Arc welding redefined
Arc welding redefined
Keywords: Arc welding, Robotics
Revolutionary innovation opens up new prospects
The limits of arc welding have been redefined during the “digital revolution”. Fronius, a specialist in the manufacture of welding systems,is setting a new example with the cold metal transfer (CMT) process. The CMT technology offers a fundamental alternative to all automated or robot- assisted gas metal-arc (GMA) processes for the joining of thin metal sheets and sets new standards (Plates 2 and 3).
Plate 2The CMT system with the TPS 3200/4000/5000 CMT power sources and the Robacta Drive CMT welding torch is setting new standards in welding technology
Plate 3Butt weld between two AlMg3 sheets 0.8 mm “thick”: CMT welded without clamping, holding and backing devices
GMA welding represents one of the most important value-creating manufacturing processes for users in the automotive and components industries, in the aerospace and space industries or in metal construction and crane building. The CMT process offers them a new arc welding technology for automated and robot-assisted applications. Where welding is concerned “cold” is relative, but with the new process the workpieces to be joined, and above all their weld zones, remain considerably “colder” than with conventional GMA welding. Now it is even possible to “butt” weld or braze thin sheets over 0.3 mm “thick”. The innovations of the CMT process are that it selectively breaks off or breaks up the arc. In this case the movement of the wire is built into the welding process and its control system resulting in perfect, spatter-free metal transfer.
Each time the short-circuit occurs with a frequency up to 70 Hz, the digital process control interrupts the current supply on one hand and controls retraction of the wire on the other. This wire retraction movement assists droplet detachment during short- circuiting.
The current and consequently, the heat input into the materials to be joined are reduced significantly as a result of the controlled interruption of short-circuiting.
For further information visit our Web site: www.fronius.com
