utilized to seal annular space between tubing and casing in the fracturing process of low permeability reservoirs. However, packer end damage under great annulus pressure difference and internal shear failure caused by excessive pressure in tubing are the main failure reasons. Current research works mainly focus on the theoretical model of sealing property with contact stress as evaluation index and less consideration was given to pressure-bearing property in rubber. This paper established a novel analytical model which took into account material properties, geometric dimension and borehole expansion ratio setting the maximum shear stress as evaluation criteria, which can investigate the distribution of shear stress along the axial diameters on compression packer under one end loaded and other end fixed. Also, the accuracy of the analytical model was verified by FEM. Main results illustrated that a) the analytical results can describe the mechanical behavior of the compression process well and the recommended setting pressure was less than 40 MPa; b) with the materials hardened, the compression distance reduced smoothly and the maximum shear stress almost kept unchanged; c) the compression deformation and maximum shear stress rose significantly as the inner diameter of the open hole well increased; d) the height of the packer played a negative role both in maximum compression distance and maximum shear stress of the compression packer. In this paper, a novel analytical modeling of the pressure-bearing performance of compression packer was established. The HNBR specimens were manufactured and the mechanical property test was carried out. Besides, an analytical modeling of the compression distance and shear stress along the axial diameters on packer was established. The accuracy of analytical modeling was verified and the influence factors on pressure-bearing performance were discussed. [Display omitted] • A novel analytical model to calculate the distribution of compression distance and shear stress along the axial diameters was established. • The maximum shear stress inside rubber was proposed as evaluation criterion to judge the pressure-bearing performance. • The reliability and application range of analytical model was verified by FEM. [ABSTRACT FROM AUTHOR]