牙轮钻头空心滚滑复合轴承的设计  

A hollow roller composite bearing designed for cone bits

作　　者：韩传军[1] 张杰[1] 蒋光强[2] 林发权[2] 

机构地区：[1]西南石油大学机电工程学院 [2]中国石油塔里木油田公司工程技术部

出　　处：《天然气工业》2013年第3期53-58,共6页Natural Gas Industry

基　　金：国家自然科学基金“复杂工况井高速重载牙轮钻头轴承边界润滑及损伤机理研究”(编号:51004083);中国博士后科学基金“重载牙轮钻头轴承偏磨机理及修形技术研究”(编号:20100481384)资助

摘　　要：轴承是牙轮钻头的重要组成部分,它的失效直接影响着整个钻头的使用寿命。为此,分析了牙轮钻头用滑动轴承、滚动轴承及浮动套轴承的研究现状,在综合3种轴承各自优势的基础上,最终设计出了空心滚滑复合轴承和有孔浮动套滚滑轴承:①空心结构的滚滑体较实心结构的滚滑体提供了更多的贮存润滑油空间,使牙轮转动过程中滚滑体的各接触面之间的润滑性能得以改善;②空心结构增大了滚滑体的散热面积,自由流动的润滑油通过对流散热方式冷却轴承各个转动的部件。同时,建立了滚滑轴承的有限元分析模型,进行了实心和空心结构滚滑轴承的等效应力与接触应力分析。结果表明:空心滚滑复合轴承比实心结构的承载能力更强,滚滑体的应力分布也更为均匀,降低了由局部应力过大或温度过高而导致整个轴承失效的概率,有利于提高牙轮钻头的使用寿命。最后,建议空心滚子的空心度在50%～70%,滑块的空心度不宜超过60%。The bearing is such an important part of a cone bit that its failure will bring about a negative effect on the service life of the bit system. Therefore, an analysis was conducted in this paper to review the latest research findings on three bearing types for cone bits： sliding hearing, roiling bearing, and floating bush bearing, the respective advantages of which were thus integrated into the fi- nal design of a hollow roller composite bearing and a perforated floating bush roller bearing. Compared to a solid roller structure, this hollow roller structure provides more storage room for lubricant oil, thereby improving lubrication between the contact surfaces of the rollers during cone rotation; and also increases the cooling area of the rollers so that the lubricant could flow freely to cool the rolling elements by thermal convection. Furthermore, a finite element analysis model was estabiished to conduct a comparative analy- sis of equivalent stress and contact stress for the solid and hollow roller bearings. Results proved that the hollow roller composite bearing has a greater carrying capacity and a more even stress distribution is found on its roller block. As a result, the failure proba- bility of the bearing system resulting from local overstress or over-heat is therefore reduced to contribute to a longer service life of cone bits. Finally, it is recommended that the optimum hollow ratio range of the hollow roller should be 50 - 70G and that of the sliding block should not be less than 60~.

关 键 词：牙轮钻头 空心 滚滑轴承 结构设计 应力 轴承失效 钻头寿命 

分 类 号：TE921[石油与天然气工程—石油机械设备]