Main motor grease composition and a bearing for the bearing of a railway vehicle

摘要

PROBLEM TO BE SOLVED: To provide a grease composition for a main electric motor shaft bearing of a railway vehicle, which has excellent heat resistance and a long bearing lubrication life.SOLUTION: The grease composition for a main electric motor shaft bearing of a railway vehicle includes: (a) a thickener including a hydroxy fatty acid with a carbon number of 12 to 24 having one or a plurality of hydroxyl groups and a lithium salt of fatty acid or dicarboxylic acid with a carbon number of 2 to 12; (b) base oil including an oil with a kinematic viscosity at 40°C of 300 to 500 mm/s, an oil with a kinematic viscosity at 40°C of 80 to 300 mm/s, and an oil with a kinematic viscosity at 40°C of 20 to 80 mm/s, which has a kinematic viscosity at 40°C of 80 to 200 mm/s; (c) an amine-based antioxidant; and (d) a hindered phenolic antioxidant.