Berco, part of the thyssenkrupp Forged Technologies Business Unit, is continuing to innovate within the undercarriage component market segment, with Francesco Grenzi, Executive Director of R&D, talking up some of the company’s most recent solutions for demanding applications like mining.

With over 100 years of experience and expertise in the industry, Berco says it manufactures and supplies undercarriage components to the world’s leading heavy machinery OEMs and to the aftermarket.

“Universally renowned for the very high quality of its products, Berco’s reputation is further bolstered by its dedication to providing tailor-made and innovative solutions for applications that operate in both unique and extreme conditions,” Grenzi says.

A recent challenge for Berco has been that of extending the number of hours of its mining excavator application.

“Because of the work efficiency of the most advanced mining excavators, as well as the extremely different working modes used in the open-pit mines, the goal of achieving 20,000 maintenance-free hours was indeed a difficult one,” Grenzi said.

The traveling rate of an undercarriage is also something that can significantly vary between applications. When blasting is being carried out, for example, the heavy machinery will naturally be evacuated from the area before detonation. In situations such as this, the use of carburised bushings is recommended to reduce the speed of wear.

For applications that do not travel frequently, however, undercarriage parts are still often subjected to wear. Continuous hammering of the front shovel, for example, may not lead to quick wear of the bushings, but can cause other side effects such as cracks on bushings.

Berco’s solution in this case was to use both quenched and tempered, and induction hardening and tempering bushings, as well as a quenched and tempered steel with boron to increase hardenability. These specially produced bushings deliver even more added value when fitted on reinforced chains, Grenzi said.

This solution, which is designed for heavy application such as for track chains used on 200-400 t machines, provides high resistance to wear as well as outstanding resistance to impact, according to Grenzi. Being capable of achieving up to 20,000 hours of use in the field, it ultimately reduces ownership and undercarriage costs. Since November 2020, they have been fitted as original equipment on two of the machines the manufacturer has built to perform in Russia’s most extreme environments.

While heavy machinery manufacturers look to Berco for tailor-made solutions, the company goes one step further by placing a large emphasis on R&D to anticipate solutions that are ever-more innovative, Grenzi says. An example of this is the use of ‘rotoforged’ steel in the production of rollers for very demanding mining applications.

This pioneering process will bring significant benefits to machines that have a huge load transfer in their working times, such as mining excavators that weigh above 200 t. For applications of this size and even heavier (350-400 t), the rollers are under pressure as they take all of the inertia of the vehicle. This means that the rollers need to be made of “perfect steel”, which is why the ‘rotoforging’ process is ideal, according to Grenzi.

Steel that has undergone this heat treatment process acquires a high microstructure and compactness, to such an extent it is able to achieve toughness values double those of conventional steel, he said. Continuous casting steel is usually rolled. Rolled steel that undergoes the new ‘rotoforging’ process has its microstructure transformed down to the core, resulting in a much stronger and tougher structure.

“For this reason, rollers made from ‘rotoforged’ steel are suitable for machines which must operate in the most demanding environments around the globe,” Grenzi said. “They offer a very high level of reliability of between 15,000-20,000 hours. This innovation is now ready to enter production.”