Patent ID: 8313688

Claim:
A method for soldering or for the heat-treatment of workpieces in a protective gas atmosphere, the method comprising: conducting a first gas flow that includes a combustion gas into a first inlet, through an installation, and out of a first outlet, wherein the first gas flow travels in a first flow direction; conducting a second gas flow separate from the first gas flow into an into a second inlet, through the installation, and out of a second outlet, wherein the second gas flow travels in a second flow direction, opposite the first flow direction; heating the first gas flow exothermically reacting the combustion gas; downstream of the heating gas flow in the first flow direction transferring heat to the second gas flow from the first gas flow proximate the first outlet; and upstream of heating the first gas flow in the first flow direction transferring heat to the first gas flow from the second gas flow proximate the first inlet, wherein the first gas flow and the second gas flow are conducted into the installation in opposite flow directions and are placed in a counterflow heat-exchanging relation such that, the first gas flow pre-heats the second gas flow adjacent the first outlet and the second inlet and the second gas flow pre-heats the first gas flow adjacent the first inlet and the second outlet.