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4 Steps to Optimizing Sustainable Design and Manufacturing

aPriori’s four-phase sustainability maturity model integrates sustainable practices into manufacturing while balancing profitability and environmental impact

This framework guides manufacturers toward environmental stewardship using data-driven insights to make effective design, sourcing, and production choices

Designing products that balance profitability and sustainability is essential in today’s market. This requirement is driven by a growing consumer demand for greener products, stricter environmental regulations, and a collective push to achieve carbon reduction targets.

Manufacturers must integrate sustainable practices into their existing operations without compromising on efficiency or competitiveness. This raises a pivotal question: How can manufacturers align their operations to promote environmental stewardship and spur growth?

To address this critical issue, aPriori has established a sustainability maturity model as a strategic roadmap for manufacturers to assess their current capabilities and the effectiveness of their green supply chain management initiatives. By monitoring their sustainability maturity performance, manufacturers can establish clear steps to reduce their carbon footprint.

The following figure illustrates how product development teams can assess and pinpoint their position across the four stages of sustainability maturity.

Manufacturers that don’t advance their sustainability maturity to the fourth and final stage risk falling behind their competitors and being saddled with additional operational costs due to incurred carbon taxes and other regulatory policies enacted to spur the reduction of greenhouse gases (GHGs).

Learn more by downloading the aPriori Sustainability Guide at get.apriori.com/CTI-mag

Stage 1: Create Precise, Auditable CO2e baselines

Creating an accurate carbon emissions baseline is the first step in achieving a sustainable and green supply chain. This baseline empowers sustainable manufacturers to measure and quantify the carbon footprint of their existing supply chain operations, enabling them to:

• Use their current “state of sustainability” as the starting point to plan and track their progress
• Identify and focus on the areas with the highest cost and carbon reduction potential.
• Set realistic cost targets that guide and influence product teams’ supply chain decisions.
• Adhere to environmental, social, and governance (ESG) standards and regulations.
• Benchmark and compare their sustainability performance against industry competitors.

Life cycle impact assessments (LCIAs) are a standard method to establish CO2e baselines and provide manufacturers with standardized emissions estimates for product lifecycle areas that are impossible to measure accurately.

Carbon assumptions for a product’s in-use phase can be entirely different from reality. A car, for example, could burn fossil fuels for 300,000 miles within the range of established fuel consumption values, or it could be written off in an accident after 1,000 miles. Similarly, a product designed for 90% reuse could still end up in a landfill and not achieve its optimal contribution to the circular economy.

An LCA is a great tool for making assumptions and using averages. How-ever, the manufacturing process doesn’t require that level of guesswork, so a more precise baseline would be beneficial for that phase. aPriori’s automated sustainability insights solution closes the gap by integrating data from ecoinvent, a leading third-party LCA and inventory database tool. aPriori utilizes ecoinvent’s database to quickly establish environmental baselines and Greenhouse Gas (GHG) emissions at the product level. With automated and more precise baselining, teams can quickly move to the second phase of sustainability maturity: evaluating and selecting sustainable suppliers.

Stage 2: Select Sustainable and Responsible Global Suppliers

Next, evaluate and select suppliers based on their local electricity mix, material supply, and processes (Scope 3). Procurement teams can create digital factories for each supplier to see each vendor’s carbon impact, and then compare vendors using the same production criteria (e.g., the same production volume, manufacturing process and equipment, etc.). Digital factories will also show how the energy mix and energy consumption of a supplier in India, for example, compares with production facilities located in Mexico and China. Product teams aim to enhance the sustainability of existing innovations through informed supplier selections instead of resorting to costly design or material changes. Sustainable sourcing offers the most straightforward approach to reducing CO2e by minimizing the need for extensive design changes, and therefore can be implemented at any time. However, it is difficult for product teams to capitalize on this opportunity without a dedicated and standardized tool such as aPriori.

aPriori provides manufacturers with complete visibility into the sustainability of their supply chain, through a digital twin of the manufacturing facilities at their disposal, empowering them to make data-driven sourcing decisions.

