牙轮钻头滑动轴承仿生鲨鱼皮织构化表面润滑性能

牙轮钻头在超深井和大水平井的使用受到广泛关注，由于地层环境复杂化，为了使牙轮钻头有更高的稳定工作性。通过对合金材料表面织构化处理减摩效果的研究，结合鲨鱼皮减阻润滑的优势，针对牙轮钻头薄弱环节滑动轴承摩擦结合面进行了仿生鲨鱼皮织构化处理，基于所选取仿生织构的形貌参数构建滑动轴承流动润滑理论模型，采用有限差分法求解，获取润滑油的油压分布、承载能力及滑动轴承摩擦力，并探究阶跃冲击载荷下滑动轴承动压油膜的响应情况。结果表明：牙轮钻头滑动轴承流体润滑状态下，深径比大于0.3且面积率大于0.25的仿生表面织构对油膜承载力有增强效果；仿生表面织构在较低油膜压力下对油膜摩擦力影响突出，油膜摩擦力提高了14.12%;偏心率越大仿生表面织构对油膜承载力的提升效果越好，在偏心率为0.8时承载力提高效果达到200.45%;同时仿生织构的对滑动轴承流体润滑的轴向稳定性有提升效果。牙轮钻头滑动轴承仿生织构化处理有效地改善了滑动轴承润滑性能。可见，合适的织构尺寸能进一步提高滑动轴承处于流体润滑的适用工况范围，提高牙轮钻头的使用寿命。

Lubrication Properties of Bionic Shark Skin Textured Surface of Roller Bit Sliding Bearing

The use of roller cone bit in ultra-deep Wells and large horizontal Wells has been widely concerned. Due to the complex formation environment, roller cone bit has higher stability. Texture treatment on the surface of a alloy anti-friction effect research, combined with the advantage of sharkskin friction-reducing lubricating, in view of the roller bit weak link in the sliding bearing friction surface bionic shark skin texture, are chosen based on the morphology of bionic texture parameters to build the sliding bearing lubrication theory model, The finite difference method was used to obtain the oil pressure distribution of lubricating oil, bearing capacity and friction force of sliding bearing, and explore the response of dynamic pressure oil film of sliding bearing under step impact load. The results show that the bionic surface texture with depth to diameter ratio greater than 0.3 and area ratio greater than 0.25 can enhance the bearing capacity of oil film under the condition of fluid lubrication of roller bit sliding bearing. The bionic surface texture has a significant effect on the oil film friction at a lower oil film pressure, and the oil film friction increases by 14.12%. The higher the eccentricity is, the better the improvement effect of bionic surface texture on the bearing capacity of oil film is. When the eccentricity is 0.8, the improvement effect of bearing capacity is 200.45%. At the same time, the bionic texture can improve the axial stability of the fluid lubrication of the sliding bearing. The bionic texturing treatment of roller bit sliding bearing can effectively improve the lubrication performance of sliding bearing. It can be seen that the appropriate texture size can further improve the sliding bearing in the applicable working condition range of fluid lubrication, and improve the service life of roller bit.