ASME EN positions

The main welding process used to weld pipelines is the MMA method, manual welding with coated electrodes. There are many reasons for this choice. The first is the most obvious the manual electrode is the first product invented that is suitable for arc welding. 

However, still today, when more sophisticated materials and more productive and less expensive techniques are at the users disposal, MMA welding remains a favoured process to weld pipes. Its easy use, capacity to reach positions of difficult accessibility, the simplicity of the necessary generators (or the fact of being able to use motor generators network power is not always available on installation sites), the fact that protective gases (difficult to find in certain countries, in particular third world countries), necessary in welding with solid or cored wires, are not required, all these and others are the reasons for this choice. 

Some classes of cellulosic and basic electrodes have been specially designed to meet the requirements of the grade of steel used to manufacture the pipeline and the safety specifications laid down by standards, but also to equip the user i.e. welders with versatile products created for this specific purpose. 

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