Novel formulation approach to extend the high temperature performance of lithium complex greases in rolling bearings

Patent metadata

Field	Value
Publication number	US-2019062669-A1
Application number	US-201816010704-A
Country	US
Kind code	A1
Filing date	Jun 18, 2018
Priority date	Jul 13, 2017
Publication date	Feb 28, 2019
Grant date	—

Abstract

The present disclosure provides a lithium complex grease with high-temperature resistivity and a method of making the same. The lithium complex grease includes: a lithium complex thickener, a friction modifier, a polymer or copolymer, and at least one synthetic base oil with alkylated naphthalene. The lithium complex grease can be substantially free of polytetrafluoroethylene. Furthermore, the lithium complex grease can have a median failure rate with via ball bearing test (e.g., using the FE9 grease life test method of DIN 51 821) performed at 160° C. of no less than 100 hours.

First claim

1 . A lithium complex grease with high-temperature resistivity, the lithium complex grease comprising:
a lithium complex thickener; a friction modifier; a polymer or copolymer; and at least one synthetic base oil having alkylated naphthalene.

2 . The lithium complex grease of claim 1 , wherein the friction modifier is at least one of a molybdenum (Mo) friction modifier, molybdenum dithiocarbamate (MoDTC), molybdenum dithiophosphate (MoDTP), MOLYVAN® 822, MOLYVAN® 855, MOLYVAN® L, MOLYVAN® 807, MOLYVAN® A, MOLYVAN® 2000, ADEKA SAKURA LUBE 525, MOLYVAN® 3000, or a combination thereof.

3 . The lithium complex grease of claim 1 , wherein the polymer or copolymer comprises at least one of ethylene, propylene, an ethylene-propylene co-polymer, or a combination thereof.

4 . The lithium complex grease of claim 3 , wherein the polymer or copolymer is Vistamaxx™ 6202.

5 . The lithium complex grease of claim 1 , wherein the at least one synthetic base oil includes at least one of an alkylated naphthalene base oil, a polyalphaolefin (PAO) base oil, alkylated naphthalene in PAO base oil, or a combination thereof.

6 . The lithium complex grease of claim 5 , wherein the alkylated naphthalene base oil is at least one of Synesstic™ 5, Synesstic™ 12, or a combination thereof.

7 . The lithium complex grease of claim 5 , wherein the PAO base oil is at least one of SpectraSyn™ 2, SpectraSyn™ 2B, SpectraSyn™ 2C, SpectraSyn™ 4, SpectraSyn™ 5, SpectraSyn™ 6, SpectraSyn™ 8, SpectraSyn™ 10, SpectraSyn™ 40, SpectraSyn™ 100, Syncon® Barrier Oil, or a combination thereof.

8 . The lithium complex grease of claim 1 , wherein the lithium complex grease has at least one of the following:
3% to 30% of the lithium complex thickener; 0.75% to 10% of the friction modifier; 0.25% to 7% of the polymer or copolymer; 10.0% to 40% of the alkylated naphthalene base oil; 13.0% to 76% of the PAO base oil; or a combination thereof.

9 . The lithium complex grease of claim 8 , wherein the lithium complex grease has at least one of the following:
6% to 20% of the lithium complex thickener; 1.0% to 6% of the friction modifier; 0.5% to 4% of the polymer or copolymer; 10.0% to 40% of the alkylated naphthalene base oil; 30.0% to 82.5% of the PAO base oil; or a combination thereof.

10 . The lithium complex grease of claim 1 , wherein the lithium complex grease is substantially free of polytetrafluoroethylene (PTFE), polyester (POE) base oil, or substantially free of PTFE and POE base oil.

11 . The lithium complex grease of claim 1 , further comprising at least one additive selected from the group consisting of an emulsifier, a co-thickener, a corrosion inhibitor, an antioxidant, a wear inhibitor, a tackiness agent, a colorant, an odor control agent, a filler, or a combination thereof.

12 . A method of preparing a lithium complex grease with high-temperature resistivity, the method comprising mixing a lithium complex thickener, a friction modifier, a polymer or copolymer, and at least one synthetic base oil with alkylated naphthalene.

13 . The method of claim 12 , wherein the lithium complex grease has at least one of the following:
3% to 30% of the lithium complex thickener; 0.75% to 10% of the friction modifier; 0.25% to 7% of the polymer or copolymer; 10.0% to 40% of the alkylated naphthalene base oil; at least 13.0% to 76% of the PAO base oil; or a combination thereof.

14 . The method of claim 12 , wherein the lithium complex grease has at least one of the following:
6% to 20% of the lithium complex thickener; 1.0% to 6% of the friction modifier; 0.5% to 4% of the polymer or copolymer; 10.0% to 40% of the alkylated naphthalene base oil; 30.0% to 82.5% of the PAO base oil; or a combination thereof.

15 . The method of claim 12 , wherein the lithium complex grease has a median failure rate with a ball bearing test performed at 160° C. of no less than 100 hours.

16 . The method of claim 12 , wherein the lithium complex grease is substantially free of polytetrafluoroethylene (PTFE), polyester (POE) base oil, or substantially free of PTFE and POE base oil.

17 . The method of claim 12 , wherein the lithium complex grease further comprises at least one additive selected from the group consisting of an emulsifier, a co-thickener, a corrosion inhibitor, an antioxidant, a wear inhibitor, a tackiness agent, a colorant, an odor control agent, a filler, or a combination thereof.

Assignees

• Exxonmobil Res & Eng Co

Inventors

• BRABEZ Nabila
• Graham John K
• Spagnoli James E
• Ennis Raymond C
• Zacharkow John

Classifications

• C10N2040/02

  Bearings · CPC title

• C10N2010/12

  Groups 6 or 16 · CPC title

• C10N2030/06

  Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure · CPC title

• C10M2207/1285

  used as thickening agents · CPC title

• C10M169/00 Primary

  Lubricating compositions characterised by containing as components a mixture of at least two types of ingredient selected from base-materials, thickeners or additives, covered by the preceding groups, each of these compounds being essential · CPC title