METHOD OF PREPARING GREASE FOR SEALING SCREW CONNECTIONS Russian patent published in 2004 - IPC

FIELD: lubricants. SUBSTANCE: grease base, in particular industrial oil, is preliminarily concentrated in vacuum, preferably at 60-80^(r), and mixed with bactericidal inhibitor, preferably at 40-60^(r), after which are added different fractions of polyfluoroethylene, plastic lubricant (metallurgical grease) and graphite, stirring all components in following proportions, wt %: industrial oil 20-40, inhibitor 0.0005-0.001, polyfluoroethylene PFE-400 2-7, polyfluoroethylene PFE-200 1-5, plastic lubricant 10-20, and graphite - the balance, ratio of PFE-400 to PFE-200 being between 3: 0.7 and 2:1. Grease can be advantageously used in oil and gas production when connecting-disconnecting casing tubes, drilling rods and tubing strings as well as screw connection of pipelines and other equipment. Method id nontoxic. EFFECT: reduced density, improved tribological and tribochemical characteristics and also preserved properties after multiple screwing-unscrewing operations, increased heat resistance within a wide temperature range and corrosion resistance in corrosive hydrogen sulfide-containing media. 4 cl, 1 tbl