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Abstract
There is a serious face contact friction on dry gas seal ring face when it is in the start-up phase and abnormal operation, therefore, to analyze and discuss the tribology performance, the tribological test is necessary for dry gas seal dynamic and static ring. The dynamic and static spiral groove dry gas seal ring was tested to study the tribology performance under different operating mode by using the friction and wear tester with selected reasonable test conditions and the corresponding testing technology. The results of the test indicated that there was the obvious running-in phenomenon for spiral groove dry gas seal face in the special condition test. Moreover, the tribology performance of the face was changed with the test. Besides, when the rotational speed and load increased from 150 r·min⁻¹ and 226 N to 500 r·min⁻¹ and 1130 N, the wear mass loss of graphite ring was increased by 193.3% but the friction coefficient was decreased 22.3%. This showed that the self-lubrication of graphite ring affected the friction state of the seal face. Because the spiral groove end face contact was different from the smooth surface, the inner ring was more wear than outer ring of the graphite ring. The test results provided a basis for tribological performance optimization of the spiral groove dry gas seal face.
... The study revealed that the end face groove structure of the hydrodynamic seal affects the opening performance, with the groove dam ratio having the most significant impact. An increase in the groove dam ratio was found to enhance the opening performance [8][9][10][11]. ...
To investigate the degradation mechanism of the opening performance of hydrodynamic seals during multiple start-ups, a model was proposed to analyze the wear characteristics during the start-up process, and an experimental study was conducted. It has been discovered that the state evolution of the hydrodynamic seal during the single start-up process occurs in five stages. The main factor that influences the deterioration of the initial performance of hydrodynamic seals during multiple start-ups is the decrease in the depth of the root groove. To prevent the deterioration of the initial performance of the hydrodynamic seal, it is essential to minimize processing errors in groove depth and reduce the residence time during the mid-speed and mid-load stages of the starting process.
... However, the theoretical analysis can't accurately reflect the actual friction state between the end faces. In recent years, Ding et al has experimently investigated the frictional performance of smooth rings used in dry gas seals, and examined the tribological characteristics under different working conditions [18][19][20][21] . ...
The friction performances of the end face in dry gas seals with spiral grooves were investigated. In the meantime, the influence of the spiral groove structural parameters on friction performance was revealed under dry frictional conditions. Hard-hard friction pairs consisting of SiC end faces with spiral grooves and DLC (Diamond like Carbon) micro-textured sealing ring end faces were chosen as the research subjects. Dry friction tests were conducted using a HDM20 end face friction and wear testing machine on spiral groove dry gas sealing rings with spiral angles of 16° and 18°. By analyzing the variations in friction temperature and friction coefficient, the friction mechanisms of the sealing rings and the impact of the spiral angle on end face friction performance were examined. The results proposed that the 18° spiral groove end face exhibits slightly lower friction temperature and friction coefficient compared to the 16° spiral groove end face, indicating a more pronounced reduction in wear and smoother operation of the friction pair. The findings of this study provide a basis for understanding the frictional characteristics of sealing ring end faces and optimizing groove structures.
... Moreover, different preparation methods can result in great differences in the tribological properties of DLC films [16,17]. Ding et al. [18,19] analyzed the effect of different spiral grooves on the dry air seal friction coefficient. Some of the DLC coatings are able to afford friction coefficients of down to 0.01 under oil-lubricated sliding conditions [20,21]. ...
After applying the diamond-like carbon (DLC) coating and surface micro-texturing into dry gas seal, the friction performance of textured surface DLC film of high pressure dry gas sealing ring has been researched in this paper. Firstly, the variation curves of friction coefficient with different load, rotation speed, and micro-texture geometric parameters are measured by using end-face friction and wear experiment machine (HDM20) under dry friction condition. Secondly, in order to compare the wear condition, the surface morphology of pretest and posttest is analyzed by using three-dimensional non-contact surface topography instrument (ST400). The experiment results show that: (1) The seal face which exists micro-textured DLC film has low friction coefficient, (2) under the same condition of micro-textured parameters, the friction coefficient would decrease with the increase in the load and would decrease firstly and then increase with the increase in the rotation speed, and (3) under the same running condition, the friction coefficient would decrease with the diameter of micro-pit and would increase with the increase in the density of textured area; however, the changing degree of friction coefficient would decrease. The experiment results could provide foundation for researching the tribological characteristics of faces of dry gas seal and optimizing the micro-textured structure.
Parallel groove surface textures with different area densities were fabricated on ASTM 1045 steel. Friction tests were conducted under dry sliding condition. Temperature rise, friction coefficient and wear of both the textured and untextured specimens were studied. An embedded K-type thermocouple beneath the friction surfaces was employed to measure frictional temperature rise. The results indicated that the temperature rise of the textured specimen was obviously reduced compared with that of the untextured specimen, although the difference between the friction coefficients was not significant. The specimen with high texture density exhibited a small temperature rise. The difference in temperature rise between the specimens with different texture densities can be primarily attributed to differences in heat dissipation and energy allocation between the tribo-pairs caused by the textured structure. The energy consumed by wear and plastic deformation was small in comparison with the total energy input by friction, thus, the influence of these factors on temperature rise can be considered to be negligible. © 2015 Science China Press and Springer-Verlag Berlin Heidelberg