“Most customers are astonished when they first see the weld seams that we've produced using the MAG process,” explains Roland Hanser, son of the company's founder and MD of the plant division of Hanser Gastechnik. “They find it hard to believe that such a clean weld seam was produced manually using a metal shielding gas rather than by a machine.”

The plant builder laid the foundations for this high level of quality in 2014 when it purchased a TPS/i. Hanser now always relies on these modern MIG/MAG power sources when working on steel constructions in which the seams – with the aid of a manipulator if necessary – are to be welded in the gravity position (PA).

Its welders use the TPS/i to produce longitudinal and circumferential welds for single-walled, cylindrical containers that do not have to meet specific pressure requirements. The finished tack-welded workpiece is moved into the optimum welding position using remote-controlled rotator units. Hanser also opts for MAG welding in conjunction with an electrically powered rotary table when welding cooling or heating pipework, e.g. when welding a flange onto a pipe.

Saving time and money

Hanser's MD says one of the main advantages of the MAG process is its higher welding speed compared with the TIG process. Roland Hanser says: “On DN 50 piping, the effect is not particularly pronounced, but it's a completely different matter with a DN 300 steel pipe where a seam has to be built up using two or three layers. A MAG welder can do that in less than 8min, whereas a TIG welder would need up to 2h.”

The experiences gained in recent months have demonstrated to Hanser that the MAG process is more cost effective for pipe constructions that can be welded in the PA position (with a manipulator if necessary) and that are around 80mm or more in diameter. Hanser continues to use TIG or TIG cold wire processes for seams in out-of-position welding and for the welding of pipes less than DN 80 in size, as well as for components that have to meet higher pressure requirements.

Hanser employee Markus Pirchmoser, a trained mechanical engineer and qualified welding engineer, is certain that the TPS/i power source is a cost-effective and efficient way of MAG welding: “The new Pulse Multi Control and Low Spatter Control characteristics, plus the many small yet intelligent 'aids', such as the arc length and penetration stabilizer, permit even welders with comparatively little experience to achieve results that would otherwise require years of practice with a conventional power source.”

Customised characteristic variants for typical applications, such as LSC Root (Low Spatter Control Root), help to quickly locate the correct parameters. As a result, even the welding of a solid flange to a pipe with a wall that is only 2mm thick poses no problems for the TPS/i.

Functions such as the penetration stabiliser then support the user during the welding process. Using the innovative wire speed control feature of the TPS/i, this function compensates for stickout fluctuations in situations where the welding torch cannot hold the ideal line.

Weld seam guaranteed

The quality of the weld seam is guaranteed, more or less regardless of the skill of the welder, and the amount of rework required at Hanser is low. Pirchmoser says: “What is absolutely fantastic is that we always know we're going to get a spatter-free weld seam.”

Hanser's MD is convinced that the modular design and ease of handling of the power sources also contribute to the high levels of cost effectiveness: “Many manufacturers still put screw joints on the outside of the device, but this is not the case with Fronius – everything is modular.”

Contacting errors and leaks are to all intents and purposes excluded and no tools are needed when assembling and dismantling the devices. Other key factors include the prompt supply of spare parts that Fronius guarantees and the transfer of technology that the welding specialist offers to facilitate the introduction to new applications and techniques.

Roland Hanser comments: “Working with Fronius enables us to increase the cost effectiveness and level of know-how of our company even faster. This means that we are geared up and ready to accomplish our present tasks and those that will come along in the future.”