By utilizing aPriori for sustainable sourcing, companies can:

• Explore various “what-if” scenarios (regions, routings, materials, volumes/batches, suppliers, make vs. buy).
• Reduce iterations and negotiation by digitally connecting buyers and suppliers.
• Fill skills gaps with exposure to granular, actionable, real-world sourcing data.
• Identify sustainable procurement strategies to support internal ESG goals and initiatives.

Stage 3: Optimize Existing Products for Cost and Carbon

The path toward greener products involves optimizing existing product innovations. In stage three, product teams can consider alternative materials with lower carbon or higher recycled content. And they can also make processes more efficient to improve cost and environmental sustainability, or look to utilize renewable energy sources.

The objective is to minimize cost overruns and release products at target costs to maintain profitability and competitive advantage. However, this is difficult to achieve when cost engineering teams are limited to conventional, labor-intensive costing tools like manual spreadsheets. And the complexity of this challenge heightens when the situation extends to CO2e emissions. This is because spreadsheet-based solutions cannot:

• Evaluate the complex interrelationships between direct and secondary cost & carbon drivers in real time
• Accurately manage cost & carbon variables in an ever-changing global supply chain
• Identify and capitalize on cost & CO2e reduction opportunities during early product design phases

aPriori provides a precise, real-world product cost optimization solution to make highly informed and effective manufacturing decisions. aPriori’s cloud solution can simulate production based on product design (geometry), manufacturing overhead costs, direct labor hours, machine hours, and more. This capability can be fully automated through PLM integration.

Additionally, aPriori enables companies to navigate and manage rising material costs, inflationary pressures, and other external risks to build cost-effective products. aPriori also automatically notifies and provides actionable feedback to design, manufacturing, and sourcing teams when products exceed cost thresholds. This facilitates seamless collaboration among product development teams, enabling them to eliminate cost drivers early and maintain corporate profit margins proactively.

Stage 4: Remove Embodied CO2e Through Data-driven Product Design

The final stage of sustainability maturity represents the most challenging path and the greatest opportunity for reducing GHG emissions. Product engineers can typically compare multiple product designs and intuitively select the most cost-effective option for both cost and DFM. But when you add carbon to the mix, the answer is usually far from obvious.

But by using real-time CO2e feedback from the 3D CAD model, teams can proactively modify the product’s design to reduce its embodied carbon. They can also ensure that a product meets its targets for cost, DFM, and sustainability by selecting the option that best balances all requirements for sustainable design.

Take the Next Step to Optimize Sustainable Design

Optimizing sustainable design and manufacturing is not just a choice: it’s pivotal to addressing today’s market requirements and customer demands. aPriori’s four-step sustainability maturity model presents a comprehensive strategy for manufacturers to align their operations with environmental stewardship while enhancing profitability and market competitiveness.

aPriori’s four-stage model provides a roadmap for best-in-class green manufacturing based on strategic design strategies. It also underscores the need for data-driven insights to make effective design choices amid increasingly complex supply chains. Mature companies in this area will contribute to global carbon reduction efforts and position themselves as leaders because sustainability is increasingly a determinant of success. Once you have the capability for evaluating both cost and carbon during design, and leveraging the same data for sourcing or procurement, you can then start to include the “cost of carbon” as a strategic tool. Leaders in this space are utilizing an internal carbon price (ICP) to convert the units of measure from Kg of CO2e to currency. This is exactly how the Carbon Border Adjustment Mechanism, or CBAM is going to work from January 1st, 2026. This is why it makes a lot of sense to build carbon decision making into the same method as cost decision-making.

Furthermore, evaluations of a product’s cost are rarely left to assumptions or industry averages, but that is usually how the majority of product carbon footprint assessments are done. We all need to care as much about carbon emissions as we do cost. In 2024 alone, it is estimated that climate-related disasters wiped $2 trillion from our economy. That is more than the recession in 2008. In manufacturing, we have both responsibility, but also an opportunity to increase competitive advantage, by reducing the environmental impact of not only the use of the products, but the manufacture of them.

