Method for lubricating heavy duty geared apparatus

Abstract

A method for improving the oil drain interval, fuel and energy efficiency of heavy duty geared machinery by lubricating said apparatus using a lubricating oil composition comprising as base oil about 20 to 75 wt % PAO 2 to 10, about 5 to 40 wt % PAO 150-1000, about 10 to 40 wt % PAO 20-100, about 5 to 20 wt % of one or more polyol ester or dibasic acid ester having a kinematic viscosity of between about 2 to 5 mm 2 /s at 100° C. mm 2 /s and further containing an effective amount of at least one gear oil additive, said lubricating oil composition having a kinematic viscosity at 100° C. between 9 and 12.5 mm 2 /s, and exhibiting a traction coefficient value ( 100 °C./30 SSR value) of 0.0197 or less, a Brookfield viscosity at −40° C. of about 26,000 cP or less a CCS viscosity at −25° C. of 4200 cP or less, a flash point of 220° C. or higher and a NOACK volatility of 15% or less.

1 . A method for improving the fuel economy and energy efficiency of heavy duty geared machinery operated under high load conditions comprising running the heavy duty geared machinery under high load conditions while lubricating said machinery by using a lubricating oil composition comprising from about 20 to 75 wt % of a polyalphaolefin fluid having a kinematic viscosity at 100° C. of between about 2 to 10 mm 2 /s, about 5 to 40 wt % of a polyalpha- olefin fluid having a kinematic viscosity at 100° C. of between about 150 to 3,000 mm 2 /s, about 10 to 40 wt % of a polyalphaolefin fluid having a kinematic viscosity at 100° C. of between about 20 to 100 mm 2 /s, about 5 to 20 wt % of one or more polyolesters or diesters having a kinematic viscosity at 100° C. of between about 2 to 5 mm 2 /s and a pour point of at least −25° C., and further containing at least one gear oil performance additive, said lubricating oil composition being characterized by having a kinematic viscosity at 100° C. of between 9 and 12.5 mm 2/s and exhibiting a traction coeffluent value, measured as the 16N/100° C./30 SSR value, of about 0.0197 or less, a Brookfield viscosity at −40° C. of about 26,000 cP or less, and a CCS viscosity at −25° C. of about 4200 cP or less, a flash point of 220° C. or higher and a NOACK volatility of 15% or less. 
     
     
         2 . The method of  claim 1  wherein the lubricating oil composition comprises about 30 to 60 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 3.5 to 8 mm 2/s, about 5 to 20 wt % of a PAO fluid having a kinematic viscosity of between about 150 to 1500 mm 2 /s, about 15 to 30 wt % of a PAO fluid having a kinematic at 100° C. of between about 20 to 80 mm 2 /s, about 5 to 15 wt % of an ester having a kinematic viscosity at 100° C. of between about 2 to 4.5 mm 2/s and further containing at least one gear oil performance additive. 
     
     
         3 . The method of  claim 1  wherein the lubricating oil composition comprises about 30 to 60 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 2 to 10 mm 2 /s. 
     
     
         4 . The method of  claim 1  wherein the lubricating oil composition comprises about 5 to 20 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 150 to 3000 mm 2 /s. 
     
     
         5 . The method of  claim 1  wherein the lubricating oil composition comprises about 15 to 30 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 20 to 100 mm 2 /s. 
     
     
         6 . The method of  claim 1  wherein the ester comprises about 5 to 15 wt % of the lubricating oil and has a kinematic viscosity at 100° C. of between about 2 to 4.5 mm 2 /s. 
     
     
         7 . The method of  claim 1 ,  2 ,  3 ,  4 ,  5  or  6  wherein the lubricating oil composition comprises about 45-55 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 3.5 to 6 mm 2/s, about 8 to 12 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 150 to 500 mm 2 /s, about 18 to 22 wt % of a PAO fluid having a kinematic viscosity between about 20 to 60 mm 2 /s. 
     
     
         8 . The method of  claim 7  wherein the ester is a non-polyol ester. 
     
     
         9 . The method of  claim 8  wherein the non-polyol ester comprises about 5 to 15 wt % of the lubricating oil and has a kinematic viscosity at 100° C. of between about 2.5 to 4.5 mm 2 /s. 
     
     
         10 . The method of  claim 1 ,  2 ,  3 ,  4 ,  5  or  6  wherein the lubricating oil composition is characterized by exhibiting a traction coefficient value measured as the 16N/100° C./30 SSR value of about 0.0191 or less. 
     
     
         11 . The method of  claim 1 ,  2 ,  3 ,  4 ,  5  or  6  wherein the lubricating oil composition is characterized by exhibiting a Brookfield viscosity at −40° C. of about 21,000 cP or less, a flash point of 230° C. or higher and a NOACK volatility of 15% or less. 
     
     
         12 . The method  claim 1 ,  2 ,  3 ,  4 ,  5  or  6  wherein the lubricating oil composition is characterized by exhibiting a CCS viscosity at −25° C. of about 3,600 cP or less. 
     
     
         13 . The method of  claim 1 ,  2 ,  3 ,  4 ,  5  or  6  wherein the lubricating oil composition is characterized by exhibiting a CCS viscosity at −25° C. of about 3400 cP or less. 
     
     
         14 . The method of  claim 7  wherein the lubricating oil composition is characterized by exhibiting a traction coefficient value measured as the 16N/100° C./30 SSR value of about 0.0191 or less, a Brookfield viscosity at −40° C. of about 21,000 cP or less and a CCS viscosity at −25° C. of about 3600 cP or less, a flash point of 230° C. or less and a NOACK volatility of 13% or less. 
     
