A gear lubricant composition includes at least 97% by weight, based on the total weight of the lubricant composition, of at least one hydrocarbon-based oil that includes a weight content of isoparaffins ranging from 90 to 0%, a weight content of normal paraffins ranging from 0 to 10% and a carbon content of biological origin greater than or equal to 90% relative to the total weight of the oil, at least 0.01% by weight, based on the total weight of the lubricant composition, of at least one additive selected among the anti-wear additives, extreme pressure additives, anti-corrosion additives, additives having metal-deactivating properties, anti-foam additives, anti-oxidant additives selected among the phenolic anti-oxidants, and the mixtures thereof.

Provided is a mineral base oil that conforms to viscosity grades VG22 to VG100 as defined in ISO 3448 and exhibits a distillation curve with a temperature gradient |DT| of distillation temperature between two points of 2.0 vol % and 5.0 vol % of distillation amount being 6.8 C./vol % or less. A vacuum pump oil containing the mineral base oil is excellent in vacuum characteristics and can conform to viscosity grades VG22 to VG100 as defined in ISO 3448.

The disclosure relates to an electrocrushing drilling fluid with an electrocrushing drilling base fluid including a non-polar oil, water, and glycerin. The base fluid may further include a polar oil and an alkylene carbonate. The electrocrushing drilling fluid may further contain at least one additive. The electrocrushing drilling fluid may have a dielectric constant or dielectric strength of at least a set amount, an electric conductivity less than a set amount, or a combination of these properties. The disclosure further relates to an electrocrushing drilling system containing the electrocrushing drilling fluid and an electrocrushing drill bit.

A transformer oil basestock is disclosed that includes at least 99 wt % of naphthenes and paraffins, based on the total weight of the transformer oil basestock, wherein the weight ratio of naphthenes to paraffins is at least 1, as measured by GC-MS, and wherein the paraffins consist essentially of isoparaffins, as determined by GC-FID. In addition, a transformer oil composition is disclosed that includes the transformer oil basestock, an anti-gassing agent and an antioxidant.

Provided is a method for improving oxidation resistance and deposit resistance of a lubricating oil for use in lubricating a mechanical component. The method includes the step of providing the lubricating oil to the mechanical component and measuring the improved oxidation and deposit resistance. The lubricating oil includes a lubricating oil base stock at from 0 to 80 wt %, at least one branched isoparaffin having a mole % of epsilon carbon as measured by C.sub.13 NMR of less than or equal to 10% at from 20 to 80 wt %, at least one viscosity modifier at from 5 to 20 wt %, and one or more other lubricating oil additives. The oxidation resistance in the CEC L-109 oxidation resistance test is improved to greater than 310 hours to achieve a 100% viscosity increase and the deposit resistance in the TEOST 33C is improve to total deposits of less than 45 mg as compared to oxidation resistance and deposit resistance achieved using a lubricating oil not containing the at least one branched isoparaffin.

Provided is a mineral base oil having a kinematic viscosity at 40 C. of 4.0 mm.sup.2/s or more and less than 6.0 mm.sup.2/s, a kinematic viscosity at 100 C. of 1.0 mm.sup.2/s or more and less than 2.0 mm.sup.2/s, and a flash point of 140 C. or higher. A lubricating oil composition containing the mineral base oil has a high flash point while having a low viscosity and thus having excellent fuel-saving performance when used as a driving system oil and the like.

Methods and systems for manufacturing lubrication oils are disclosed. In one embodiment, a method for manufacturing a lubrication oil includes the steps of receiving into an adsorber unit an unconverted oil (UCO) feedstock comprising five and six ring polynuclear aromatic (PNA) compounds and contacting the UCO feedstock with an adsorbent to remove PNA compounds, thereby forming a treated UCO feedstock with a low concentration of five and six ring PNAs.

Compositions are provided for lubricant base stocks produced from feeds such as vacuum resid or other 510 C.+ feeds. A feed can be deasphalted and then catalytically and/or solvent processed to form lubricant base stocks, including bright stocks that are resistant to haze formation.

The invention is a fluid having a kinematic viscosity from 3 to 6 mm.sup.2/s, a flash point of higher than 120 C. and a pour point lower than 40 C., having a boiling point in the range of from 200 C. to 400 C. and a boiling range below 80 C., said fluid comprising more than 95% isoparaffins and less than 3% of naphthens by weight, a biocarbon content of at least 95% by weight, containing less than 100 ppm aromatics by weight. The invention is also a drilling fluid and the use of the fluid to improve the viscosity of the drilling fluid.

A process for producing naphthenic base oils from low quality naphthenic crude feedstocks. The naphthenic base oils produced by the process have improved low temperature properties at high yields based on feedstock.