junta roscada para tubos de aÇo

• Main Authors: SHIGEO NAGASAKU, TOSHIRO ANRAKU, KEISHI MATSUMOTO, KAZUYUKI NAKASUJI, KUNIO GOTO
• Format: Patent
• Language: Portuguese
• Published: 19.02.2013
• Subjects: BLASTING; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; ENGINEERING ELEMENTS AND UNITS; FIXED CONSTRUCTIONS; FUELS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; JOINTS OR FITTINGS FOR PIPES; LIGHTING; LUBRICANTS; LUBRICATING COMPOSITIONS; MEANS FOR THERMAL INSULATION IN GENERAL; MECHANICAL ENGINEERING; METALLURGY; MINING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS; PEAT; PETROLEUM, GAS OR COKE INDUSTRIES; PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TECHNICAL GASES CONTAINING CARBON MONOXIDE; THERMAL INSULATION IN GENERAL; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATINGINGREDIENTS IN A LUBRICATING COMPOSITION; WEAPONS

A threaded joint for steel pipe formed on a pin and a box having a contact surface including threaded parts and a non-threaded metal contact part and capable of stably assuring a galling resistance and an airtightness without applying compound grease threreto, wherein a solid lubricating film formed with lubricating powder (e.g., molybdenum disulfide) and organic or inorganic binder is formed on the contact surface of at least one of the pin and the box, the ratio of area occupied by the secondary particles of 15 to 60 µm in equi-area equivalent diameter of the lubricating powder in the cross section of the solid lubricating film in thickness direction is 5 to 90%, and fiber-like filler (e.g., inorganic substance whisker) in addition to the lubricating powder is mixed into the solid lubricating film at the mass ratio of the fiber-like filler to the binder of 0.01 to 0.5, whereby, particulary, the galling resistance at high temperatures can be improved.