连续管旋转接头密封性能及其影响因素分析

连续管旋转接头可实现高压动密封功能,该结构的密封元件由多个V型橡胶圈构成。连续管旋转接头密封性能不稳定、V型圈寿命低等问题制约了连续管正常作业,易出现重大安全隐患。采用有限元法,研究了V型橡胶圈材料性能、摩擦因数、工作介质压力等参数对密封性能的影响。研究结果表明:V型圈在介质压力作用下能够形成稳定可靠的密封; V型圈密封副的摩擦因数以及材料硬度对密封性能和摩擦磨损性能有显著影响,聚氨酯和丁腈橡胶材料硬度相同,均为85 HA或90 HA。适当降低密封副的摩擦因数,可提高V型橡胶圈的密封性能和摩擦磨损性能; V型橡胶圈在10 MPa以上介质压力作用下变形达到稳定,轴向压缩量在0.9～1.0 mm。研究成果可为连续管旋转接头方案设计提供一定的指导意义。

Analysis of Sealing Performance and Influencing Factors of Coiled Tubing Swivel Joint

The coiled tube swivel joint can realize the high-pressure dynamic sealing function, and the sealing element of this structure is composed of multiple V-shaped rubber rings packing. The unstable sealing performance of the coiled tubing swivel joint and the low service life of the V-ring packing restrict the normal operation of the coiled tubing and are prone to major safety hazards in the engineering operation. The impact of the material properties, friction coefficients, medium pressure, and other parameters of the V-ring packing sealing performance was studied by using the finite element method. The results show that the V-ring packing can achieve a stable and reliable seal under the action of the medium pressure, the friction coefficient, and the material hardness have a significant effect on the sealing performance and friction wear performance. The Polyurethane and nitrile rubber materials have the same hardness, both 85 HA and 90 HA. When the friction coefficient of the sealing pair is as low as possible, the sealing performance and friction and wear performance of the V-shaped rubber ring packing are better. The deformation of the V-shaped rubber ring packing is stable under the medium pressure above 10 MPa, and the axial compression is 0.9 to 1.0 mm. The research results can provide certain guiding significance for the design of coiled tubing swivel joints.