关键词: 干气密封, DLC薄膜, 螺旋角, 界面法向力, 摩擦性能

Abstract: In the case of low speed and high pressure, the wear of dry gas seal is more serious, therefore, the preparation of DLC film by static ring is proposed, and the friction characteristics of the end face of the static and dynamic ring are analyzed with the groove structure. The dry gas seal with different spiral angle was tested by friction and wear machine, and the change law of temperature rise, friction coefficient and surface wear morphology were tested. The test results show that with the increase of load and speed, the friction temperature rises, friction coefficient and grinding mark of 16° spiral angle are less than 18°. Under the same working condition, the value of average friction coefficient of 18°spiral angle is 0.02 larger than that of 16°spiral angle, and the average friction temperature is increased by 5 ℃. On the one hand, because of the different spiral angle, the interface method is different and the wear degree of the end face of 18° spiral angle is greater than 16° spiral angle. On the other hand, with the increase of load and speed, the graphitization degree of DLC films is increased, which shows DLC films and spiral groove play a key role in the friction and wear of end faces. At the same time, it is found that the wear degree of the two kinds of spiral angle inner ring is greater than the outer ring, so the spiral groove can reduce the wear degree of the end face. The test results laid a foundation for the optimization design and practical application of spiral groove dry gas seal.

Key words: Dry gas seal, DLC film, Spiral groove, Interfacial normal force, Friction property