| 摘要 |
<p>Disclosed is branch pipes for an exhaust manifold in which a fitting part (10a,11a,12a,13a) to be fit into a manifold container (30) comprises a group of pipe members, wherein a cross section of the fitting part (10a,11a,12a,13a) of each branch pipe (10,11,12,13) is shaped into a fan-like shape, and the cross sectional area of the branch pipe (10,11,12,13) is substantially equal to that of the branch pipe (10,11,12,13) before the branch pipe is worked. <??>The specification also discloses a method of manufacturing the exhaust manifold branch pipes (10,11,12,13) as last mentioned. In the manufacturing method comprises a step of expanding the end of each pipe member, and another step of shaping the expanded end of the pipe member into a fan-like shape in cross section. <IMAGE></p> |
