Grease, rolling bearing, constant velocity joint, and rolling parts

Abstract

The present invention provides grease which prevents frictional wear on a lubricating surface and excellent in performance of preventing occurrence of flaking, heat-resistant performance, and long-term durability, a grease-enclosed rolling bearing, a constant velocity joint, and rolling parts. Grease is composed of base grease, essentially containing a thickener, to which at least 0.01 to 15 wt % of one substance selected from among bismuth and inorganic bismuth compounds is added. The inorganic bismuth compounds are at least one inorganic bismuth selected from among bismuth sulfate, bismuth trioxide, bismuth carbonate, and sodium bismuthate. The above-described grease is used for the rolling bearing and the constant velocity joint. A coating film of at least one substance selected from among the bismuth and the inorganic bismuth is formed on surfaces of the rolling parts.

1 - 22 . (canceled) 
     
     
         23 . A grease for use in a rolling bearing comprising a base grease and an additive, wherein the base grease comprises a base oil and a thickener, said base oil is one oil selected from among poly-α-olefin oil, mineral oil, and ether oil, said base oil having a kinematic viscosity of 33-100= 2 /s at 40° C. and the additive comprises bismuth powder having a diameter of 5-500 μm. 
     
     
         24 . The grease according to  claim 23 , wherein 0.01 to 15 wt % of the bismuth powder is added to a total amount of said base grease and said additive. 
     
     
         25 . The grease according to  claim 23 , wherein said thickener is at least one compound selected from among urea-based compounds and lithium soap. 
     
     
         26 . The grease according to  claim 23  wherein said base oil is a poly-α-olefin oil. 
     
     
         27 . The grease according to  claim 23  wherein said base oil is a mineral oil. 
     
     
         28 . The grease according to  claim 23  wherein said base oil is an ether oil. 
     
     
         29 . The grease according to  claim 23 , wherein said bearing is for use in a rolling stock.