A leader in mineral processing sector, Weir's foundries are the cornerstone of the company's operations, according to Lee Jenkins, Director of Operations at Weir's Todmorden foundry.

The manufacturer of Warman® slurry pumps has six foundries, each supported by machine shops, strategically located in major mining regions, each with unique capabilities to service the local markets.

Across these sites, Weir has an installed capacity in excess of 50,000 tonnes a year, with the heaviest cast single piece produced weighing about 17 tonnes, while the smallest is 2.8kg.

In Latin America, there are foundries in Jundiai, Brazil and Santiago, Chile. They are currently increasing the capacity at the Jundiai site, while the Santiago foundry recently completed a melting upgrade, which includes some manipulation in the post-cast operations for robotic fettling.

There are also two facilities in Africa: the heavy bay foundry in Port Elizabeth, South Africa where a new sand distribution system was recently installed, including chromite separation and secondary reclamation USR technology, which gives an unrivalled sand quality. The facility in Isando, Johannesburg is focused on smaller Replicast components and has recently completed a major investment in the Replicast technology, as well as upgrading its melting units.

The two largest facilities are located in Todmorden, UK and Artarmon, Australia. Both share some common processes, including large, state-of-the-art shuttle-based moulding systems. The Artarmon site also has a team of applied materials engineers and technologists, allowing Weir to design and develop its own alloys. These world class laboratory systems operate in parallel with the large manufacturing facility, allowing Weir to assess items in a production environment.

The Todmorden facility has established the Digital Academy, which embraces Industry 4.0 through both the manufacturing and MRO (maintenance, repair, and operations) cycles. It has embraced the latest technologies – AI, machine learning, digital twins, advanced robotics and IIoT, amongst others – to train the workforce of tomorrow, provide solutions to its customers and remove the non-value-added elements from the process.

Digital Academy

The success of the Digital Academy means that, despite being a young science in most manufacturing facilities, additive manufacturing is now a very mature technology at Todmorden and printing patterns and tools has become part of its everyday operations.

Expanding on these capabilities, Weir set out to print certain aspects of specific components in sand to improve the accuracy and on-site safety. This allowed Weir to expand its offering from two product lines to 80 product lines.

On the back of this success, the team began exploring other laser scanning opportunities. Because of the accuracy of the technology, Weir is able to guarantee that the component will function correctly hydraulically when it arrives at site – something that’s never been more important with so many of its customers located in remote areas and at a time when there are supply chain challenges.

Weir introduced a metrology-grade 20 laser line scanning system, allowing it to produce a single-skin image in a fraction of the time than it would otherwise take. From there, the team continued to leverage this technology.

Now, every product comes as a 3D image, which is uploaded into the foundry’s systems. The 3D image can then be manipulated to produce a toolpath for additive manufacturing tooling. Weir is now installing the largest large-format printing system that’s commercially available at its Todmorden facility.

This technology allows Weir to print the tool in a recyclable material at 50% lower energy consumption. Moreover, the robot corrects itself, so if anything goes wrong it simply re-machines it without any operator intervention.

Once the pattern has been extruded and printed, the materials are laid out so quickly that they then need to be machined back to size. The robot simply drops the extruder head and picks up a machine attachment and does the final machining in a fraction of the time that it would take someone to do it.

The team is now investigating whether this technology can be used to subtractive manufacture one-off prototype items that can be used in test campaigns. This robotic sand milling concept would deliver an item at about one fifth of the cost it would take to additively manufacture it. The same robot used for printing would, instead, pick up a milling head attachment and mill the shape out of a blank sand block. This will provide an unrivalled route to market.

Sustainability

Sustainability is core to Weir’s purpose and is a critical priority for the mining industry. Its target is to achieve a 30% reduction in absolute CO₂e scope 1&2 emissions by 2030 from a 2019 base year. Weir’s overall approach focuses on energy efficient initiatives in hot spots, particularly the foundries.

Weir has partnered with ENGIE Australia and New Zealand to source renewable energy for its Artarmon operations. From the second half of 2023, about 50% of its energy came from renewable sources (solar farms located in New South Wales). This year it will be offset 75% of its CO₂e emissions from electricity and next year it will offsetting 100% of its CO₂e emissions. Weir already has solar panel installations in South Africa and Artarmon and is also planning to install solar panels at Todmorden facility.

Furthermore, Weir is focused on reducing the waste streams of sand, metal scrap, elastomer scrap and dust, with the aim to minimise or even eliminate sending waste to landfill.

The Todmorden facility is looking at recategorising sand – it’s biggest waste stream – to a low value product. It’s partnering with academic institutions to transform the sand from a waste product into a low-grade concrete product.

Moreover, all the foundries generate heat via melting and heat treatment. There are several projects looking at heat harvesting and then redistributing it, possibly for combustion purposes.

The foundries are the cornerstone of Weir’s operations, integral to its ability to service its customers reliably and in a timely fashion and central to its commitment to make mining more sustainable.

*This article was first published in International Mining, June 2024, titled: Prepared for impact