牙轮钻头耐高温扁平橡胶密封性能研究与应用

Research on Sealing Performance of High Temperature Resistant Flat Rubber for Roller Cone Bit

牙轮轴承常用金属密封不仅对振动敏感、密封力不足,而且制造成本高,占用空间大,密封件受力和变形不均匀。为此,研制了一种密封性能好且寿命长的新型高温牙轮钻头扁平橡胶密封圈。通过结构方案设计与HNBR、NBR两种材料的性能分析,以及HNBR本构参数的研究与确定,建立了密封圈三维瞬态热力耦合分析有限元模型,基于此模型对新型密封圈和O形圈的密封性能展开了数值模拟对比研究,将新型密封圈进行了现场应用并分析了使用效果。研究结果表明:在高温高转速工况下,新型橡胶密封圈较O形圈工作寿命更长;现场使用过的密封圈无严重损伤,仍可继续使用。研究结果可以为牙轮钻头高温密封件的设计及应用提供新思路。

Commonly used metal seals for roller cone bearings are not only sensitive to vibration with inferior sealing performance,but also have problems like high manufacturing cost,large space occupation and uneven stress and deformation of seals.Therefore,a new type flat rubber seal with good sealing performance and long life for high temperature roller cone bit has been developed.Through the structural design and the performance analysis of HNBR and NBR materials,as well as the research and determination of HNBR constitutive parameters,a three-dimensional transient thermal coupling analysis finite element model of the seal ring was established.Based on this model,comparative study on the sealing performance of the new type of seal ring and O-ring was carried out.The new type of sealing ring was applied in the field and the performance was analyzed.The research results show that:under the condition of high temperature and high RPM,the new type of rubber sealing ring has a longer working life than the O-ring.The new type of sealing ring used on site has no serious damage,which can be reused.The research can provide new ideas for the design and application of high-temperature seals for roller cone bits.