E-Book Overview
Rautaruukki Corporation. Helsinki.MFI 05.101EN/05.2009. 30p. Resistance welding manual was compiled in order to provide assistance to Ruukki’s customers and partners (like research institutes and education departments) who are resistance welding in their production process or planning to invest in resistance welding. The manual includes background and advice in choosing welding parameters and recommended welding parameters for both cold-rolled un-coated sheets and metal coated sheets of Ruukki.
E-Book Content
Resistance Welding Manual Foreword Resistance welding manual was compiled in order to provide assistance to Ruukki’s customers and partners (like research institutes and education departments) who are resistance welding in their production process or planning to invest in resistance welding. The manual includes background and advice in choosing welding parameters and recommended welding parameters for both cold-rolled un-coated sheets and metal coated sheets of Ruukki. Ruukki is a metal expert you can rely on all the way, whenever you need metal-based materials, components, systems and total solutions. We constantly develop our product range and operating models to match your needs. 2 Resistance Welding Manual 1. Table of contents 1. Introduction to resistance welding................................................................................................3 2. Resistance welding in steel sheet lap joints................................................................................4 3. Adjustable resistance welding parameters..................................................................................4 Welding current and weld time........................................................................................................5 Electrodes and electrode force........................................................................................................5 Squeeze and hold time.......................................................................................................................6 Other adjustable parameters...........................................................................................................7 4. Heat input.............................................................................................................................................7 Heat balance.........................................................................................................................................7 5. Electric resistance of workpiece.....................................................................................................8 6. Weldability of cold-rolled uncoated and coated steel sheets..................................................8 Sheet metal weldability.....................................................................................................................8 Resistance welding of galvanised steel sheets.........................................................................10 Welding of glued and paint-coated sheets.................................................................................. 11 The impact of dirt, oxides and protective oils on resistance welding.................................. 11 7. Resistance welding equipment....................................................................................................... 11 8. Electrodes........................................................................................................................................... 12 9. Resistance spot welding.................................................................................................................. 13 Stages of resistance spot welding................................................................................................ 14 Growth of weld nugget...............