An Austrian SME is marketing its modified TIG welding process, enabling automated mass applications, worldwide. It is highly efficient for thin sheet metal applications (0.3-3 mm; steel, aluminium, material combinations, etc.). It is spatter-free and saves costs by reduction of filler metal, gas consumption and downtime. As a one-stop shop, the SME offers customised solutions for a wide range of applications (commercial agreement with technical assistance, technical/research cooperation sought)
Tungsten inert gas welding (TIG welding) is a modern process for joining metals. An electric arc is formed between the workpiece and an electrode made of tungsten. The filler material is fed into the arc and melted in this way. Shielding gases such as argon are used to prevent the molten material from reacting (oxidising) with the surrounding air. Particularly high seam qualities can be achieved.
A major disadvantage of TIG welding is that it has to be carried out manually due to the lack of controllability. This is demanding for the welder and is often not suitable for mass applications (automotive, household appliances) due to the low process speeds.
The Austrian SME (with 30 years of experience in the field of special machine construction) has successfully developed a modified TIG welding process that could be automated, thus enabling mass applications.
Compared to conventional TIG processes, the electrode tip is located outside the nozzle, which means that the arc is ignited outside a jet-optimised nozzle. This enables a focused arc with a higher power density and higher effective temperatures on the workpiece while minimising the heat-affected zone and reducing the thermal load on the nozzle. This leads to:
- automated process due to high controllability
- Increased productivity (higher welding speed and greater penetration depth)
- highest weld seam quality thanks to precise heat input and minimal distortion; no post-processing of the weld seam is necessary thanks to the spatter-free process;
- greatly increased nozzle service life due to reduced wear and material ageing
The internal geometry of the nozzle has been designed specifically to optimise the flow conditions and change the arc shape. This also reduces gas consumption (argon) and thus the variable process costs.
In addition, a pneumatic cathode clamping system was developed for the fastest automatic cathode change. In the normal TIG process, the entire torch head or cathod has to be replaced manually due to wear. The process then has to be stopped for a few minutes each time. The automatic changer does this in just a few seconds. In addition, short cathodes grinded on both sides can be used.
The plasma torches are manufactured by the Austrian SME itself and therefore the arc shape (nozzle geometry) can be adjusted to the joining concept (wide, narrow, rotating, etc.). This enables customised applications. The new process can be implemented inline (in existing systems) or via complete systems with different degrees of automation depending on customer requirements.
Different equipment for various applications have already been sold worldwide.
The process is suitable for joining thin sheets of steel, stainless steel, galvanised steel, aluminium (with or without alternating current) and many complex material combinations. Typical market sectors are white goods, small appliances, automotive, (public) transport, e-mobility, electronics industry, etc.
- sheet thicknesses: 0.3 - 3 mm
- welding speeds: up to 3 m/min
- Argon (mixtures): 5-8 l/min (no additional shielding gas required)
- energy density: 10 to the power of 6 W/cm² with cathode diameter of 3.2 mm; 10 A - 300 A welding current
- when using filler materials: significant reduction (5 times less compared to metal active gas welding)
- automatic cathode changer: < 15 sec cathode change; 24 change cycles
The Austrian company is mainly looking for industrial partners in the above mentioned fields to buy the novel technology for their products or processes. It offers technical assistance for installation and operation (commercial agreement with technical assistance), adaptations to specific requirements (technical cooperation) and conjoint development of new applications (technical/research cooperation).