     
         15 . The method of  claim 14  wherein the ester comprises about 5 to 15 wt % of the lubricating oil and has a kinematic viscosity at 100° C. of between about 2.5 to 4.5 mm 2 /s. 
     
     
         16 . The method of  claim 9  wherein the ester comprises about 8 to 12 wt % of the lubricating oil and has a kinematic viscosity at 100° C. of between about 2.5 to 4.5 mm 2 /s. 
     
     
         17 . The method of  claim 1 ,  2 ,  3 ,  4 ,  5  or  6  wherein the lubricating oil composition is characterized by the absence of viscosity index improvers. 
     
     
         18 . A lubricating oil composition comprising from about 20 to 75 wt % of a polyalphaolefin fluid having a kinematic viscosity at 100° C. of between about 2 to 10 mm 2 /s, about 5 to 40 wt % of a polyalphaolefin fluid having a kinematic viscosity at 100° C. of between about 150 to 3,000 mm 2/s, about 10 to 40 wt % of a polyalphaolefin fluid having a kinematic viscosity at 100° C. of between about 20 to 100 mm 2 /s, about 5 to 20 wt % of one or more polyolesters or diesters having a kinematic viscosity at 100° C. of between about 2 to 5 mm 2 /s and a pour point of at least −25° C., and further containing at least one gear oil performance additive, said lubricating oil composition being characterized by having a kinematic viscosity at 100° C. of between 9 and 12.5 mm 2 /s and exhibiting a traction coeffluent value, measured as the 16N/100° C./30 SSR value, of about 0.0197 or less, a Brookfield viscosity at −40° C. of about 26,000 cP or less, and a CCS viscosity at −25° C. of about 4200 cP or less, a flash point of 220° C. or higher and a NOACK volatility of 15% or less. 
     
     
         19 . The lubricating oil composition of  claim 18  wherein the lubricating oil composition comprises about 30 to 60 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 3.5 to 8 mm 2 /s, about 5 to 20 wt % of a PAO fluid having a kinematic viscosity of between about 150 to 1500 mm 2 /s, about 15 to 30 wt % of a PAO fluid having a kinematic at 100° C. of between about 20 to 80 mm 2 /s, about 5 to 15 wt % of an ester having a kinematic viscosity at 100° C. of between about 2 to 4.5 mm 2 /s and further containing at least one gear oil performance additive. 
     
     
         20 . The lubricating oil composition of  claim 18  wherein the lubricating oil composition comprises about 30 to 60 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 2 to 10 mm 2 /s. 
     
     
         21 . The lubricating oil composition of  claim 18  wherein the lubricating oil composition comprises about 5 to 20 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 150 to 3000 mm 2 /s. 
     
     
         22 . The lubricating oil composition of  claim 18  wherein the lubricating oil composition comprises about 15 to 30 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 20 to 100 mm2/s. 
     
     
         23 . The lubricating oil composition of  claim 18  wherein the ester comprises about 5 to 15 wt % of the lubricating oil and has a kinematic viscosity at 100° C. of between about 2 to 4.5 mm 2 /s. 
     
     
         24 . The lubricating oil composition of  claim 18 ,  19 ,  20 ,  21 ,  22  or  23  wherein the lubricating oil composition comprises about 45-55 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 3.5 to 6 mm 2 /s, about 8 to 12 wt % of a PAO fluid having a kinematic viscosity at 100° C. of between about 150 to 500 mm 2 /s, about 18 to 22 wt % of a PAO fluid having a kinematic viscosity between about 20 to 60 mm 2 /s. 
     
     
         25 . The lubricating oil composition of  claim 24  wherein the ester is a non-polyol ester. 
     
     
         26 . The lubricating oil composition of  claim 25  wherein the non-polyol ester comprises about 5 to 15 wt % of the lubricating oil composition and has a kinematic viscosity at 100° C. of between about 2.5 to 4.5 mm 2 /s. 
     
     
         27 . The lubricating oil composition of  claim 18 ,  19 ,  20 ,  21 ,  22  or  23  characterized by a traction coefficient value measured as the 16N/100° C./30 SSR value of about 0.0191 or less. 
     
     
         28 . The lubricating oil composition of  claim 18 ,  19 ,  20 ,  21 ,  22  or  23  characterized by a Brookfield viscosity at −40° C. of about 21,000 cP or less, a flash point of 230° C. or higher and a NOACK volatility of 15% or less. 
     
     
         29 . The lubricating oil composition of  claim 18 ,  19 ,  20 ,  21 ,  22  or  23  characterized by a CCS viscosity at −25° C. of about 3,600 cP or less. 
     
     
         30 . The lubricating oil composition of  claim 18 ,  19 ,  20 ,  21 ,  22  or  23  characterized by a CCS viscosity at −25° C. of about 3400 cP or less. 
     
     
         31 . The lubricating oil composition of  claim 24  characterized by a traction coefficient value measured as the 16N/100° C./30 SSR value of about 0.0191 or less, a Brookfield viscosity at −40° C. of about 21,000 cP or less and a CCS viscosity at −25° C. of about 3600 cP or less, a flash point of 230° C. or less and a NOACK volatility of 13% or less. 
     
     
         32 . The lubricating oil composition of  claim 31  wherein the ester comprises about 5 to 15 wt % of the lubricating oil and has a kinematic viscosity at 100° C. of between about 2.5 to 4.5 mm 2/s. 
     
     
         33 . The lubricating oil composition of  claim 26  wherein the ester comprises about 8 to 12 wt % of the lubricating oil and has a kinematic viscosity at 100° C. of between about 2.5 to 4.5 mm 2 /s. 
     
     
         34 . The lubricating oil composition of  claim 18 ,  19 ,  20 ,  21 ,  22  or  23  characterized by the absence of viscosity index improvers.