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Troubleshooting Welding Arc Issues: Causes & Solutions

Learn how to identify and resolve common welding arc problems such as spatter, cold joints, cracks, and more. Understand the causes, precautions, and remedies to improve welding quality and efficiency.

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Troubleshooting Welding Arc Issues: Causes & Solutions

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  1. Anglicky v odborných předmětech"Support ofteachingtechnicalsubjects in English“ Tutorial: Engineeringtechnology Topic: Problems with welding arc – causes and defects´ remove Preparedby: Ing. Josef Martinák st. Projekt Anglicky v odborných předmětech, CZ.1.07/1.3.09/04.0002 je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.

  2. Big spatter • Precautions: • To decrease welded flow • To reduce arc length • To control right polarity • According to electrode type • To clean, and dry welded place • Causes: • Too big welding flow • Too long arc • Humidity or dirt on welded edges

  3. Difficult arc ignition • Precautions: • To increase welded flow • No-load voltage of welding source is low for used electrode types • To clean grounding brace surface • To dust off or grind off electrode tip gently and to ignite arc by contact • Causes: • Too low welding flow • Ignition voltage is low • Ignition electrode tip covers ground electrodes

  4. Cold joints • Causes: • Low welding flow • Wrong electrode leading • Too high welding speed • Small electrode diameter

  5. Fissures in crater • Precautions: • To fill crater at welding finish • Causes: • Too quick welding shut down (starting fissure in crater cavity is caused by shrinkage at welded metal solidification)

  6. Root defects • Causes: • Moving welding speed is high • Used electrode diameter is too thick • Space between welded materials is too small • Wrong electrode leading • Precautions: • To decrease welding speed • To choose smaller electrode diameter for root weld • To use right gap between welded parts (e.g. By grinding) • Correct welding technique

  7. Cracks in welded joints • Precautions: • To choose welded material • To decrease cooling speed by correct preheating • To use dried alkaline electrodes • Causes: • Basic material with higher carbon, manganese or other alloyed elements content • Quick cooling in thermally influenced area of basic material • Damp electrodes • ( hydrogenembrittlement)

  8. Crystallizing cracks • Causes: • Wrong electrode type • Basic material with high carbon and sulphur content • Wrong weld geometry • Weld – mainly root layers and tack welds – if not sized sufficiently taking into consideration possible shrinking effect • Precautions: • To use electrodes with alkaline coat whose welded metal is more resistant to crack’s development • To use correct electrode material with goodweldability • To prevent wide spaces among components and to ensure right root penetration

  9. Pores • Precautions: • To re-dry of electrodes according to manufacturer’s instructions or use new ones • To remove paint impurities and corrosive products of welded surfaces, to remove iron scales and to dry humidity on welded surfaces • Causes: • Humidity of wrongly stored electrodes • Impurities or protective paint on welded edges

  10. Arc blowing • Causes: • Electric arc blowing due to magnetic fields • Appearance mostly at direct flow welding • It is shown on weldment edges and in limited space • Precautions: • To fix ground clamp at the place of weld commencement (welding to proceed from grounding clamp) • To use alternative current where possible • To change electrode angle. If possible, to keep the shortest arc length.

  11. Slag inclusions • Causes: • Slag overtake the welding arc • Imperfect slag removal between individual runs • Convex run’s shape makes ´slags´ pockets’ • Wrong welding run’s sequence • Removal: • To increase welding speed or to extend electrode position angle • Accurate slag removal by grinding, if it is necessary • Use right technique of welding runs placing • To choose right welding process

  12. Questions and revision • Describe causes of big spatter.

  13. Literature • DILLINGER, Josef. A KOL. Moderní strojírenství pro školu i praxi. 1. Praha: Europa-Sobotáles, 2007. ISBN 978-80-86706-19-1. • M. HLUCHÝ, J. KOLOUCH, R. PAŇÁK. Strojírenská technologie II Translation: • www.seznam.cz • www.slovnik.cz • JANATA, Petr. Handy slovník technický anglicko-český a česko-anglický. Plzeň: Nakladatelství Fraus, 2000. ISBN 80-7238-075-3 • Lingea LEXIKON 5, Technický slovník anglicko-český a česko-anglický. 2010.

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