Industrial Gear Oils Imparting Reduced Gearbox Operating Temperatures

Abstract

The invention relates to improved industrial gear oil compositions that substantially reduce the operating temperature of a gearbox in which the gear oil compositions are used. The reduced operating temperature provided by the described compositions leads to improved equipment performance. The invention also relates to methods of making the described industrial gear oil compositions and methods of using the same.

1 . An industrial gear composition comprising:
 (a) an oil of lubricating viscosity;   (b) an industrial gear lubricant additive package; and   (c) a fatty phosphite present at no less than 1.0 percent by weight of the overall composition.   
     
     
         2 . The composition of  claim 1  wherein components (b) and (c) are present in amounts such that the weight ratio of component (b) to component (c) is from 4:1 to 1:5. 
     
     
         3 . The composition of  claim 1  wherein component (a), the oil of lubricating viscosity, comprises a group I base oil, a group II base oil, a group III base oil, a synthetic base oil, of any combination thereof. 
     
     
         4 . The composition of  claim 3  wherein component (b), the industrial gear lubricant additive package, comprises one or more antiwear additives and/or extreme pressure agents, one or more rust and/or corrosion inhibitors, one or more foam inhibitors, one or more demulsifiers, or any combination thereof. 
     
     
         5 . The composition of  claim 4  wherein component (b), the industrial gear lubricant additive package, further comprises one or more friction modifiers. 
     
     
         6 . The composition of  claim 1  wherein component (b), the industrial gear lubricant additive package, comprises: one or more sulfurized olefins; one or more polysulfides; one or more phosphorus amine salts; one or more thiophosphate esters, one or more thiadiazoles, tolyltriazoles, polyethers, and/or alkenyl amines; one or more ester copolymers; one or more carboxylic esters; one or more succinimide dispersants, or any combination thereof. 
     
     
         7 . The composition of  claim 1  wherein component (c), the fatty phosphite, comprises an alkenyl phosphite or esters thereof. 
     
     
         8 . The composition of  claim 1  wherein the composition is an industrial gear additive concentrate containing up to 40 percent by weight of component (a). 
     
     
         9 . The composition of  claim 1  wherein the composition is an industrial gear lubricant containing at least 80 percent by weight of component (a). 
     
     
         10 . The composition of  claim 9  wherein component (b) is present from 1 to 5 percent by weight of the overall industrial gear lubricant; and
 wherein component (c) is present from 1.0 to 10.0 percent by weight of the overall industrial gear lubricant. 
 
     
     
         11 . A method of reducing the operating temperature of an industrial gearbox, said method comprising the steps of: (I) adding to an industrial gear oil lubricant a fatty phosphite such that the lubricant contains at least 1.0 percent by weight fatty phosphite, and (II) operating the industrial gearbox while supplying the industrial gear oil lubricant to the industrial gearbox. 
     
     
         12 . The method of  claim 11  wherein at least a portion of the fatty phosphite is added to the industrial gear oil lubricant before the lubricant is supplied to the industrial gearbox, or wherein at least a portion of the fatty phosphite is added to the industrial gear oil lubricant after the lubricant is supplied to the industrial gearbox. 
     
     
         13 . The method of  claim 11  wherein an industrial gear lubricant additive package and the fatty phosphite and are present in amounts such that the weight ratio of additive package to fatty phosphite is from 4:1 to 1:5. 
     
     
         14 . The method of  claim 11  wherein component (a), an oil of lubricating viscosity, comprises a group I base oil, a group II base oil, a group III base oil, a synthetic base oil, of any combination thereof. 
     
     
         15 . The method of  claim 11  wherein the industrial gear lubricant additive package, comprises one or more antiwear additives and/or extreme pressure agents, one or more rust and/or corrosion inhibitors, one or more foam inhibitors, one or more demulsifiers, or any combination thereof. 
     
     
         16 . The method of  claim 14  wherein component (b), the industrial gear lubricant additive package, comprises: one or more sulfurized olefins; one or more phosphorus amine salts; one or more thiophosphate esters, one or more thiadiazoles, tolyltriazoles, polyethers, and/or alkenyl amines; one or more ester copolymers; one or more carboxylic esters; one or more succinimide dispersants; or any combination thereof. 
     
     
         17 . The method of  claim 13  wherein component (c), the fatty phosphite comprises an alkenyl phosphite or esters thereof. 
     
     
         18 . The method of  claim 11  wherein the composition is an industrial gear additive concentrate containing up to 40 percent by weight of the oil of lubricating viscosity. 
     
     
         19 . The method of  claim 11  wherein the composition is an industrial gear lubricant containing at least 80 percent by weight of the oil of lubricating viscosity. 
     
     
         20 . The method of  claim 19  wherein the additive package is present from 1 to 5 percent by weight of the overall industrial gear lubricant; and
 wherein the fatty phosphite is present from 1.0 to 10.0 percent by weight of the overall industrial gear lubricant.