Welding is integral to the automotive manufacturing process and, in this regard, Malben Engineering, an award-winning supplier of welded assemblies to original equipment manufacturers (OEMs) and tier 1 automotive sector suppliers, has invested in a technological step-change over the past three years.
Malben Engineering makes use of automated robotic welding in its production of welded assemblies for the automotive sector.
Operational Director, Luca Smargiasso says the introduction of a new vehicle model by a key customer necessitated the introduction of new, completely automated welding technologies. These include adaptive pulse welding, dc projection welders, and controlled voltage spot welders; as well as advanced variable pulse MIG welding technology.
Data-driven welding processes
Malben Engineering’s welding processes, backed by extensive quality controls, deliver 750 000 projection welds and 1.7 million spot welds monthly. The company complies with the automotive sector’s CQI 15 quality standard – and was one of the first tier 1 suppliers to achieve an A-rating and green status – maintaining a zero margin for defects and a rejection rate of zero parts per million (PPM), significantly exceeding customer expectations.
Although Malben has welded coated and uncoated mild steel automotive parts for decades, Smargiasso says the automotive industry is using thinner gauge, higher tensile steels, which makes welding more challenging. “There is a drive to go thinner with stronger materials, to reduce weight and improve fuel efficiency.”
Malben’s automation and attention to detail deliver predictability and consistency. “In this sector, we are doing production welding for mass production runs. So, our welds must be exactly the same, every time,” says Quinten Ballot, Head of Maintenance, who has extensive welding experience.
Over the past eight months, Malben reports zero rejections. Smargiasso comments: “It is like climbing a mountain. Everybody can do day one, most people can do day two – but from day three, they cannot continue and are in danger of falling! It is being able to do the same thing day in, day out, over an extended period and without letting your guard slip, which really counts.”
Robust design of experiment processes and analysis of live data in real-time are factors that set Malben Engineering apart.
Plant Manager, Jithin Kottikkal explains that the quality of the data provided enables the Malben welding team – which collectively has some 70 years of welding experience – to take action when necessary to ensure that quality controls remain within limits.
Quality Control Manager, Cheslyn Reid adds: “We analyse the data, ensuring that it leads us in the right direction. We do not go into anything blindly, but we carefully analyse what our process tells us – tracking it over a certain period, then implementing production line changes to ensure sure we are always ahead.”
Ballot points out that strict process controls and team-based decision-making are also priorities.
Real-time adaptive welding
The real-time control of weld parameters is achieved by using pulse welding. The welding parameters are adjusted in real-time during the weld process. If the gap between the welded parts varies due to dimensional tolerance allowances, the weld voltage and arc length are adapted accordingly.
Technical Director, Marco Smargiasso says an important part of the Malben step-change was a move from ac to dc, with the move to dc projection welders, He notes that that where robotic spot welders are still controlled by alternating current, this is carefully checked: “We monitor and measure the voltage. If there is something wrong, the process is immediately stopped. Monitoring current ensures we do not get a cold weld.”
Ballot makes the point that the quality of welding that Malben achieves, also relies on highly skilled team members. “Malben employs experienced welders and builds skills within the company to keep pace with technology and with the requirements of our customers,” he says.
For more information visit: www.malben.co.za/
