Proposal of Field Life Design Method for Wet Multiple Plate Clutches of Automatic Transmission on Forklift-trucks

A method of life calculation for wet multiple-plate clutches has not been established; they are tribological parts and the damage of such parts depends on many intertwining parameters such as operating condition and lubrication condition. The focus of this study is on the clutch plate surface temperature, T, that represents many parameters. A T-N curve was developed for the friction material that is similar to the S-N curve for metal fatigue. Load frequency was measured from actual operating conditions in the field, and from this data the frequency of T was predicted. Field life could then be calculated for wet multiple plate clutches from the aforementioned T-N curve, the field frequency of T, and Miner's law.