牙轮钻头径向非对称扁平密封性能研究

为了提高HAR橡胶密封圈寿命，提出一种新的径向非对称扁平密封结构。相比传统对称截面扁平密封圈，径向非对称截面的密封接触面积更小，因而减小了内圈动密封面旋转产生的热量以及磨损。通过试验对比氢化丁腈橡胶(HNBR)与丁腈橡胶（NBR）的性能，选择出合适的橡胶密封圈材料；分别建立径向非对称扁平密封圈与传统对称截面扁平密封圈的有限元模型，对比2种结构的密封性能；在不同的环境压力和温度下对径向非对称扁平密封圈的密封性能进行评价，并在现场进行应用验证。仿真结果表明：径向非对称扁平密封圈接触应力更大，密封性能更优；同时，其Mises应力明显低于传统对称截面扁平密封圈，证明径向非对称扁平密封更适合长期稳定工作。现场应用结果同样验证：在高温高压工况下，径向非对称扁平密封圈密封性能可靠，具有较高的实用价值。

Research of Radial Asymmetric Flat Seals of Cone Bit

In order to improve the service life of HAR rubber sealing rings,a new radial asymmetric flat sealing structure was proposed.Compared with the traditional symmetrical flat sealing ring,the radial asymmetric sealing contact area is smaller,thus reducing the heat and wear caused by the rotation of the inner ring moving sealing surface.By testing the properties of hydrogenated nitrile rubber (HNBR) and nitrile rubber (NBR),suitable rubber sealing ring materials were selected.The finite element models for radial asymmetric flat sealing rings and traditional symmetrical flat sealing ring were established,and the sealing performance of the two structures were compared.The sealing performance of radial asymmetric flat sealing rings was evaluated under different environmental pressures and temperatures,and on-site application verification was conducted.The simulation results show that the radial asymmetric flat sealing ring has higher contact stress and better sealing performance.Meanwhile,its Mises stress is significantly lower than that of traditional symmetrical flat sealing rings,proving that radial asymmetric flat sealing is more suitable for long-term stable operation.The on-site application results also verify that under high temperature and high pressure conditions,the sealing performance of the radial asymmetric flat sealing ring is reliable and has high practical value.