If you are interested to learn more about how you can combine cost, carbon emissions and manufacturability evaluations, based on 3D CAD data, get in touch via get.apriori.com/CTI-mag

The Automotive Industry’s Race to Zero Emissions

Mark Rushton, Sustainability Director, aPriori Technologies

Whether it is the end of the road for Internal Combustion Engines or not (due to synthetic fuels), the in-use phase of a vehicle’s carbon footprint will soon no longer be the most significant impact. Tackling embodied carbon proactively and cost effectively is how leading manufacturers are staying ahead of the competition.

Beyond Tailpipe Emissions

In the automotive industry, we are facing unprecedented challenges with the transition to emission free mobility. Innovation holds the key to success, but some innovations are too expensive to put into production. How can we try new manufacturing processes to get a competitive edge, without detailed cost and carbon footprint analysis of these new processes? Time could be lost experimenting. In this article, we will explore the 4 levels of product sustainabilty maturity that we have identified in customers and prospective customers of aPriori Technologies, from the Automotive Industry and beyond. It also explores various strategies to reduce the embodied carbon in automobiles.

External damping of roller bearings and its effect on the acoustics of an e-mobility gearbox

M.Sc. Kai von Schulz, M.Sc. Tilmann Linde, Prof. Dr.-Ing. Steffen Jäger
Furtwangen University, Institute for Product and Service Engineering

Reducing the sound emitted by the vehicle and the noise perceived by the passengers is an essential part of the development of modern (e-)vehicles. Bearings are crucial to the transmission of vibrations within the vehicle powertrain. This article presents a method for studying the impact of external bearing damping on acoustic properties. For this purpose, damping elements between the outer bearing ring and the gearbox housing of a gearbox used in electric vehicles are introduced, and parameters relevant to damping are varied by means of design of experiments.

Noise sources and sound transmission

At first, the noise sources that occur in a gearbox for electric vehicles will be identified. The gear mesh is determined as one of the primary sources of noise. The vibrations generated by the gear mesh are transferred through the shafts, the bearings, and the gearbox housing [1]. The design and material of the gearbox housing play a crucial role in how these vibrations are transmitted and whether they are dampened or amplified [2]. The vibrations can cause resonance in the housing, amplifying the noise emitted from the gear mesh. The air-borne sound emission occurs when the vibrations from gear mesh and structure-borne sound radiate into the surrounding environment. Due to deviations in the ideal meshing, a transmission error occurs between the driving and driven gear. The transmission error is primarily influenced by the manufacturing tolerances, variations in gear tooth geometry, and operational conditions such as load and speed [3]. The design and manufacturing quality of the gears have a considerable impact on their acoustic characteristics [4]. Moreover, the surface roughness of the gear teeth can influence friction and noise generation [5].

Bearings not only transmit the vibrations introduced by the gear mesh, but can also be a source of noise themselves. The primary sources of noise in bearings occur from various factors including design, manufacturing imperfections, operational conditions, and inadequate maintenance [6]. Factors such as load, speed and alignment are of significant importance. Imperfections in the surface finish of the raceways and the balls or rollers, as well as their roundness, can result in an uneven distribution of loads across the bearing surfaces [7]. The presence of high loads or speeds can exacerbate any existing imperfections in the bearing [8].

Finally, the electric motor can also be regarded as a source of perceptible noise. Electric motors, while quieter than internal combustion engines, introduce their own sources of noise, particularly through torque ripple and electromagnetic interference [9]. Torque ripple refers to the variation in torque output as the motor rotates, which can induce additional vibrations in the gearbox [10]. In addition, electromagnetic interference can cause vibrations in the motor’s components, which may be transmitted to the gears through the coupling, thereby further worsening the acoustic behaviour [11].

Potential noise reduction measures

Following the overview of the noise generation mechanisms within the gearbox, it is evident that specific, targeted measures are required to mitigate the associated noise emissions effectively. The primary noise sources, as described in the previous section, are main areas of concern. Targeted measures in these areas can significantly improve the acoustic behaviour of electric vehicle gearboxes. The authors have examined a wide range of measures for reducing the noise of drive systems [4, 12]. The focus of this article is on damping of the excitation by both the tooth mesh and the ball bearings.

