Method for lubricating internal combustion engine
A method for lubricating an internal combustion engine, the method including: supplying a lubricating oil composition to a cylinder of an internal combustion engine, wherein the internal combustion engine has a mean effective pressure of no less than 1.3 MPa, wherein an integrated intensity ratio of peaks of CaO in a X-ray diffraction spectrum of an ash is no more than 16.5%, the ash being obtained by incinerating the lubricating oil composition in an air at 950° C.
1. A cylinder lubricating oil composition for a premix combustion crosshead diesel engine, the lubricating oil composition comprising:
a mineral base oil or a synthetic base oil or a mixture thereof, as a lubricant base oil; and
(A) a metallic detergent, the component (A) comprising:
(A1) a calcium borate-overbased metallic detergent in an amount of 0.35 to 1.70 mass % in terms of calcium on the basis of the total mass of the composition, the component (A1) comprising a calcium borate-overbased calcium salicylate detergent, or a calcium borate-overbased calcium sulfonate detergent, or any combination thereof; and
(A2) a calcium carbonate-overbased metallic detergent in an amount of 0.35 to 1.30 mass % in terms of calcium on the basis of the total mass of the composition, the component (A2) comprising a calcium carbonate-overbased calcium salicylate detergent, or a calcium carbonate-overbased calcium sulfonate detergent, or any combination thereof,
wherein an integrated intensity ratio of peaks of CaO in a X-ray diffraction spectrum of an ash is no more than 16.5%, the ash being obtained by incinerating the lubricating oil composition in an air at 950° C.;
a molar ratio B/Ca of a boron content B (unit: mol) of the lubricating oil composition derived from the component (A) and a calcium content Ca (unit: mol) of the lubricating oil composition derived from the component (A) is no less than 0.52; and
the lubricating oil composition is used to lubricate at least a cylinder in a premix combustion crosshead diesel engine, wherein the premix combustion crosshead diesel engine uses a main fuel having a flash point of no more than 15° C.
2. The lubricating oil composition according to claim 1 , further comprising:
one or more selected from the group consisting of: (B) an ashless dispersant, (C) a phosphorus-containing anti-wear agent, (D) an amine antioxidant, and (E) an oil-soluble organic molybdenum compound.
3. The lubricating oil composition according to claim 1 ,
wherein the component (A1) consists of
the calcium borate-overbased calcium salicylate detergent, or
the calcium borate-overbased calcium sulfonate detergent, or
any combination thereof; and
the molar ratio B/Ca is 0.52 to 1.43.
4. The lubricating oil composition according to claim 1 ,
wherein the lubricating oil composition has a kinematic viscosity at 100° C. of 16.3 to 21.9 mm 2 /s.
5. A method for lubricating a cylinder of a premix combustion crosshead diesel engine, comprising:
a) supplying the lubricating oil composition as defined in claim 1 to a cylinder of a premix combustion crosshead diesel engine, wherein the premix combustion crosshead diesel engine has a mean effective pressure of no less than 1.3 MPa; and
b) making a main fuel ignite in the cylinder, wherein the main fuel has a flash point of no more than 15° C.
6. The method according to claim 5 ,
wherein the main fuel consists of
a C 1-4 hydrocarbon, or
dimethyl ether, or
any combination thereof.
7. The method according to claim 6 ,
wherein the b) making a main fuel ignite in the cylinder comprises:
i) compressing a fuel-air mixture of the main fuel and an air in the cylinder; and
ii) injecting a pilot fuel into the cylinder, to ignite the fuel-air mixture,
wherein the pilot fuel consists of a heavy fuel oil, a light fuel oil, or kerosene, or any combination thereof.
8. A lubricating oil composition for a premix combustion middle-speed trunk piston diesel engine, the lubricating oil composition comprising:
a mineral base oil or a synthetic base oil or a mixture thereof, as a lubricant base oil; and
(A) a metallic detergent, the component (A) comprising:
(A1) a calcium borate-overbased metallic detergent in an amount of 0.25 to 1.20 mass % in terms of calcium on the basis of the total mass of the composition, the component (A1) comprising a calcium borate-overbased calcium salicylate detergent, or a calcium borate-overbased calcium sulfonate detergent, or any combination thereof; and
(A2) a calcium carbonate-overbased metallic detergent in an amount of 0.25 to 0.90 mass % in terms of calcium on the basis of the total mass of the composition, the component (A2) comprising a calcium carbonate-overbased calcium salicylate detergent, or a calcium carbonate-overbased calcium sulfonate detergent, or any combination thereof,
wherein an integrated intensity ratio of peaks of CaO in a X-ray diffraction spectrum of an ash is no more than 16.5%, the ash being obtained by incinerating the lubricating oil composition in an air at 950° C.;
a molar ratio B/Ca of a boron content B (unit: mol) of the lubricating oil composition derived from the component (A) and a calcium content Ca (unit: mol) of the lubricating oil composition derived from the component (A) is no less than 0.52; and
the lubricating oil composition is used to lubricate at least a cylinder in a premix combustion middle-speed trunk piston diesel engine, wherein the premix combustion middle-speed trunk piston diesel engine uses a main fuel having a flash point of no more than 15° C.
