Exhaust manifold and method of manufacturing the exhaust manifold

An exhaust manifold comprising:

• a body portion having a plurality of branch pipes in which base end portions of the branch pipes are joined together, and distal end portions of the branch pipes branch from each other;
• and
• a flange portion having a plurality of openings to which the distal end portions of the branch pipes are inserted, respectively, wherein:
• the body portion includes a first split body having a plurality of first semi-cylindrical portion, and a second split body having a plurality of second semi-cylindrical portions;
• the first semi-cylindrical portions of the first split body and the second semi-cylindrical portions of the second split body overlie each other, respectively, and define the branch pipes;
• the exhaust manifold includes a first weld bead and a plurality of second weld beads, the first weld bead welding the first semi-cylindrical portion and the second semi-cylindrical portion to each other from an outer surface side, the first semi-cylindrical portion and the second semi-cylindrical portion defining one of the branch pipes, the second weld beads welding an outer peripheral portion of the one of the branch pipes to an edge portion of the opening;
• at least one of the second weld beads partially overlaps the first weld bead;
• and
• end portions of neighboring second weld beads overlap each other and are separated from the first weld bead.