CGI diesel block

Solving the Hard Case of Harder Iron

Nov. 16, 2023
Seco Tools researchers found a way to extend the performance life of tools by up to 20x, to machine high-strength, lightweight compacted graphite iron diesel engine blocks for Scania.

Stockholm-based Scania manufactures trucks and buses for distribution worldwide, and it’s also well-known for the quality and reliability of its diesel engines. The availability of new, lighter grades of cast iron – compacted graphite iron, or CGI – was a breakthrough in engine design, but before adopting it the Swedish manufacturer had to address a critical concern: Would existing machines and tools be able to work on this new material? If not, how would Scania manage their production process?

“The background was this new form of cast iron, which offered many advantages – it is more environmentally friendly and it’s also stronger, which means that they can make the engine walls thinner and lighter,” recalled Seco Tools’ Stefan Frejd, R&D Specialist, Drilling. “The problem that Scania wanted to explore was the fact that this material increased the wear on the production tools, which of course shortened the life of the tools.

“The challenge was to find a way of extending the tool life for the milling cutters, drills, and reamers that would be used on this new material.”

A project group was formed – and its work paid off almost immediately. “We got together with Scania’s engineers and discussed some of the problems and the applications they used, and then we came back with some new tools to be tested,” Freid explained. “The first drilling tool we tested turned out to have a tool life of more than 20 times the existing one, so that was a huge improvement.”

Other test tools managed to outlast their predecessors by a factor of seven, which represented a huge breakthrough for both Scania and Seco.

“A lot of these things come down to time – the tools last longer, which means that more time elapses between when you mount the tool and when you have to replace it. In practical terms, that means that you might mount a tool at the start of one shift and you can continue using it right through another shift before having to replace it, whereas previously you might have had to replace the tool at the start of each shift, which costs both time and money to do,” according to Frejd.

“What is often overlooked is that every time we change a tool the machine has to be stopped, and during that time it cannot produce anything, and time is money in manufacturing. The fact that we were able to make stronger, more durable tools also reduced the amount of breakage in production – when tools break during a shift it can often cause great disruption to the production process, and they take time to fix,” he continued.

The insights gained at Scania can be implemented in a variety of other settings, according to the Seco Tools specialist. “Every application is different, but there are always things that we discover that we can apply elsewhere. Normally you develop a tool from a stock item or a standard tool, and then you apply different criteria based on what the customer needs.

“In the case of Scania, they had particular requirements for roundness when reaming, for example, so you could say that their standard is in fact customized special tools.”

For Frejd and his team, the learnings and discoveries came about due to their close relationship with the customer – and the desire to understand and find a solution to their issues. “The most important thing for us in R&D is that ability to cooperate with production engineers in different companies – as with Scania there are always problems to be solved, but when we come together, we often find that we can do so quite quickly when we work together.”

Latest from Cutting Tools