Oil cooler having water pipe reinforcement

An oil cooler comprising:

• a core portion formed by alternately stacking a plurality of plates (35, 37) and alternately forming cooling water passages (39) and oil passages (41) between the plates, said core portion having an oil return passage extending longitudinally therethrough;
• an oil tank (57) formed on an upper portion of the core portion (33), the oil tank (57) being formed between an upper plate (47) and a cover plate (55), the upper plate (47) having cooling water passage holes (43) and an oil passage hole (45), the cover plate (55) having water pipe insertion holes (51, 53) on a top surface of the cover plate (55) so as to correspond to the cooling water passage holes (43), the cooling water passage holes (43) and the oil passage hole (45) communicating with the cooling water passages (39) and the oil passages (41) such that oil flows sequentially through said oil passages (41), said oil passage hole (45), said oil tank (57) and said oil return passage;
• and
• two water pipes, (59, 61) passing through the respective pipe insertion holes (51, 53) of the cover plate (55) and through the oil tank (57) to maximize heat transfer from said oil to said water, said water pipes being unperforated between said cover plate (55) and said upper plate (47), said water pipes (59, 61) thus being inserted into the respective cooling water passage holes (43) of the upper plate (47),
• wherein said upper plate and said cover plate both support said water pipes, each of said water pipes being supported in at least two points.