Contact welding tool and method for operating same

A contact welding tool for plasticizing and forming thermoplastic materials, comprising:

• a heating element comprising a thin-walled region having at least one contact surface arranged to contact a workpiece, the thin-walled region at least partially defining an intermediate space;
• at least one heating source arranged facing the thin-walled region within the intermediate space and configured to heat the at least one contact surface to an operating temperature of at least 150° C.;
• at least one cooling device having a coolant tube wherein the cooling device is configured to supply a cooling medium to the coolant tube;
• wherein the at least one heating source is an infrared radiation source configured to emit infrared radiation in the short-wave infrared range;
• wherein the coolant tube has an opening within the intermediate space serving as an inlet opening for the cooling medium, wherein the cooling device is configured to actively cool the thin-walled region by introducing the cooling medium into the intermediate space via the inlet opening so that the cooling medium flows through the intermediate space and exits the intermediate space via an outlet opening;
• and
• wherein the coolant tube has a diameter of 2 mm to 4 mm and the cooling device is configured to introduce the cooling medium into the intermediate space via the inlet opening at a pressure between 4 bar and 8 bar.