The friction characteristic of the pneumatic cylinder is influenced by many different working factors, including the climate environment. The climatic environment has two characteristic factors: temperature (T) and relative humidity (RH), varying by season and geographic region. Therefore, variations in velocity and climatic specific factors will change the friction characteristic of pneumatic cylinder. This paper presents the results of research on the simultaneous effects of the velocity, temperature and relative humidity of the humid monsoon tropical climate in Vietnam on the static friction properties of pneumatic cylinder. According to the experimental plan, the studies are conducted on the industrial pneumatic cylinder with three input factors: velocity v: 30 ÷ 100mm/s, temperature T: 150 C ÷ 490 C and relative humidity RH: 51% ÷ 99%, with the target function being static friction (FS). The results have determined the static friction model of a pneumatic cylinder, shown through empirical regression equations with exponential form, describing the variation of the static friction Fs depending on three research factors simultaneously (v, T, RH). The numerical simulation also shows that Fs static friction force decreases as T, RH increases and increases with the velocity. The influence of velocity is most significant, and the influence of air relative humidity is stronger than the temperature on static friction force.

Keywords: Friction force, pneumatic cylinder, characteristic, humid tropical climate