African Fusion August 2018

Auto-darkening helmets: the optrel advantage • Scattered light: Class 1 • Homogeneity: Class 1 • Angular dependence: Class 1

Auto-darkening helmets from optrel, available from Thuthuka Welding in South Africa, offer welders adaptive shade level adjustment that can au- tomatically and continuously vary the shade level – typically in the range of 2.5 to 13 – to give thewelder the optimal view of the weld joint and the arc. This is done by using a brightness sensor and to measure the intensity of the welding arc and then electronically altering the orientation of liquid crystal cells (LCC) in the shade to provide opti- mal protection, regardless of the weld- ing parameters being used. Replacements of the glass shade to suit different current levels or processes and manually having to drop the hel- met before and lift it after welding to see under normal light conditions are no longer required. By using an optrel auto-darkening helmet, it is possible to see the weld joint clearly and safely at all times, whether the welding arc has been struck or not. This is possible thanks to optrel’s patented Autopilot function, a unique 5-sensor infrared (IR) array that mea- sures the brightness of the welding arc and automatically adjusts to the cor- rect shade level. Autopilot can be shut off on demand, however, allowing the shade level to be adjusted manually, if preferred, within a safe range. With the autopilot function activated the welder can adjust the shade level up or down by shades, depending on the strength of the welder’ eyes. A special UV/IR-filter developed by optrel also enables a real colour view and offers the welder ultra-HD in true colour – and the 2.5 shade level is a world first visual quality level. This is in stark contrast to manual helmets with ‘smoked’ glass, which typically tint everything towards green, significantly reducing visual clarity and contrast. The optrel e684 ADF, for example, offers the highest level of image quality

Other functions included in the optrel e684 ADF and other models include: Twilight mode, which reduces the red glow after welding; Grinding mode, which can be activated at a touch of a button; an optional silver helmet colour, to reflect 23%of weld heat; and a sensor slider to increase the sensor field of view from 60° to 80°. Overhead welding is also possible and a hard-hat adaptor can be fitted. Extremely good angular depen- dence further supports the quality of the optrel helmet’s auto-darkening filter (ADF),making themvery comfortable for use by welders – and with the latest op- trel Panoramax helmet, the visual field has been increased six-fold compared to all other auto-darkening helmets. An integrated particle filter of the highest safety class (TH3) can also be incorporated into these optrel helmets to reliably protect welders from smoke, aerosols, and dust. And because these remove welding fume at source, they are more cost-effective than external or

Adaptive Shade Autopilot technology from optrel automatically adjusts the shade level to the welders’ preferred settings to offer full high-definition viewing of the seam, weld pool and arc.

portable fume extraction systems. Welders need to cope with harsh work conditions such as fumes, con- stantly changing levels of brightness and heat. In addition, they have a high level of responsibility. A flawed welding seammight have serious and expensive consequences. Hence the need for awelding helmet thatmakes theweld process safer, more efficient, more accurate and more com- fortable. Why settle for anything less? www.thuthukawelding.co.za

New slim nozzle torch body F ronius has developed a new torch body for robotic welding: the MTB 350. This gas nozzle has a diameter that is 20%smaller than conventional torches, enabling improvedaccess to components. Owners of the Fronius TPS and TPS/i

Despite the slim gas nozzle, the new torch body enables a high duty cycle at maximum output: at 350 A when using pure CO 2 , the welding torch achieves a duty cycle of 60%, that is, the arc can operate for six minutes out of every 10 – and 300 A, this torch can weld without interruption. If mixed gas is used, the MTB 350 can achieve a 100% duty cycle at 250 A and 60% percent at 300 A. www.fronius.com

robotic welding devices can retrofit the new MTB (machine torch body) 350. The gas nozzle’s diameter is now just 20 mm, as opposed to the conventional 25. This means the welding torch can reach the welding seam more easily, even when working with challenging component geometries. The MTB 350 torch body is available in various geometries (22°, 36° and 45°) and is also available as an Asian-style variant with a longer torch body to suit typical Asian designs of robotic welding torches.

Traditional welding torch.

in all four classifications: • Optical class: Class 1

MTB 350 robot-welding torch.

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August 2018

AFRICAN FUSION