毕业论文牙轮钻头动密封结构设计与分析.docVIP

摘 要 随着材料研究以及钻头设计技术的不断进步，PDC钻头对地层的适应范围越来越宽，只要地层适宜，PDC（聚晶金刚石复合片）钻头应是深井段钻头的较好选择。然而面对深部井段恶劣的钻井条件尤其是软硬频繁交错、岩性不连续分布的泥砾岩地层，PDC钻头往往难以适应，所以牙轮钻头仍是深部地层钻井中的重要开采工具。高耐磨、高韧性的牙齿和长寿命钻头轴承一直是牙轮钻头研究的重点。牙齿技术的关键在于材料，轴承技术的关键在于密封，本课题重点研究轴承的密封系统。普通牙轮钻头轴承密封结构的补偿环组件，需要用弹性体的辅助密封圈，阻塞补偿环组件与轴之间的间隙，保证该处不会泄漏。同时还要保证补偿环组件在轴上转动能力。这两者常常矛盾，如果密封圈的压缩量不足必然泄漏，因此需要密封圈的压缩量大一些；而压缩量过大，滑动摩擦阻尼随之迅速增大。此时，弹性很好的材料都无法避免补偿环既要在轴上转动，又要依靠过盈量来阻塞介质泄漏的矛盾。同时由于辅助密封圈材料的老化、溶涨、绕曲、过渡挤压、沉淀颗粒堵塞等，都会阻碍补偿环在轴向上滑动影响追随性，造成密封失效。针对这一问题的研究，结合牙轮钻头轴承密封的实际工况和尺寸参数，充分利用波纹管机械密封的耐高温、防震动优势，对钻头轴承密封的结构进行改进设计，同时对密封的润滑补偿系统进行优化设计。 关键词：牙轮钻头；动密封；波纹管；润滑补偿系统 Abstract As the technology that ,the research of materials and the design of drill bit ,advances ,the scope of work of PDC(Polycrystalline Diamond Compact ) bit becomes more and more wide.As long as the stratum is appropriate ,PDC bit should be a good choice for drilling deep well.As far as deep well, face with the terrible drilling conditions especially for the hard and soft frequent crisscross, lithology discontinuous distribution of mud conglomerate stratum ,PDC bit always has difficulties to adapt, so cone bit is still indispensable drilling tools for deep well.High wear-resisting, high toughness teeth and longevity bit bearing has been the focus of research of cone bit. The key lies in the teeth technology is material, and the key lies in bearing technology is seal, the key subject of the research is bearing sealing systems. The compensation loop components of general cone bit bearing seal structure , need to use the elastomer auxiliary sealing ring, and block the gap between compensation loop and shaft , ensure it wont leak.At the same time,it ensures the rotation ability of compensation ring .The two sides always become contradictory ,that if sealing ring compression is not enough to inevitable leakage, therefore need to sealing ring enough big ;But compression is too large, sliding friction damping relatively increases rapidly. At this time , excellent elastic materials can not avoid the conflict