Turbine oil, and method for using turbine oil

Patent metadata

Field	Value
Publication number	US-11034907-B2
Application number	US-201816491052-A
Country	US
Kind code	B2
Filing date	Mar 8, 2018
Priority date	Mar 8, 2017
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

A turbine oil used in a turbine of a jet engine, containing: a base oil (A) containing a polyol ester (A1); an antioxidant (B) containing an amine-based antioxidant (B1); a polymethacrylate (C) having a weight average molecular weight of 50,000 to 600,000; and an alkyl aromatic compound (D), having a content of the component (D) of 1,000 parts by mass or less per 100 parts by mass of a total resin content of the component (C), and satisfying the following requirements (1) and (2): requirement (1): a viscosity index of 140 or more; and requirement (2): a coking amount attached to a panel of 80 mg or less after a panel coking test under the prescribed condition. The turbine oil has a high viscosity index to such an extent that an oil film can be retained in the use under a high temperature environment as in a turbine of a jet engine mounted on an aircraft, and is excellent in low temperature viscosity characteristics while retaining excellent heat resistance.

First claim

The invention claimed is:

1. A turbine oil for a turbine of a jet engine, comprising:
a base oil (A) comprising a polyol ester (A1);
an antioxidant (B) comprising an amine-based antioxidant (Bp;
a polymethacrylate (C) having a weight average molecular weight of from 150,000 to 500,000;
an alkyl aromatic compound (D),
wherein
a content of the polyol ester (A1) in the base oil (A) is from 80 to 100% by mass based on a total amount of the base oil (A),
a content of the base oil (A) is from 70 to 90% by mass based on a total amount of the turbine oil,
a content of the amine-based antioxidant (B1) in the antioxidant (B) is from 70 to 100% by mass based on a total amount of the antioxidant (B),
a content of the antioxidant (B) is from 0.1 to 5% by mass based on the total amount of the turbine oil,
a content of the polymethacrylate (C) in terms of resin content is from 0.5 to 5.0% by mass based on the total amount of the turbine oil, and
a content of the alkyl aromatic compound (D) is from 110 parts by mass to 800 parts by mass per 100 parts by mass, based on a total resin content of the polymethacrylate (C),
the polyol ester (A1) is an ester of a hindered polyol represented by the following formula (a-1′) with an aliphatic monocarboxylic acid;

wherein R A each independently represent a monovalent hydrocarbon group having 1 to 6 carbon atoms or a methylol group (—CH 2 OH),

the amine-based antioxidant (B1) consists of a combination of a naphthylamine (B11) and a diphenylamine (B12),
a content ratio of the naphthylamine (B11) and the diphenylamine (B12), ((B11)/(B12)), by mass is from 55/45 to 80/20,
the polymethacrylate (C) has a molecular weight distribution, Mw/Mn, of 3.7 or less,
the alkyl aromatic compound (D) consists of an alkylbenzene, an alkylnaphthalene, or a combination thereof, and
wherein the turbine oil satisfies the following conditions (1) and (2):
(1): a viscosity index is 140 or more; and
(2): a coking amount attached to a panel is 80 mg or less after continuously performing a panel coking test for 6 hours according to Fed. Test Method Std. 791-3462 under a condition of a panel temperature of 320° C. and an oil temperature of 130° C., and in a cycle of a splash time of 15 seconds and a suspend time of 30 seconds,

wherein a Brookfield viscosity (BF) of the turbine oil at −40° C. is from 9,000 to 25,000 mPa·s.

2. The turbine oil according to claim 1 , wherein a content of the alkyl aromatic compound (D) is from 0.1 to 17% by mass based on the total amount of the turbine oil.

3. The turbine oil according to claim 1 , wherein a content of metal atoms is less than 100 ppm by mass based on the total amount of the turbine oil.

4. The turbine oil according to claim 1 , wherein a content of an ashless dispersant is less than 0.1% by mass based on the total amount of the turbine oil.

5. A method comprising lubricating a turbine of a jet engine with a turbine oil,
the turbine oil comprising:
a base oil (A) comprising a polyol ester (A1);
an antioxidant (B) comprising an amine-based antioxidant (B1);
a polymethacrylate (C) having a weight average molecular weight of from 150,000 to 500,000; and
an alkyl aromatic compound (D),

wherein
a content of the polyol ester (A1) in the base oil (A) is from 80 to 100% by mass based on a total amount of the base oil (A),
a content of the base oil (A) is from 70 to 90% by mass based on a total amount of the turbine oil,
a content of the amine-based antioxidant (B1) in the antioxidant (B) is from 70 to 100% by mass based on a total amount of the antioxidant (B),
a content of the antioxidant (B) is from 0.1 to 5% by mass based on the total amount of the turbine oil,
a content of the polymethacrylate (C) in terms of resin content is from 0.5 to 5.0% by mass based on the total amount of the turbine oil, and
a content of the alkyl aromatic compound (D) is 2=54 from 110 parts by mass to 800 parts by mass per 100 parts by mass, based on a total resin content of the polymethacrylate (C),
the polyol ester (A1) is an ester of a hindered polyol represented by the following formula (a-1′) with an aliphatic monocarboxylic acid:

wherein R A each independently represent a monovalent hydrocarbon group having 1 to 6 carbon atoms or a methylol group (—CH 2 OH),

the amine-based antioxidant (B1) consists of a combination of a naphthylamine (B11) and a diphenylamine (B12),
a content ratio of the naphthylamine (B11) and the diphenylamine (B12), ((B11)/(B12)), by mass is from 55/45 to 80/20,
the polymethacrylate (C) has a molecular weight distribution, Mw/Mn, of 3.7 or less,
the alkyl aromatic compound (D) consists of an alkylbenzene, an alkylnaphthalene, or a combination thereof, and
wherein the turbine oil satisfies the following conditions (1) and (2):
(1): a viscosity index is 140 or more; and
(2): a coking amount is 80 mg or less after continuously performing a panel coking test for 6 hours according to Fed. Test Method Std. 791-3462 under a condition of a panel temperature of 320° C. and an oil temperature of 130° C., and in a cycle of a splash time of 15 seconds and a suspend time of 30 seconds,

wherein a Brookfield viscosity (BF) of the turbine oil at −40° C. is from 9,000 to 25,000 mPa·s.

6. The turbine oil according to claim 1 , wherein a content of the alkyl aromatic compound (D) is from 1.5 to 15% by mass based on the total amount of the turbine oil.

7. The turbine oil according to claim 1 , wherein the content of the polymethacrylate (C) in terms of resin content is from 0.8 to 3.5% by mass based on the total amount of the turbine oil.

8. The turbine oil according to claim 1 , wherein the BF viscosity of the turbine oil at −40° C. is from 9,000 to 23,000 mPa·s.

9. The method according to claim 5 , wherein a content of the alkyl aromatic compound (D) is from 1.5 to 15% by mass based on the total amount of the turbine oil.

10. The method according to claim 5 , wherein the BF viscosity of the turbine oil at −40° C. is from 9,000 to 23,000 mPa·s.

Assignees

• Idemitsu Kosan Co

Inventors

• Aoki Shinji

Classifications

• C10N2030/08

  Resistance to extreme temperature · CPC title

• C10N2040/13

  Aircraft turbines · CPC title

• C10M105/38 Primary

  of polyhydroxy compounds · CPC title

• C10N2030/02

  Pour-point; Viscosity index · CPC title

• C10M145/14

  Acrylate; Methacrylate · CPC title