Smart Parts

Additive manufacturing (AM) is clearly an enabling technology with major potential in terms of benefits such as lower material use, lower tooling costs and shorter lead times. The value of AM parts is expected to grow at a compound annual growth rate of 15 percent, from USD 12 billion in 2020 to USD 51 billion in 2030. This alone makes it understandable that Sandvik sees AM as a potential tool for optimizing global supply chains.

With its longtime world-leading position in metal powder and the widest range of AM alloys on the market, Sandvik has, since 2013, made sizeable investments into a broad range of AM printing technologies. In 2019 Sandvik acquired a significant stake in BEAMIT, the first AM hub in Europe. Together, both companies have leading expertise across the entire AM value chain.

The value challenge is that a simple replication of parts designed for welding or casting by AM will almost invariably result in a prohibitive cost, mainly due to the higher hourly production cost and more expensive materials. The challenging cost structure must be justified with substantial benefits. A business case for AM exists when it creates a unique advantage in terms of productivity, lead time or logistics, or enables a complex geometry that is not achievable with conventional processes.

The key tool to achieve this is topological optimization, in other words redesigning the part to remove any unstressed, non-functional masses and leaving only the structures necessary for transiting loads. This can cut back the weight of the component by 50 percent on average, and in some cases up to 85 percent.

Another key factor for the feasibility of AM is the number of components to be produced. The shorter the production run, the more relevant AM is because the economies of scale inherent in conventional technologies require large production quantities. Conversely, the possibility to eliminate most of the conventional tooling costs can be crucial in low volume parts.

Moreover, AM creates possibilities to ensure availability by reducing the risk of any existing parts supplier going out of business or losing interest in a low-volume part. End-of-life-cycle components and slow-moving items are less price-sensitive, so the cost premium linked with AM is less of an issue. The project also aimed to reduce spare parts inventories and net working capital by cutting back on unnecessary stock and avoiding minimum order quantities. Having AM closer to end users also helps to shorten supply chains, reduce lead times and trim logistical costs, including warehousing and customs fees.

Yet another major benefit is a significant reduction in lead time, on average 37 days. This means parts can be delivered around 50 to 70 percent faster, and also increases component efficiency, which leads to energy consumption reduction and performance enhancement.

A great example was a fuel tank cap where brass was replaced with aluminium, yielding a total weight reduction of 78 percent. The added benefits included branding with the Sandvik logo and having the part number printed on the cap.

Some challenges still remain to be tackled. A hydraulic manifold was light-weighted by 82 percent, from 36.55 kilograms to 6.65 kilograms. But despite the impressive results, successful field tests and positive feedback, the added cost was not viable.

What comes next? “The AM screening project is now advancing to its second phase,” Bhalgat says. “We will fine-tune the criteria and ignore parts approaching the end of their life cycle. This will leave us with some 5,500 parts with the most potential for a reanalysis.”

AM is a rapidly evolving technology and likely to expand significantly within the next 10 or 15 years.

Where does Sandvik see itself in all this?

“AM technology is evolving very rapidly and still has to develop a lot in order produce larger, faster and more consistent parts at an economical price,” Bhalgat says. “As an end user, the biggest challenge is to have a viable business case. The industry, including equipment and powder manufacturers, universities and other research institutions are working on the current limitations, and the technology is expected to mature in the next decade.

By then, we will be ready to use it at full strength. Ultimately the aim is to convert around 5 percent of our inventory, some 3,000 individual parts, into additive manufacturing by 2030.”