9. The lubricating oil composition according to claim 8 , further comprising:
one or more selected from the group consisting of: (B) an ashless dispersant, (C) a phosphorus-containing anti-wear agent, (D) an amine antioxidant, and (E) an oil-soluble organic molybdenum compound.
10. The lubricating oil composition according to claim 8 ,
wherein the component (A1) consists of
the calcium borate-overbased calcium salicylate detergent, or
the calcium borate-overbased calcium sulfonate detergent, or
any combination thereof; and
the molar ratio B/Ca is 0.52 to 1.43.
11. The lubricating oil composition according to claim 8 ,
wherein the lubricating oil composition has a kinematic viscosity at 100° C. of no less than 9.3 mm 2 /s and less than 16.3 mm 2 /s.
12. A method for lubricating a premix combustion middle-speed trunk piston diesel engine, the method comprising:
a) supplying the lubricating oil composition as defined in claim 8 to a cylinder of a premix combustion middle-speed trunk piston diesel engine, wherein the premix combustion middle-speed trunk piston diesel engine has a mean effective pressure of no less than 1.3 MPa; and
b) making a main fuel ignite in the cylinder, wherein the main fuel has a flash point of no more than 15° C.
13. The method according to claim 12 ,
wherein the main fuel consists of
a C 1-4 hydrocarbon, or
dimethyl ether, or
any combination thereof.
14. The method according to claim 13 ,
wherein the b) making a main fuel ignite in the cylinder comprises:
i) compressing a fuel-air mixture of the main fuel and an air in the cylinder; and
ii) injecting a pilot fuel into the cylinder, to ignite the fuel-air mixture,
wherein the pilot fuel consists of a heavy fuel oil, a light fuel oil, or kerosene, or any combination thereof.
15. A lubricating oil composition for a turbocharged gasoline engine, the lubricating oil composition comprising:
a mineral base oil or a synthetic base oil or a mixture thereof, as a lubricant base oil; and
(A) a metallic detergent, the component (A) comprising:
(A1) a calcium borate-overbased metallic detergent in an amount of 0.10 to 0.28 mass % in terms of calcium on the basis of the total mass of the composition, the component (A1) comprising a calcium borate-overbased calcium salicylate detergent, or a calcium borate-overbased calcium sulfonate detergent, or any combination thereof; and
(A2) a calcium carbonate-overbased metallic detergent in an amount of 0.10 to 0.18 mass % in terms of calcium on the basis of the total mass of the composition, the component (A2) comprising a calcium carbonate-overbased calcium salicylate detergent, or a calcium carbonate-overbased calcium sulfonate detergent, or any combination thereof,
wherein an integrated intensity ratio of peaks of CaO in a X-ray diffraction spectrum of an ash is no more than 16.5%, the ash being obtained by incinerating the lubricating oil composition in an air at 950° C.;
a molar ratio B/Ca of a boron content B (unit: mol) of the lubricating oil composition derived from the component (A) and a calcium content Ca (unit: mol) of the lubricating oil composition derived from the component (A) is no less than 0.52; and
the lubricating oil composition is used to lubricate at least a cylinder in a turbocharged gasoline engine.
16. The lubricating oil composition according to claim 15 , further comprising:
one or more selected from the group consisting of: (B) an ashless dispersant, (C) a phosphorus-containing anti-wear agent, (D) an amine antioxidant, and (E) an oil-soluble organic molybdenum compound.
17. The lubricating oil composition according to claim 15 ,
wherein the component (A1) consists of
the calcium borate-overbased calcium salicylate detergent, or
the calcium borate-overbased calcium sulfonate detergent, or
any combination thereof; and
the molar ratio B/Ca is 0.52 to 1.43.
18. The lubricating oil composition according to claim 15 ,
wherein the lubricating oil composition has a kinematic viscosity at 100° C. of no less than 4.0 mm 2 /s and less than 9.3 mm 2 /s.
19. A method for lubricating a premix combustion turbocharged gasoline engine, the method comprising:
a) supplying the lubricating oil composition as defined in claim 15 to a cylinder of a turbocharged gasoline engine, wherein the turbocharged gasoline engine has a mean effective pressure of no less than 1.3 MPa; and
b) making a fuel ignite in the cylinder, wherein the fuel consists of gasoline.