JIANGSU HAOHUA INDUSTRY GROUP

 High Frequency Resistance Welded Finned Tubes

Technical Details

FIN Details

Fins Thickness : Min. 0.8 Mm To Max. 3 Mm In Cs Fin & 1 Mm To 2.5 Mm In Ss

Fins Height : Min 0.25” (6.35 Mm) To Max.1.5” (38 Mm), (depending On The Bare Tube Outer Diameter On Which Fining Is To Be Done)

Fin Density : Min 43 Fins Per Meter To Max. 287 Fins Per Meter (depending On The Fin Density –FPM, And Fin Thickness)

Material : Carbon Steel, Stainless Steel, Alloy Steel, Duplex Steel And Incolloy. (Any Ferrous Material)

TUBE Details

Tube Diameter : 26 Mm Od Min To 168.3 Mm Od Max.

Tube Thickness : Minimum 2 Mm

Tube Mateial : Carbon Steel, Stainless Steel, Alloy Steel ,duplex Steel, Super Duplex Steel, Inconel, High Chrome High Nickle & Incolloy (Any Ferrous Material), CK 20 material and some other material.

Production Technique & Applications

HF Resistance Welding Usually Employs Frequency Of 400khz. With This Technique, The Fin Is Wound On Edge Around The Tube And A Continuous Weld Is Obtained. The Forming Of The Fin Around The Tube And The Heat Of Welding Causes Some Upsetting Or Widening Of The Base Of The Fin Which Results In A Contact Area Wider Than The Fin Itself. Heat Is Thus Transferred Across The Whole Interface And Not Just Through The Weld Itself. However, The Interface Area Is Much Smaller And Quality Of The Hf Weld Is More, This Is Important In Maintaining Negligible Resistance To Heat Transfer Between The Fin And Tube. Hf Welded Fins Shows Less Extensive Heat Affected Zone, The Affected Depth Is Minimal When Compared To Other Types Of Welding. The Use Of High Frequency Current Results In Very Localized Heating Of The Tube Surface And The Edge Of The Fin Due To “skin Effect”, This Results In Higher Weld Speeds And Greater Ease In Welding Difficult Material Combinations. The Hf Process Also Allows Much Thicker Fins To Be Welded. In Fact, It Is Now Possible To Weld Fins Heavy Enough To Replace Those Previously Available Only With Mig, Tig And Stud Welding Processes, Which Do Not Give Equivalent Quality Or Cost Effectiveness.

Helical Solid Finned Tube

The Important Features Of This Configuration Are Efficient, Effective Bond Of Fin To Tube Under All Conditions Of Temperature And Pressure, And Ability To Withstand High Fin Side Temperatures. This Solid Fin Configuration Is The Most Rugged And Will Stand Up To Repeated Cleanings For Fin Fouling If That Is A Problem In The Application.

Helical Serrated Finned Tube

The Important Features Of This Configuration Too Is Efficient, Effective Bond Of Fin To Tube Under All Conditions Of Temperature And Pressure, And Ability To Withstand High Fin Side Temperatures. This Serrated Fin Configuration Is Even Better To Withstand The Fin Fouling If That Is A Problem In The Application. This Gives Better Heat Transfer Properties Compared To Solid Fins.