TwinWeld Sweden AB
Plasma Welding
TwinWeld Sweden AB
Plasma Welding: A High-Performance Welding Process
Plasma welding is an advanced process similar to TIG welding, but with some distinct advantages. A key difference is the use of both an internal and an external gas nozzle to create and protect the arc. In the inner nozzle, the plasma gas circulates around a centred tungsten electrode. At the same time, the protective gas flows through the outer nozzle, which provides the same protective function as in TIG welding.
Plasma welding can be categorized into three main classes depending on the current range:
1. Microplasma (0.1-15 A): Perfect for welding very thin materials down to 0.03 mm.
2. Medium Plasma (15-100 A): Suitable for welding thin sheets to minimize deformation and achieve high quality.
3. Keyhole Plasma Welding (>100 A): Named for the "keyhole" formed when the beam penetrates the joint edges in a butt joint. This ensures full penetration and can be applied to sheet thicknesses from 3 to 8 mm.
Advantages of Plasma Welding:
• Very high welding speed, up to 400% faster than conventional TIG welding.
• Ability to weld butt joints without filler material in sheet thicknesses up to 8 mm.
• Keyhole technique ensures full penetration.
• Microplasma enables welding in extremely thin materials.
• Minimal impact on the heat-affected zone of the sheet and minimal deformation.
• Produces a small weld bead and root reinforcement.
Applications of Plasma Welding:
Plasma welding is mainly used in the aerospace, nuclear, and defense industries for exclusive materials such as titanium, zirconium, and beryllium. It is also popular for automated welding of stainless steel pipes. Although the method is used to a limited extent for welding ferritic steels, it has a wide range of applications and offers outstanding performance and precision.
We have procedures for material thicknesses between 2-10 mm according to EN15614-5 for materials such as Titanium, C276, and Stainless Steel 316L.