Equivalent Calculate of the Equivalent Radius and the Tribological Performance of the Marine Water-Lubricated Bearing

The friction and wear properties of water-lubricated stern bearing are one of the main influencing factors of the working performance of the marine. It is of great significance to the performance evaluation of the water-lubricated stern bearing on the reasonable predicting their friction coefficient during the working process. Nowadays, the theoretical calculation formula has been established. However, the practicability of the formula was poor because the equivalent radius could not be obtained effectively under the pin-plate test condition. In this case, the friction mechanisms of water-lubricated stern bearing were summarized under the condition of boundary lubrication.In order to summarize the formula to the equivalent parameter of equivalent radius and verify the calculation formula of the friction coefficient, a large number of experiments were conducted on a CBZ-1 tester. The result show that: (a) The calculation formulas of the equivalent radius was reasonable with high accuracy fits based on the theoretical calculation formula of the friction coefficient.(b) The difference between the theoretical and the actual of friction coefficient for the tested materials was small, and it provided the theoretical and experimental basis for studying the tribological performance of the same type material. (c) The friction sources of the water lubricated stern bearings in the process of work can be divided into hysteresis friction, furrow friction and adhesion friction. The hysteresis friction was the main source of the friction under boundary lubrication. This study provided an experimental basis for the engineering application of water-lubricated stern bearing on the equivalent parameter of the equivalent radius under the pin-plate test condition.