PECM Issue 27 2017 | Page 23

The high-quality seam is applied in a single step and requires absolutely no finishing work. Photo: EWM AG Welding site in the Hering AG production hall. The pipe is mounted on a rotating bearing and turns automatically. This means that the tube-flange connections can always be welded in PA position. Photo: EWM AG tigSpeed – save up to 50% with the TIG wire feeder from EWM TIG welding had played a fairly insignificant role at Hering. tig S peed : superb seam quality at top speed Robert Bernhard works for Slatina Schweißtechnik, a sales partner for EWM, a welding machine manufacturer based in Mündersbach, Germany. He has been supporting manufacturing at Hering AG for many years and is always on hand to offer advice and assistance to the Head of Production, Manfred Lepp. On one of his visits, Bernhard suggested that Mr Lepp might wish to consider an alternative technique for welding the many tube- flange connections: TIG welding with tigSpeed. EWM tigSpeed is a TIG wire feed welding machine that is perfectly suited to welding tube-flange connections. tigSpeed mimics manual TIG welding by introducing forward and backward movement in addition to a continuous wire feed. As a result, the welding consumable is repeatedly drawn out of the weld pool and passes over drop by drop. In the case of hot wire welding, the welding consumable is preheated. This further increases the deposition rate, which allows the consumable to flow better, thereby producing a very uniform weld seam. The advantages are obvious: thanks to the automatic wire feeding, the welder can concentrate totally on the welding process. Their second hand remains free and can support the guide hand. "It's a great help, particularly with long seams," explains Valmir Xhaferi, a welder at Hering AG. "A flange can be welded onto the tube in a single step – and there are no contact points caused because I don't need to change welding rods." A positioner makes the tube turn continuously. This means that the operating point remains in the same place in the flat position. For the outer seam, this is on top of the tube, and for the inner seam, it is on the upwards-facing side of the inside of the tube. Combined with the high deposition rates of the hot wire technique, this constant working position means that high welding speeds can be achieved while at the same time ensuring outstanding seam quality. E asy handling – quiet working It only took the welders at Hering AG half an hour to get fully up to speed with tigSpeed. Controlled using one- knob operation, handling is really straightforward, and a digital display guarantees reproducible parameter settings. www.ewm-group.com