| 摘要 |
PROBLEM TO BE SOLVED: To improve the yield of a manifold by assuring a sufficient connecting margin by suppressing a thickness reduction of a branch tube and reducing the possible position of a welding defect by suppressing the welding positions to a minimum limit. SOLUTION: A method for manufacturing the manifold 6 having branch tubes 8 comprises a deep drawing step of holding a thin plate 7 by a pressing mold and press forming the branch tubes 8; a tube forming step of roll forming the plate 7 and forming a tube 9 by connecting both side edges 7a, 7b; a bulging step of setting the tube 9 in a bulging mold, and pressurizing the tube 9 from an interior to size the tube in a desired shape; and a cutting step of cutting the distal end of the tubes 8. COPYRIGHT: (C)2004,JPO
|
