| 摘要 |
PURPOSE:To obtain a rim having low production cost and without any public pollution, etc. by forming to the necessary rim shape after an annular body of double structure being widened in its diameter with high pressure from the side of inner diameter and the unification of an iron series plate of the outside and metallic plate of corrosion resistance of the inside. CONSTITUTION:An annular body 12 of a metallic plate (stainless steel or aluminium, etc. for instance) having a little smaller diameter than an annular body 11 of an iron series plate and a thinner thickness and a rich corrosion resistance is inserted into the inner diameter side of the annular body 11 thereof. A double annular body 10 unifying the annular body 11 of iron series plate and an annular body 12 of metallic plate having rich corrosion resistance is obtd. by widening the diameter of the annular body 12 with high pressure from the inner diameter side. The double annular body 10 thereof is formed to the necessary shape. |