The modification of bearing damping characteristics has the potential to result in a reduction in noise levels [13]. Incorporating damping inserts within or around the bearings of a gearbox is an effective method to absorb vibrations at their source before they are transmitted to the gearbox housing. Materials commonly used for these inserts include elastomeric compounds, viscoelastic polymers, and soft metals which are tuned to absorb specific frequencies of vibrations that are prevalent in gearbox operations [14]. These damping elements are usually placed in the most effective locations in the bearing assembly, where they can absorb the vibration energy resulting directly from the interaction between the rolling elements and the raceways.

Design of experiments on external bearing damping configurations

Design of Experiments (DoE) is a statistical approach to study the impact of multiple factors on the systems performance. In the context of analysing external damping of roller bearings, DoE is applied to evaluate how different parameter sets affect the transfer of the vibrations. DoE is particularly useful in this context, as it enables the identification of the most influential factors affecting both noise levels and efficiency, as well as the optimal combination of these parameters.

The variables in this case are the number of O-rings, their rigidity and the cord thickness of the O-rings, and whether additional oil is pressed into the gaps or not. By allowing simultaneous variation of parameters, DoE not only saves time and resources but also uncovers interactions between these parameters that might otherwise remain hidden. In this way, DoE provides a more comprehensive understanding of how the variables work together to influence the system’s behaviour, revealing possible synergies or trade-offs between different parameters. Here, the focus is on the system’s response in terms of its structure-borne and airborne sound emissions. Additionally, the system efficiency is analysed. For example, reducing the stiffness of the O-rings may reduce the transferred vibration, but it may also reduce efficiency due to a higher transmission error in the tooth mesh. The application of DoE allows the reduction of the number of experimental runs while maintaining the comprehensive coverage of the interactions and effects of all factors within the specified range. This efficiency in test design is critical in experimental research involving complex mechanical systems, where a large number of tests could be impractical due to time, cost, or resource constraints.

Physical study

To evaluate the presented measure of outer bearing damping, an existing high-speed gear test rig (cf. Figure 1) is being converted so that different parameter sets of outer bearing damping can be tested for their effectiveness under different operating conditions, such as speed and torque.

Fig. 1 Gear pair test rig.

For this purpose, the bearing seats have been modified to allow the use of up to three commercially available nitrile rubber O-rings. In addition, it is possible to fill the spaces between the O-rings with oil and apply an overpressure. Figure 2 shows a schematic illustration of the design.

Figure 2 CAD geometry of outer bearing damping design.

In this study, the experimental parameters are varied within specific ranges, providing valuable insights into their effects on system behaviour. Various tests are carried out at different torques and speeds in the range between 0 and 6000 rpm and 0 and 45 Nm. The measurement results are analysed at static operating points. The experimental design includes varying the number of O-rings from 1 to 3 and varying the stiffness of the O-rings between 70 and 90 Shore. In addition, the cord thickness of the O-rings is varied between 1.8 mm and 2.8 mm and whether additional oil is injected into the gaps is also considered as a binary factor (yes/no). Through the application of DoE, this study aims to determine the optimal combination of these factors to achieve an appropriate damping characteristic: significantly reducing noise while maintaining high efficiency.

Once the test rig has been converted and the measurement campaign has been completed, the most promising damping elements will be further optimised.

