Method of Producing a Cooling Channel System for Internal Combustion Engines and Piston Produced in This Way

A method for producing a cooling channel piston for an internal combustion engine having a cooling channel in a piston crown, wherein a piston lower part with piston bosses, piston pin bores and piston skirts adjoin the piston crown comprising the steps of:

• producing a piston blank with a radially projecting and peripheral collar in the area of the piston crown;
• reshaping the peripheral collar forming a ring zone wall having a radially distal end and an internal wall inner surface extending from the crown to the distal end;
• in a transition zone between the piston crown and the piston lower part, forming a cooling channel lower wall having a radially extending distal contact area;
• shaping the peripheral collar by extending the ring zone wall distal end below the cooling channel lower wall and distal contact area until the ring zone wall internal wall inner surface forms a radially outer wall of the cooling channel and comes very closely or completely into contact with the cooling chamber lower wall distal contact area positioned in the cooling channel to form a closed cooling channel;
• and
• reshaping the lower end of the ring zone wall to form a defined gap (X) to an upper edge of the piston skirt.