Intake manifold

An intake manifold comprising:

• an upper half body;
• and
• a lower half body welded to the upper half body,
• the welded intake manifold including:
• a surge tank having an opening;
• and
• a plurality of inlet pipes extending from the surge tank, each inlet pipe having a proximal end and a distal end, each inlet pipe having an inlet provided at a side wall of the surge tank, and the inlet of each inlet pipe being located side by side with the inlet of another inlet pipe in a direction along which air supplied into the surge tank through the opening flows within the surge tank,
• wherein, proximal portions of an adjacent pair of the inlet pipes are integrated via a plate-like connecting portion provided therebetween, and the plate-like connecting portion is integrated with the side wall of the surge tank by a reinforcing rib that extends perpendicular from the plate-like connecting portion between the proximal portions of the adjacent pair of inlet pipes to a lower portion of the side wall of the surge tank, and
• wherein the half bodies are welded to each other via welding margins provided in the half bodies, and the welding margins extending from the proximal end to the distal end of each inlet pipe and widened toward the proximal portions of the adjacent pair of inlet pipes.