UDC 621.7; 621.8; 539.4
Introduction. Therefore, elucidating of the wear in the rolling considering slip is an important task for improving the durability of tribotechnical characteristics of contacting surfaces, such as a friction pair «cable block – rope».
Research methodology. Tests are conducted in accordance with DIN 50324, ASTM G99 «Standard Test Method for wear Testing with a Pin-on-Disk Apparatus», as well as standards ASTM G 133, ASTM D 3702, ASTM D 5183, ASTM D 4172 and ASTM D 2266.
The tests of the samples being rolled with the slip were conducted on a wear machine MI the top shaft of which was able to rotate, and was returned about a vertical axis at an angle of 5°, which provided lateral slip about 10% of that observed in the friction pair «cable block – rope». To measure the wear weight loss of samples used VLR – 200.
The results. Found that wear actually depends on the load, but depends only on the slip.
In the case of rolling with longitudinal slip, equal to 10% of the friction surface become brown color, typical of oxidative deterioration. When cross-slip surface layer due to lateral plastic flow continuously updated. In longitudinal slip surface areas and products of wear, moving along the circle skating, interact repeatedly, increasing the role of corrosion during wear. Speed oxidative deterioration was dependent on the hardness of steel, so the impact of hardness on the results of experiments with longitudinal slip offset that should be considered when analyzing the results of a wear machine MI.
Thus, one could argue that the slip to 10% speed deterioration is almost independent of pressure or even decreases with its increase.
When changing operating conditions tribosystem wear rate may change abruptly, thus changing the surface friction type, size, color and chemical composition of the products of friction, that is a result of the transition from one mechanism to the second wear.
Boundary layers of bodies or surface film, with their contact during the rolling of the sliding friction coefficient reduce to 3 – 4 times and thus the speed and intensity of wear. Therefore, by changing the coefficient of friction may establish a process erase surface films.
Conclusions. Surface roughness effect on friction coefficient of friction and wear rate when rolling with slip, i.e. with decreasing surface roughness decreases.
If the slip is up to 2% it is seen as a sharp change in friction can be observed, after which it remains practically unchanged through the distribution of slip on the entire area of contact.
Key words: pair of friction, slipping, rolling motion, crumpling, coefficient of friction, rolling-off by a roller.