DULL ROLL FOR COLD-ROLLING METALLIC SHEET AND ITS MANUFACTURING METHOD

• Main Authors: TACHIBANA KIYOSHI, KIJIMA HIDEO, OGIMOTO SHOZO, YAMASHITA MICHIO
• Format: Patent
• Language: English
• Published: 21.07.2005
• Edition: 7
• Subjects: APPARATUS THEREFOR; CHEMISTRY; ELECTROFORMING; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METALLURGY; PERFORMING OPERATIONS; PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTIONOF COATINGS; PUNCHING METAL; ROLLING OF METAL; TRANSPORTING

PROBLEM TO BE SOLVED: To provide a dull roll for cold-rolling a metallic sheet with which the desired surface property of the roll is obtained in a short time and simply, besides, the variation in the surface roughness of the roll caused by the rolling distance is small and the basic unit of the roll is improved. SOLUTION: This dull roll for cold rolling has chromium plated layer composed of an upper layer and a lower layer on the surface of a base roll the Vickers hardness of which is ≥ 600, the Vickers hardness HV 0.025 of the upper layer and the lower layer of the chromium plated layer are respectively ≥ 850 and 650-950 and the surface of the chromium plated layer is ≥ 0.3μm in arithmetic mean roughness Ra and ≥ 200 in the number PPI of peaks per the length of 1 in.. By this manufacturing method of the dull roll for cold rolling, a first plated layer which is ≥ 0.35 in the arithmetic mean roughness Ra and ≥ 230 in the number PPI of peaks per the length of 1 in. is formed on the surface of the base roll which is ≥ 0.05-2.0 μm in the arithmetic mean roughness Ra and a second plated layer which is ≥ 0.3 μm in the arithmetic mean roughness Ra and ≥ 200 in the number PPI of peaks per the length of 1 in. is further formed. COPYRIGHT: (C)2005,JPO&NCIPI