August 2023 Volume 5

ENERGY

On the one hand, the demands include quantifying the Product Carbon Footprint (PCF) of supplied components; on the other hand, continuous measures for reducing the PCF are being called for [Fig. 1].

Fig. 2: Impressions of FRED The result for this typical closed-die forging reflects the basic characteristics of many forged components. The material used makes up the largest proportion of the PCF. In second place comes heat treatment, followed by heating to forging temperature. A factor influencing the proportions is whether the steel comes from the crude or electric steel route, or whether, for example, aluminum is used. Other influencing variables include the forging temperature and whether any heat treatment is carried out at all after forging. However, the various potential constellations mean that is impossible to establish a general rule of thumb. Instead, the FRED analysis based on industrial data is absolutely essential in order to identify potential ways of reducing the carbon footprint. EMMA: Workshop “Emission-free Manufacturing of Forgings” The path to reducing or even avoiding CO₂ emissions involves green electric power. This makes it possible to produce steel without CO₂ emissions via the direct reduction route using green hydrogen, via the scrap electric route, or by adopting completely new approaches3. Also conceivable are electric (re-)heating processes, e.g., for open die forging, rolling or for heat treatments in the forge or steel mill. Alternatively, hydrogen4 can be used, or else methane, which is synthetically produced from electricity. Similarly, heating processes in drop forges are now mostly inductive, so green electricity could avoid CO₂ emissions here, too. However, it is also clear that completely moving away from fossil fuels for material production will entail significant investment and operating costs. Likewise, converting today’s gas-based heating or heat treatment processes to hydrogen or electric power will also incur high costs. Accordingly, it makes a lot of sense to develop additional ideas for increasing material and energy efficiency, as these can, at least in part, offset the higher energy costs of the future, thereby rendering the transition to CO₂-free manufacturing more economical. By being able to calculate CO₂ emissions for various forging process chains, the groundwork is laid for evaluating ideas on how to reduce emissions. Accordingly, a workshop was held in November 2021 in which 60 participants from 43 companies and 13 research institutes developed ideas for reducing CO₂ emissions using

Fig. 1: Stakeholder demands on the manufacturing industry. The forging industry in Germany is proactively addressing this challenge together with its partner industries. Thus, in December 2020, the “NOCARBforging2050” started. Its first result was FRED. FRED – Forging Footprint Reduction Tool In the first phase of this project, the FRED tool has been developed to calculate the PCFs for forged parts. 50 companies both from the forging as well as partner industries have participated in this. FRED is designed as a web application. To calculate a PCF, some basic data is entered: component weight, electrical power mix used, PCF of the starting material and some other information. Users then enter the individual process sequence of their product. For these processes, the specific consumption of electrical energy, gas and other materials is derived from a database. In addition, the unavoidable material losses are specified for the individual processes. This information is then used to calculate the amount of CO₂ emitted for the end product. Data on electric power and gas consumption as well as on the typical material losses were obtained during the project from the numerous participating companies and stored in the FRED database. Although there will certainly always be potential for refining the data, FRED provides uniquely detailed analyses for metalworking processes. Fig. 2 shows the login page, the input of basic data and of the process sequence, as well as an analysis result for a quenched and tempered yoke from the drive shaft.

FIA MAGAZINE | AUGUST 2023 13