Authors

M.Sc. Kai von Schulz: Kai.vonSchulz@hs-furtwangen.de
M.Sc. Tilmann Linde: tilmann.linde@hs-furtwangen.de
Prof. Dr.-Ing. Steffen Jäger: steffen.jaeger@hs-furtwangen.de

References
[1] Tosun, M., Yildiz, M. u. Ozkan, A.: Investigation of Gearbox Noise and Comparison of Varying Transfer Path Analysis Methods. SAE Technical Paper 2017-01-1867, 2017
[2] Amaral, D. R., Ichchou, M. N., Kołakowski, P., Fossat, P. u. Salvia, M.: Lightweight gearbox housing with enhanced vibro-acoustic behavior through the use of locally resonant metamaterials. Applied Acoustics 210 (2023), S. 109435
[3] Heider, M. K.: Schwingungsverhalten von Zahnradgetrieben. Beurteilung und Optimierung des Schwingungsverhaltens von Stirnrad- und Planetengetrieben. Zugl.: München, Techn. Univ., Diss., 2012. Dissertationen der FZG / Forschungsstelle für Zahnräder und Getriebebau, Technische Universität München, Bd. 185. München: Verl. Dr. Hut 2012
[4] Schulz, K. von, Linde, T. u. Jäger, S.: Profile Modifications for Gears and their Effect on the NVH Behaviour of an Electric Vehicle Gearbox. 2024 Stuttgart International Symposium on Automotive and Engine Technology. Stuttgart 2024
[5] Zhao, X. u. Vacca, A.: Analysis of continuous-contact helical gear pumps through numerical modeling and experimental validation. Mechanical Systems and Signal Processing 109 (2018), S. 352– 378
[6] Adamczak, S., Stępień, K. u. Wrzochal, M.: Comparative Study of Measurement Systems Used to Evaluate Vibrations of Rolling Bearings. 1877-7058 192 (2017), S. 971–975
[7] Mohd Yusof, N. F. u. Ripin, Z. M.: Analysis of Surface Parameters and Vibration of Roller Bearing. Tribology Transactions 57 (2014) 4, S. 715–729
[8] Wang, Z., Yang, J. u. Guo, Y.: Unknown fault feature extraction of rolling bearings under variable speed conditions based on statistical complexity measures. Mechanical Systems and Signal Processing 172 (2022), S. 108964
[9] Gong, C., Zhang, P., He, S. u. G S J, G.: E-motor NVH Analysis for PWM Induced Current Ripples in EV Applications. 2022 IEEE Energy Conversion Congress and Exposition (ECCE). IEEE 2022, S. 1–5
[10] Novak, W.: Geräusch- und Wirkungsgradoptimierung bei Fahrzeuggetrieben durch Festradentkopplung, Universität Stuttgart Dissertation. Stuttgart 2010
[11] Kim, S. J., Kim, K., Hwang, T., Park, J., Jeong, H., Kim, T. u. Youn, B. D.: Motor-current-based electromagnetic interference de-noising method for rolling element bearing diagnosis using acoustic emission sensors. Measurement 193 (2022), S. 110912
[12] Schulz, K. von, Linde, T. u. Jäger, S.: Measures to reduce the noise emission of a gearbox for electric vehicles. Tagungsband Tribologie-Fachtagung 2024. 2024, S. 394–403
[13] Tsuha, N. A. H. u. Cavalca, K. L.: Stiffness and damping of elastohydrodynamic line contact applied to cylindrical roller bearing dynamic model. Journal of Sound and Vibration 481 (2020), S. 115444
[14] Turnbull, R., Rahmani, R. u. Rahnejat, H.: The effect of outer ring elastodynamics on vibration and power loss of radial ball bearings. Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics 234 (2020) 4, S. 707–722

A.J. Rose Installs World-Class Equipment in Response to Industry Trends

Electric vehicles are revolutionizing the automotive industry in a way that has not been seen since the seatbelt became mandatory in 1967. Competition among OEMs is increasing and the modern day ‘race to the moon’ is underway, lead by manufacturers such as Volkswagen, Ford, GM and Volvo as they roll-out EV & hyrbid models off the assembly line. Not to be forgotten are more than 100 ambitious startups looking to make a name in the automotive world. Take a couple steps back in the supply chain and there are countless automotive suppliers watching the competition unfold, excited for the new market opportunities this will bring.

