Extruded Fin Tube

An Electric Current Is Applied By Contacts On The Square Fins (by Using Special Contours) And Tube And The Resistance In This Circuit Produces The Heat Necessary For Welding. Maximum Resistance And Therefore Maximum Heating Occur At The Interface Between The Fin And The Tube. Pressure To Forge The Square Fins And The Tube Together At The Point Of Maximum Heating Is Applied By Various Forms Of Tooling. These Resistance Welding Processes Produce A Strong Metallurgical Bond Between The Fin And The Tube While Minimizing The Heat Affected Zone (HAZ) In The Tube.