Friction Forces in O-ring Sealing

In the present study the focus was on developing a relationship as practical and convenient option for computing the friction force in O-ring sealing elements as used in the hydraulic and pneumatic equipments. For low-pressure applications, the developed relationship was applied for a different number of O-ring diameters, by investigating the obtained results, a good agreement has been observed for some of the tested diameters through the comparison between the obtained results from the developed relationship with those experimentally measured, which ensures the validity of the relationship. Regarding the low-pressure applications, theoretical and experimental studies were carried out in order to evaluate the effect of most important working parameters and conditions on the friction behavior. A remarkable advantage of using the relationship that reveals the accuracy of the relationship was detected through the comparison between the computed results with those obtained from the friction characteristic curves. Because the developed relationship having more important and quantified working parameters, it gives more accurate results, while in the characteristic tests curves the working parameters cannot be quantified, because they overlap and then they act cumulatively. The experimental study was performed and the obtained results are presented for two working cases, in which the friction force was determined in absence of pressurized fluid as in the first case, while in the second case the friction force was determined on basis of the presence of a pressurized fluid`s.