4Orange barrels and cones once more line the spring landscape in front of earthmovers and cranes as the construction season hits full swing. In welding and manufacturing shops across the country, fabricators face the challenges of building and repairing these large machines and others that are often referred to as yellow goods.
Yellow goods are machines that move earth and build the structures that shape our world. They include items such as cranes, bulldozers, mining equipment, front-end loaders, excavators, forestry machines and bridge building equipment. “Yellow” is appropriate as it signifies the caution required around work zones as well as the energy generated onsite as spaces are built or renewed.
Manufacturing and repairing such machines requires plenty of welding. Long seam lengths, uneven joints and thick base materials are challenges to be met and overcome. While these could be issues in any welding job, the size and scope of the challenges in the yellow goods sector make them especially difficult to overcome. Just getting into a position to perform a weld can be a challenge when working on large excavators. Thankfully, new welding equipment is making the job a little easier.
Streamlined equipment
Positioning is where newer technology can help. In manual welding, climbing in and out of a bucket just to change a weld setting adds time and possible safety issues. The
ability to change welding presets remotely is a feature in many new welding power sources. Recent torch designs offer the option to select job presets, but often those options cost extra.
Some companies put user comfort first by making the ergonomic torches with preset ability a standard part of the welding system. A good example is the Fronius TransSteel line where each welder comes with a lightweight torch that can cycle through job presets with just a click. Other torches are available if more optimization is needed, but as a standard option, this is a great time saver that keeps the operator in front of the weld longer.
Staying at the weld site removes the safety issues of climbing in and out of the bucket, pipe or wherever the welding is taking place, but that keeps the power source at a distance, possibly causing power loss and arc instability. New welders can auto-compensate for any power loss that occurs over longer lengths of cable, removing the need for short power cables and grounds. Precision weld monitoring is becoming more in demand, but that can add more complications and trip hazards in the form of sensors and the cabling they require. New technology, like fast reacting, specialized waveforms, however, allows for monitoring without additional leads and sensors. The idea is to get into position and just weld until the job is done.
Multiple layers
The yellow goods industry requires a wider range of thicknesses than other industries. Thick base materials, intricate parts and thin materials for fenders and cabin enclosures are necessary in almost every build. In the past, one machine could require two or more welding power sources. Technology-forward welders have the ability to weld everything from thin aluminum to thick-gauge steel in a single machine and meet the challenges that come with each application.
Thick structural welds often require multiple layers to fill large gaps and fit-up issues. The first layer, called a root pass, needs to be structurally sound, like a building’s foundation. Root welds use a lower power setting but still need to cover the joint without burning through. This vital weld requires good side fusion to prevent silicon entrapments and good root reinforcement along the weld toe to reduce stress risers. Like any foundation, a strong root pass is critical to the overall integrity of the weld. Modern welders can react quickly enough to detect possible burnthrough and other issues before they happen, preventing expensive rework.
The next layers fill any remaining gaps before the cap weld is applied. Fill layers need solid wall fusion and benefit from wave forms that minimize spatter and the silicon entrapments caused by an uncontrolled puddle. The final cap pass must reinforce the weld face and cosmetically adhere to the geometry of the weld design, such as being flush to the part or having extra reinforcement.
The cap weld needs to look good. Typically, this kind of root, fill and cap would require a lot of intensive rework, such as grinding and refilling to achieve a solid and appealing weld. Depending on the application, these multiple layers could require multiple welders to get the desired weld. However, new technology offers spatter reduction and stable arc consistency from root to cap in a single power source.
Automated options
But what about robotic welding? Some cranes and other equipment used in the yellow goods sector have yards-long seams that need to be welded. This is best done through
automation.
Arc control and consistency are key here, as well. Automation has its own challenges, one of which is maintaining a high-quality weld at production travel speeds. Fast reaction times inside the welder and auto-compensation work with precision weld monitoring to keep the arc consistent over long seams. Wobbles and starts/stops need to be minimized for proper quality, and this is where digital power sources, such as the Fronius TPS/i, excel. With the ability to perform manual and robotic applications, the TPS/i is a sound option for those looking for a versatile machine.
The idea of a do-everything welder seems like a dream, but there are a few on the market that can do most everything. They offer specialized welding, such as pulse, along with easy-to-use interfaces like touchscreens. While a touchscreen may seem out of place on a dirt-strewn job site, they are robust.
If that doesn’t suit the situation, models are available that will have the operator up and welding within four clicks of a knob. Building and repairing large machines with intricate parts offers a lot of welding challenges. Rest assured that modern welders will keep operators and workers safer and more comfortable without breaking the budget.
