The ACO2-Save initiative: Ensuring the sustainability of joining technology

Sustainability is a major priority for the fastener manufacturer, ARNOLD GROUP. This is particularly true for e-mobility and electric vehicles where lightweight engineering is critical.

In fact, sustainability, e-mobility, internationalization, lightweight engineering, and digitalization are currently the company’s five defined strategic areas of focus. ARNOLD has focused its experts on determining the specific carbon footprint of each product by examining the whole value chain and cumulating the emissions of all supply-chain members.

To this end, ARNOLD has launched the ACO2-Save initiative. The program provides active support to customers in reducing CO2 emissions by designing and using fasteners and cold-formed parts in a sustainable manner.

At the beginning of product-development phase, an accompanying CO2 calculation is carried out. So, when a customer requests ARNOLD to make a part, the product carbon footprint can be determined using a specially developed CO2 calculator, after which optimization can be carried out jointly.

The objective at the end of the development process is to have a technically high-quality product that is cost and CO2-optimized. The design process includes the following steps:

• CO2-optimized engineering through digital forecasting tools
• Analysis of CO2 optimization by potentially making a change in the production technology or in the joining technology
• The use of innovative joining elements or systems

As one example, a special screw made of aluminum — with a volume of 8,733 mm3 and a weight of 23.58 g per piece — was previously produced by traditional machining. For production, a turned part blank was used that had an initial volume of 25,630 mm3 and 69.2 g per piece.

After an ACO2 Save analysis, this part was changed over to a formed part from the Conform Next product line. The result: after optimization, the forming blank has a volume of only 9,135 mm3 and a weight of 24.82 g per piece. In addition to the significantly optimized cost due to less material being used in cold forming, this has a considerable impact on the product carbon footprint of the special screw.

Now, if we consider the global developments in the automotive industry, the weight of new passenger cars and light commercial vehicles has risen in recent years. Specific to Europe, it has increased  from approximately 1,268 kg in the year 2000 to 1,360 kg in 2010 and about 1,420 kg in 2020.

The trend toward and demand for more hybrid and electric vehicles is likely to intensify because an EV weighs on average 300 kg more than a vehicle with a conventional engine due to the weight of the battery alone.

However, thanks to ACO2-Save and the associated changes to production technology of the “special” fastener, the CO2 emissions caused by this screw during production were reduced by as much as 45 percent.