Abstract: A header plate has a central portion in which at least one row of holes are formed. The heat exchanger includes tubes which are fitted in these holes, and each hole is made in a press-formed element which comprises at least two raised elements aligned with each other. The respective dimensions of these raised elements are predetermined, and they are adapted to be pierced individually or in combination by means of perforating tools having different characteristic dimensions in at least the direction in which the raised elements are aligned with each other. Tubes of different dimensions in at least this alignment direction can be introduced into the holes.
Abstract: A heat exchanger assembly (10) for transferring heat comprising a heat exchanger core (12) having adjacent hollow tubes (14), heat exchanger fins (16) interconnecting adjacent tubes (14), and a plastic header (18, 118) molded about each of the ends of the tubes (14). A cover (22, 122) at the top and bottom of the heat exchanger core (12) attaches to each of the headers (18, 118) about the ends of the tubes (14) to enclose the tank. The invention includes a method for making the heat exchanger assembly (10) by molding the plastic header (18, 118) about each of the ends of the hollow tubes (14).