| 摘要 |
PURPOSE:To prevent the occurrence of lateral strain in the lower part of a coil of a grain-oriented silicon steel sheet when the coil is finish-annealed by interposing silica sand, etc., between the coil and a coil holder in the form of a layer of a specified thickness and carrying out finish annealing. CONSTITUTION:A coil 1 of a grain-oriented silicon steel sheet is coated with MgO, put on a coil holder 5 in an inner cover 4 with the coiling shaft upright and finish-annealed by heating from the outside of the cover 4. At this time, one or more 7 among silica sand, zircon sand and ceramic powder are interposed between the coil 1 and the coil holder 5 in the form of a layer 8 of 10-50mm thickness and finish annealing is carried out. The occurrence of lateral strain in the coil 1 is remarkably suppressed to increase the yield and commodity value. |
