Embodiments disclosed herein generally relate to magnetic recording systems having a spindle motor and, more particularly, to an optimized lubricant for bearings within the spindle motor. A lubricant used in a fluid dynamic bearing motor has an antioxidant additive and a charge control agent dissolved in a diester base oil. The charge control agent is chemically attached to the same diacid reactant used in the diester lubricant base oil, and is prepared through an esterification reaction. The charge control agent is then dissolved in the lubricant base oil. The charge control agent is soluble in the lubricant, and is resistant to free radical oxidation. The charge control agent effectively controls the charge of the lubricant by creating electron donor/acceptor sites in the lubricant, facilitating an independent electronic pathway through the lubricant.

The invention relates to a food-grade high-temperature lubricant, more particularly a high-temperature oil and a high-temperature grease, comprising the following components: a) at least one oil selected from a trimellitic ester or a mixture of different trimellitic esters, alkylaromatics, preferably an aliphatically substituted naphthalene, or estolides; b) a hydrogenated or fully hydrogenated polyisobutylene or a mixture of hydrogenated or fully hydrogenated polyisobutylene; and c) additives individually or in combination.

In the case of the high-temperature grease, a thickener is added.

The invention relates to a food-grade high-temperature lubricant, more particularly a high-temperature oil and a high-temperature grease, comprising the following components: a) at least one oil selected from a trimellitic ester or a mixture of different trimellitic esters, alkylaromatics, preferably an aliphatically substituted naphthalene, or estolides; b) a hydrogenated or fully hydrogenated polyisobutylene or a mixture of hydrogenated or fully hydrogenated polyisobutylene; and c) additives individually or in combination.

In the case of the high-temperature grease, a thickener is added.

A downhole motor or pump assembly that includes a stator and a rotor rotatable within the stator. The stator includes a tubular housing and an overlay deposited by cold spray onto an interior of the housing to form overlay lobes along a first length of the stator. The downhole motor or pump may be used to perform downhole operations.

A downhole motor or pump assembly that includes a stator and a rotor rotatable within the stator. The stator includes a tubular housing and an overlay deposited by cold spray onto an interior of the housing to form overlay lobes along a first length of the stator. The downhole motor or pump may be used to perform downhole operations.

A lubricating oil composition for an internal combustion engine, the composition including: a lubricating base oil comprising at least one mineral base oil or at least one synthetic base oil or any combination thereof, the lubricating base oil having a kinematic viscosity at 100° C. of 4.0 to 4.5 mm.sup.2/s and a NOACK evaporation loss at 250° C. of no more than 15 mass %; (A) a calcium-containing metallic detergent in an amount of no less than 1000 mass ppm and less than 2000 mass ppm in terms of calcium on the basis of the total mass of the composition; (B) a magnesium-containing metallic detergent in an amount of 100 to 1000 mass ppm in terms of magnesium on the basis of the total mass of the composition; and optionally (C) a viscosity index improver in an amount of less than 1 mass % on the basis of the total mass of the composition.

A lubricating oil composition for an internal combustion engine, the composition including: a lubricating base oil comprising at least one mineral base oil or at least one synthetic base oil or any combination thereof, the lubricating base oil having a kinematic viscosity at 100° C. of 4.0 to 4.5 mm.sup.2/s and a NOACK evaporation loss at 250° C. of no more than 15 mass %; (A) a calcium-containing metallic detergent in an amount of no less than 1000 mass ppm and less than 2000 mass ppm in terms of calcium on the basis of the total mass of the composition; (B) a magnesium-containing metallic detergent in an amount of 100 to 1000 mass ppm in terms of magnesium on the basis of the total mass of the composition; and optionally (C) a viscosity index improver in an amount of less than 1 mass % on the basis of the total mass of the composition.

A lubricating oil composition is provided, including a fullerene and a base oil, in which the fullerene is a fullerene sublimate, and the base oil is a multiply alkylated cyclopentane oil or an ionic liquid.

A lubricating oil composition is provided, including a fullerene and a base oil, in which the fullerene is a fullerene sublimate, and the base oil is a multiply alkylated cyclopentane oil or an ionic liquid.

Provided are a method of producing a lubricating base oil composition including a) reacting at least a part of waste plastic pyrolysis oil having a boiling point in a range higher than 340° C. to remove impurities and structurally isomerizing the oil; and b) hydroisomerizing at least a part of the product of step a), and a lubricating base oil composition produced therefrom. A lubricating base oil, which has more methyl branches than petroleum-based lubricating base oil, to have improved low-temperature properties may be provided.