MANUFACTURE OF DRILL SCREW

• Main Authors: KOGASHIWA NORIO, SUEHIRO ATSUO
• Format: Patent
• Language: English
• Published: 26.09.2000
• Edition: 7
• 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; DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS ORMACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS,CLIPS, WEDGES, JOINTS OR JOINTING; DIFFUSION TREATMENT OF METALLIC MATERIAL; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LIGHTING; MECHANICAL ENGINEERING; METALLURGY; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; THERMAL INSULATION IN GENERAL; WEAPONS

PROBLEM TO BE SOLVED: To provide a drill screw with high yield, wherein drill performance and a screwing-in ability are high, and there is no variance in these characteristics. SOLUTION: While a drill screw is stored in a bucket 1, the drill screw is subjected to hot dipping of fused zinc or a fused zinc alloy, by rotating an inner bucket 2F to be processed centrifugally while being heated at a temperature (350 to 500 deg.C) equal to or higher than the melting point of the zinc or zinc alloy by a heating device 5 in atmosphere containing oxygen or inactive gas, and thereby a drill screw having the plated layer of a thickness of 10 to 50 μm is provided. For the zinc alloy, an alloy containing nickel, tin or aluminum, especially a zinc-tin alloy, is used.