Harald Lemke. Courtesy of NanoSteel

Getting equipment to a mine site, whether it be a 400-ton haul truck or a replacement tire, can be difficult to manage given remote locations and poor road access or harsh environmental conditions. Additive manufacturing, commonly referred to as 3D printing, offers mine operators the ability to create certain pieces of equipment they need onsite, which reduces costs and limits logistical headaches.

According to the definition set forward by the International Organization for Standardization, additive manufacturing is the “process of joining materials to make parts from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing and formative manufacturing methodologies.” Today the main application of additive manufacturing is for small repair parts. But Harald Lemke, general manager of engineered powders at NanoSteel, says this is only the first step. Lemke foresees a future where miners will be able to redesign and print new equipment onsite in reaction to the changing conditions of a mine throughout its life.

CIM: Tell me about NanoSteel and what you do there.

Lemke: At NanoSteel, much of our focus as a business is on the development of high-strength sheet steel for automotive lightweighting. Separate and distinct from sheet steel is the initiative that I lead which is powder-based alloy development [that is 3D printable].

CIM: Can you explain what engineered powders are?

Lemke: Think about examples of stainless steel, like a spoon or some other piece of kitchenware. These items are often made with sheet materials, which are stamped or formed to generate the pieces. If the forms are complex or materials are used that cannot be stamped or casted, then you use powders. And powders are like little particles which can be 20, 50 or 200 microns. You take these particles and arrange them via processes such as additive manufacturing to make the parts you want. The powder is “engineered” when we design the alloy to deliver performance properties such as hardness or ductility that are required for a specific application.

CIM: What is the value of additive manufacturing in mining today?

Lemke: Additive manufacturing has several value propositions such as the potential to shorten lead times and manufacture highly complex parts. However, additive manufacturing is still in general more expensive than traditional subtractive manufacturing, in particular when larger part sizes need to be manufactured.

Since most parts in mining are of larger and simpler geometries, nearly all OEM mining parts are currently manufactured via traditional subtractive manufacturing, such as casting with subsequent machining or other post-production processes. However, AM’s supply chain benefits can provide a decisive benefit. For example, a replacement part can be cost effective even if it takes one day to be printed with the powder bed fusion technology if the part is needed at a remote location where high downtimes are experienced. The most common AM application in mining — used primarily for repair applications — is another AM technology, namely laser deposition technology, due to its higher deposition rate. But overall, additive manufacturing can help to provide shorter lead times, lower inventory and transportation costs, and on-demand parts.

CIM: Tell me more about using additive manufacturing for repair parts on site.

Lemke: Today you can save 80 or 90 per cent of the original piece and just add a little bit on the contours to finish it up. This is the first step. But it’s insignificant compared to what the real potential is. I’m talking about making new forms, not only repairing a form that has already been [constructed]. At the end of the day, the transformative nature of this technology is not there yet because a designer-driven manufacturing paradigm and process flow is still in its infancy. This is because only a few materials are available that can be printed reliably. Printing machines are still slow and expensive, and post-processing is still sub-optimal. For printing machines to be effective it is estimated that the machines need to be 10 to 20 times faster than today and it might take another five to seven years until such rapid and reliable production techniques are commercially available.

CIM: Can you give me some examples of what can be designed today using additive manufacturing?

Lemke: Currently, market innovators design and manufacture prototypes and a few parts such as novel pumps, impellers, filters, screens and heat exchangers. Heat exchangers benefit from additive manufacturing in particular when they feature less pressure drop and thereby lower energy consumption. All of these parts can be [created] on site if you have a printer and appropriate post-processing capabilities, assuming that you find a material that meets your performance requirement. Another example is if you have a stop in production, you can print the part right beside your facility. So the supply chain strategies are very important and you find that sometimes you can make short-term fixes for production with additive manufacturing and then later on if you want to have a certified part, you could fly that in.

CIM: What are the benefits of additive manufacturing from a logistics point of view?

Lemke: The breadth of logistic benefits increases when several parts can be redesigned to make one part, or if you can print a part that provides not only mechanical benefits but also improves heat transfer rates by printing complex cooling channels. You can also precisely calibrate part characteristics mechanically, thermally and electronically. And then once you have [the 3D model], you have a model history and now any change you make can be implemented more quickly and uniformly across an organization by changing the 3D model rather than each drawing. For example, your models might be developed in corporate engineering but the local applicator in Ohio, Alaska, or Saudi Arabia will customize it to his local needs. And with that decentralization, you don’t need to move 20 tonnes of steel with a helicopter, you just print it on site. Delocalized manufacturing is a significant advantage of additive manufacturing. You also don’t need so much decentralized inventory; you print it when it is required on site.

CIM: Does additive manufacturing make sense for all types of mining operations, no matter the location?

Lemke: The supply benefit is of course at remote locations, or in countries with political stability issues. But the location is just one driver. Another driver is innovation around process approach that can increase return on investment. For example, in high-value streams like gold, diamond, copper and nickel mining, when you can change the percentage of extraction of a mineral by one per cent – and you can do that often by proper mixing, heat control and process routing – you make tens of millions of dollars by timely optimising hardware to the current and local asset stream environment. That is where you have the benefit. You can redesign mission-critical process steps that are value adding according to local, spatio-temporal environments.

The mine changes, the composition changes, the minerals change. And you now have a manufacturing process that can immediately adapt and maximize the profit of an entire plant operation. But that requires visibility and adoption with regards to acceptance of these tools and a designer-oriented process flow thinking with localized monitoring.

CIM: What needs to happen for the adoption to occur?

Lemke: [Mining needs to move] away from asset thinking to profit-driven processes across disciplines, functions and silos. It’s an organizational question. The need, in my opinion, will be for supply chain managers that can integrate these new disciplines and technologies like additive manufacturing into daily operations.