The commercial vehicle superstructures from Moser, based in Switzerland, have to withstand enormous loads in tough construction site conditions. When it comes to welding steel and aluminium sheets for the dumper and loading systems, Moser has been using Fronius welding systems for 24 years.
Moser manufactures vehicle superstructures for trucks with a total weight of between 18 and 40 tonnes, with 40-tonne trucks capable of taking more than 25 tonnes of payload.
Stefan Rolli, operations manager at Moser, said: “The highest possible transport volumes per trip are the top priority in our industry. To enable our customers to transport as much material as possible with a specified total weight, we design our dumpers and loading systems to be as light as possible – without compromising on strength, durability, or user-friendliness.”
Depending on the size and number of axles on the vehicle in question, the truck superstructures produced in Steffisburg usually weigh between 3 and 4.5 tonnes. “The benefit in terms of payload for our customers from using our lighter superstructures compared to competitors is often between 500 and 700 kg per trip. This results in much more efficient use of the vehicles in line with our motto ‘Always one load ahead’,” Rolli added.
Currently, Moser uses around 35 Fronius welding systems in Steffisburg. These include the Fronius VarioSynergic 4000, the VarioStar 457, the TransSynergic 5000, plus the Fronius TPS 500i since 2018.
“Speed and flexibility in manufacturing are crucial for us, especially in the current situation. By using the Fronius TPS 500i and its welding characteristics, we have significantly increased welding speeds in all key areas. At the same time, there has been a noticeable reduction in the amount of rework required on the welds. Overall, the TPS 500i not only makes the welding processes considerably more efficient, but also the downstream work steps, which subsequently has a positive effect on our entire manufacturing process,” Rolli continued.
The welding specialists at Moser frequently use the PMC Fronius Welding Package in the PMC Universal, PMC Dynamic, and PMC Mix variants on their TPS-500i devices. PMC stands for Pulse Multi Control and is a further development of the pulsed arc.
Fritz Loosli, the application engineer and customer adviser at Fronius responsible for Moser, said: “In general, the PMC characteristics feature a stable, dynamic, and low-spatter pulsed arc. The excellent welding speeds of the TPSi are made possible predominantly by their high processor performance and the corresponding measuring and control speeds.”
The PMC characteristics provide two stabiliser and two correction parameters: an arc length stabilizer and a penetration stabilizer, as well as arc length control and pulse correction.
The welding specialists at Moser use the PMC Mix characteristic, among others, because it permits the welding of vertical-up seams without the usual oscillating motion. Overall, up to 40 percent faster welding speeds are possible with the PMC Mix process for vertical-up seams. The technical basis for this characteristic is the process change between a pulsed and dip transfer arc, i.e., the cyclical change between a hot and a cold supporting process phase. The heat input into the material is reduced by this process.
Steel Root is another characteristic that is often used by the welding specialists at Moser AG. This characteristic is said to bridge gaps of 2 to 3 millimetres in size when welding dumper parts. A soft and stable arc is a typical feature of the Steel Root characteristic. The detachment of relatively large droplets creates a viscous weld pool, which can be used to weld larger gaps with ease.
The PMC Dynamic welding characteristic is used at Moser for horizontal fillet welds. It delivers a relatively aggressive arc with high pressure and concentrated focus. It is said to offer high welding speeds with low energy input enable low-distortion welding results and save resources such as gas, filler metal and working hours.
Aside from this, Moser still uses standard arcs for many welding processes. As a rule, aluminium parts are welded with a conventional pulsed arc.
Additionally, it is essential for the welding specialists at Moser to be able to make adjustments on the welding torch.
“Dump trucks are components that can’t exactly be moved back and forth quickly and easily, so our employees move around the components. To give our welders maximum freedom of movement, all our welding systems are equipped with 10 meter-long hosepacks,” Rolli continued.
The welders use lightweight PullMig welding torches in the JobMaster version with their TPS-500i devices. The water-cooled welding torches are equipped with a small electric motor in the torch handle, which ensures smooth wirefeeding through the 10 meter-long hosepack.
With the “EasyJob” JobMaster setting, users have the option of saving up to five welding jobs directly on the welding torch and rapidly switching between individual jobs. Being able to call up all the important welding jobs for their daily work directly on the welding torch means they save themselves numerous trips between the welding system and the component.
“The ongoing technical developments, such as the TPS 500i most recently with its welding characteristics, contribute significantly to our performance, especially in terms of the speed and flexibility of our manufacturing process. The welding systems from Fronius help us to provide our customers in the Swiss construction site sector with the quality they rightfully demand from us,” Moser concluded.
