Development of High Performance Grease for Traction Motor Bearing Application

摘要

Traction Motors are being used to transmit power to wheels through Traction Motors gears - pinion / wheel . To support the armature , its shaft rests on commutator and pinion end bearings and therefore the lubrication of these bearings is very important for smooth functioning of Locomotives . Unlike gearbox bearings, Traction Motor bearings are usually grease lubricated which avoids the complex oil lubrication system & risk of oil entering in to the motor. These Traction Motors are being mounted on Locomotives which are usually subjected to severe operating conditions like high speed, heavy loads, high temperatures and high rpm. Therefore conventionally used greases fail to perform satisfactorily and special greases are being developed to cope with these problems. Indian railways, the premier transport system of India, is the largest rail network in Asia and second largest in the world under one management. Conventionally Lithium base grease formulated in mineral oil are being used in this application. However, due to increase in speed & loads, it is preferable to use high performance greases for satisfactory extended lubrication. In view of this, Indian Oil R&D Centre has developed a Lithium grease with high drop point embodied with unique combination of additives suitable, specially for high speed Traction motor bearing used in Diesel Locomotives of Indian Railways. This new grease was field tried in WDM2 locomotives of Indian Railways. Trials were periodically monitored and used grease samples were analysed. Based on the analysis the periodicity of the re-lubrication was extended. After three years of long trials, used grease samples were analysed and found that Indian Oil developed grease has performed satisfactorily to lubricate the bearing for three years. In this paper physico-chemical data of this new grease, used grease analysis data, field performance has been discussed in detail.