| 摘要 |
TO IMPROVE REDUCTION OF MATERIAL COSTS BY ELIMINATING NECESSITY OF CAREFULLY SELECTED CONTROL OF THE PARTICLE DIAMETER OF A RESIN POWDER COATING MATERIAL AND WIDENING A RANGE OF THE PARTICLE DIAMETER OF THE RESIN POWDER COATING MATERIAL, AND TO FORM A COAT BEING UNIFORM AND PREFERABLE WITHOUT FORMING PINHOLES EFFICIENTLY EVEN WHEN THE LINE SPEED IS INCREASED. IN A METHOD OF FORMING A RUSTPROOF FILM ON A PC STRAND (1) INCLUDING A SERIES OF STEPS ON UNTWISTING A PC STRAND AND LOOSENING SURROUNDING WIRES (1B) FROM A CORE WIRE (1A), APPLYING A SYNTHETIC RESIN POWDER COATING MATERIAL ON OUTER PERIPHERAL SURFACES OF THE CORE WIRE AND SURROUNDING WIRES RESPECTIVELY IN A LOOSENED STATE, HEATING TO ADHERE UNIFORMLY THERETO AND THEN COOLING THE WIRES AND FORMING A RESIN COATING (26) THEREON, AND TWISTING THE SURROUNDING WIRES ON THE CORE WIRE INTO AN ORIGINAL STATE, THE THICKNESS OF THE RESIN FILM IS SET TO 200±80 µM, THE PRE-HEATING IS PERFORMED WITHIN A TEMPERATURE RANGE FROM 60 TO 150°C AND THE POST-HEATING IS PERFORMED WITHIN A RANGE FROM 150 TO 250°C AND THE TEMPERATURE OF THE PRE-HEATING IS SET TO BE LOWER THAN THE TEMPERATURE OF THE POST-HEATING, AND THE SYNTHETIC RESIN POWDER COATING MATERIAL INCLUDING PARTICLES HAVING DIAMETERS IN A RANGE FROM 0.1 TO 250 µM IS USED, AND THE LINE SPEED IN THE SERIES OF STEPS IS SET TO 5 TO 10M/MIN. |
