Method of lubricating a tractor hydraulic

Patent metadata

Field	Value
Publication number	US-9057039-B2
Application number	US-200913054623-A
Country	US
Kind code	B2
Filing date	Jul 22, 2009
Priority date	Jul 23, 2008
Publication date	Jun 16, 2015
Grant date	Jun 16, 2015

Abstract

The present invention relates to a method of lubricating a tractor with a lubricating composition containing: an oil of lubricating viscosity and a sulphur-free phosphorus-containing salt of either (i) a hydroxy-substituted di-ester of phosphoric acid, or (ii) a phosphorylated hydroxy-substituted di- or tri-ester of phosphoric acid.

First claim

What is claimed is:

1. A method of lubricating at least one of a wet-brake, a transmission, a hydraulic, a final drive, a power take-off system, and combinations thereof, of a tractor comprising supplying to the tractor a lubricating composition comprising: an oil of lubricating viscosity and a water emulsifying agent comprising a sulphur-free phosphorus-containing salt of either (i) a hydroxy-substituted di-ester of phosphoric acid, or (ii) a phosphorylated hydroxy-substituted di- or tri-ester of phosphoric acid, or a mixture of (i) and (ii),
wherein sulphur-free phosphorus-containing salt is represented by Formula (1a):

wherein
A and A′ are independently H, or a hydrocarbyl group containing 1 to 30 carbon atoms, wherein at least one of A and A′ is a hydrocarbyl group;
each R and R″ group are independently a hydrocarbyl group;
each R′ is independently R, H, or a hydroxyalkyl group;
Y is independently R′, or a group represented by RO(R′O)P(O)—CH(A′)CH(A)- (such as RO(R′O)P(O)—CH 2 CH(CH 3 )—);
x′ ranges from 1 to 5;
m and n are both positive non-zero integers, with the proviso that the sum of (m+n) is equal to 4;
wherein the water emulsifying agent is added to the lubricant composition in an amount from 0.01 wt % to 0.25 wt % phosphorous.

2. The method of claim 1 , wherein the lubricating composition further comprises:
A. 0.1 to 6 weight percent detergent;
B. 0.1 to 3 weight percent antiwear agent;
C. 0.1 to 3 weight percent friction modifier;
D. 0 to 2 weight percent seal swell agent;
E. 50 to 700 ppm foam inhibitor;
F. 0 to 10 weight percent viscosity modifier; and
G. an oil of lubricating viscosity.

3. The method of claim 1 , wherein the oil of lubricating viscosity contains contaminant amounts of water present at 0.05 wt % to 5 wt % of the lubricating composition.

4. The method of claim 1 further comprising a thiadiazole compound or a derivative thereof.

5. The method of claim 4 , wherein the thiadiazole compound is a mercaptothiadiazole.

6. The method of claim 4 , wherein the thiadiazole compound is selected from the group consisting of 2,5-bis(tert-octyldithio)-1,3,4-thiadiazole, 2,5-bis(tert-nonyldithio)-1,3,4-thiadiazole, and 2,5-bis(tert-decyldithio)-1,3,4-thiadiazole.

7. The method of claim 4 , wherein the thiadiazole compound is dimercaptothiadiazole, a thiadiazole incorporated as part of a multi-functional dispersant, or mixtures thereof.

8. The method of claim 7 , wherein the multi-functional dispersant is produced by preparing a mixture of an oil-soluble dispersant and a dimercaptothiadiazole and heating the mixture above 100° C.

9. The method of claim 7 , wherein the multi-functional dispersant is prepared by heating together:
(i) a first dispersant substrate;
(ii) a thiadiazole compound;
(iii) a borating agent; and
(iv) optionally a terephthalating agent.

10. The method of claim 7 , wherein the multi-functional dispersant is prepared by heating together: (a) a dispersant and (b) 2,5-dimercapto-1,3,4-thiadiazole or a hydrocarbyl-substituted 2,5-dimercapto-1,3,4-thiadiazole which is substantially insoluble in a hydrocarbon oil of lubricating viscosity at 25° C., and further either (c) a borating agent, (d) an inorganic phosphorus compound, or (e) a terephthalating agent, or mixtures of (c), (d), and (e), said heating being sufficient to provide a reaction product which is soluble in said hydrocarbon oil at 25° C.

11. The method of claim 1 further comprising a detergent.

12. The method of claim 11 , wherein the detergent contributes 100 ppm to 1100 ppm of metal to the lubricating composition.

13. The method of claim 11 , wherein the detergent is a sulphonate detergent.

14. The method of claim 1 , further comprising a phosphorus antiwear agent or mixture of phosphorus antiwear agents.

15. The method of claim 1 , further comprising a water tolerance agent.

16. The method of claim 1 , wherein the lubricating composition is free of zinc dialkyldithiophosphate.

17. The method of claim 1 , wherein the oil of lubricating viscosity contains contaminant amounts of water present at 0.1 wt % to 2 wt % of the lubricating composition.

Assignees

• Abraham William D
• Lubrizol Corp

Inventors

• Abraham William D

Classifications

• C10N2060/12

  by phosphorus or a compound containing phosphorus, e.g. PxSy · CPC title

• C10N2030/24

  Emulsion properties · CPC title

• C10N2030/43

  Sulfur free or low sulfur content compositions · CPC title

• C10N2030/40

  Low content or no content compositions · CPC title

• C10N2030/12

  Inhibition of corrosion, e.g. anti-rust agents or anti-corrosives · CPC title