Working closely with users from the automobile industry, welding technology specialist Fronius International has further evolved the pincer guns used in its acclaimed resistance spot-welding process DeltaSpot. Now available, this second generation of pincer-gun improves both the serviceability and the technology of the system, leading to shorter production downtimes at customers'. A further benefit of these improvements has been to lower operating costs still further, allowing light-alloy sheets to be joined even more economically and with consistently superior quality. Among the outstanding features of these pincer guns are their extremely rugged build and straightforward interface- and maintenance concept. This clears the way for widespread introduction of this innovative resistance spot-welding process in large-scale series production.

The core elements of the second generation of pincer-gun are its reshaped carrier body and the fundamental redesign of the pincer-gun arms and drive motors. Unlike in the previous generation, where the process-tape reeling and unreeling devices, the arm adjustment mechanism and the servo-electric main drive were all integrated within the pincer gun, these components are now located directly on the carrier body. By 'decoupling' the components in this way, the Fronius engineers have made the construction of the pincer-gun arms both simpler and stronger, which is an absolute 'must' in aluminium spot-welding. Even in the standard version, the pincer guns now come with a powerful MFDC transformer that runs at 1000 Hz. Another result of this is that the system readjusts once every millisecond during welding, in order to achieve perfect results. The transformer and the rectifiers have also been moved closer to the electrodes so as to reduce transmission losses.

As part of the overhaul given to the mechanical design, Fronius also restructured the interface between the carrier body and the pincer-gun arms, to make it even more modular. This means that far less design work and equipment are needed when the pincer gun has to be individually adapted to a particular welding task. It also provides greater flexibility regarding the pincer-gun geometry and the 'window' between the arms. The new pincer guns are much quicker to maintain and service, as assemblies such as the transformer, the motor control box, the tape drives and the main drive now feature high-quality plug-in connectors and can be changed in just a few simple steps when needed.

The drives of the new generation of pincer-gun are also equipped with a fail-safe brake. One of the advantages of this for the system operator is that the time-consuming reference cycle is no longer necessary after an automatic pincer-gun changeover, meaning that production can be restarted more quickly.

These innovations give users of the DeltaSpot process a new generation of pincer-guns that has been designed - right down to the last detail - for deployment in large-scale production. In conjunction with the cutting-edge graphical control software 'Fronius Xplorer', DeltaSpot provides an optimally tailored solution for spatter-free resistance spot-welding of light alloys, with consistently high joining quality.

Fronius International GmbH is an Austrian company with headquarters in Pettenbach and other sites in Wels, Thalheim, Steinhaus and Sattledt. With 3,239 employees worldwide, the company is active in the fields of welding technology, photovoltaics and battery charging technology. Around 93% of its products are exported through 19 international Fronius subsidiaries and sales partners/representatives in over 60 countries. With its innovative products and services and 864 active patents, Fronius is the global innovation leader.

Fronius India Private Limited, Pune. Mobile: 098206-05297. Email: sales.india@fronius.com