Metal stamping companies make up a large part of the automotive suppliers wondering where they will fit into the electric vehicle landscape. Many likely wondering what their new identity will be 10 years from now. It is certain that metal stampings will remain a major part of the automotive supply chain as we transition to EV, but the type of components that will be stamped is the question mark. A reputable stamping supplier that once specialized in powertrain components may soon find their stamping presses being used for battery trays and EV motor laminations. In order to stay agile and be prepared for any type of stamping coming through the pipeline, a supplier needs two things: First, the the willingness and unity to change even if it’s outside their niche, and second, the necessary equipment and processes to support the evolution.

In the case of A.J. Rose Manufacturing Co., they recently invested in new equipment intended to support the markets of the future. That equipment is a newly-built servo press from Aida. This will be the 58th press at A.J. Rose and also the largest press at 1375 tons. At this tonnage, it opens doors to new markets and product lines with the ability to to produce larger parts and run thicker material. They are adapting to the market, not expecting the market to adapt to them. At a bed size of 191” x 70” and a 20 inch stroke, A.J. Rose will offer more capability to their customers looking for large stampings. A purchase of this magnitude was a decision based partly on current necessity and partly on strategic forecasting of future demand. A.J. Rose is positioning themselves to support the increased sourcings in battery plates, battery boxes, battery trays, large brackets and similar housing components that are becoming popular in the EV space. In order to be nimble in these new markets, the press will be capable of running transfer tools or progressive tools, and the servo motor allows for variable speeds and advanced forming capabilites, such as dwelling at the bottom of the stroke. These features make this a Swiss-Army knife of stamping presses, capable of forming metal into unique geometries in a wide range of size and thickness. This is what puts a supplier in a position for growth, making them attractive with an exisiting customer or one brand new.

A wide range of OEM customers turn to A.J. Rose for high-precision, high-quality metal stampings, therefore it is crucial to maintain their reputation as an innovator in the industry. Having such a reputation associated with their brand helps to establish credibility and lends to partnerships with up-and-coming EV startups. Out of many startups gaining momentum in the EV space, it will certainly narrow down to a short list of companies that rise to the top and begin serious competition in the pure EV markets.

A large pit is dug roughly 20 feet into the ground to prepare for the press. Supporting walls are poured from cement within the hole and a connection is made to the existing underground scrap-removal conveyer (right side).

A gantry system is used to support the weight of the press as it is assembled and secured to the foundation.

The press is assembled and secured in the pit. Capacitors are installed in the back.

Dog clutch without angular backlash

Gabriela Achtenova, Michal Jasný, Jiri Pakosta, Rômulo do Nascimento Rodrigues
Center of Vehicles for Sustainable Mobility, Czech Technical University in Prague

Dog clutches are cost-effective but often suffer from angular backlash, causing discomfort. A novel, patented design has been developed to eliminate this issue using a purely mechanical blocking mechanism. This design, fully interchangeable with conventional mechanisms, requires no extra modifications but needs an external synchronization system.

Featuring innovative gearshift dogs and blocking mechanisms, it was tested with two prototypes on test benches. The results showed the design’s effectiveness, and robustness especially for hybrid and electric vehicles, addressing key shortcomings of traditional clutches.

Introduction
Greenhouse gases, CO2 regulations, alternative fuels, and vehicle electrification are critical issues driving the rapid growth of hybrid (HEV) and electric vehicles (EV) [1]. This shift demands innovative solutions in automotive engineering. This research focuses on developing a new gearshift mechanism to meet these demands. In HEVs and EVs, the electric motor can act as an external synchronization mechanism, potentially reducing costs. Parallel hybrids, requiring a wide range of gear ratios, benefit from cost-effective gearboxes like manual parallel shaft gearboxes (MT) or automated versions (AMT) [2][3]. These gearboxes commonly use synchronizers, a prevalent gearshift mechanism in passenger cars [4].

This research aims to replace the synchronizer with a new, cost-effective gearshift mechanism that eliminates the need for synchronization while maintaining or surpassing the synchronizer’s functions [5]. Typically, a dog clutch is the simplest gearshift mechanism for constant mesh gears but has been limited by driving comfort and NVH (Noise, Vibration, and Harshness) concerns. In electric powertrains, NVH issues include gear whine and gearshift mechanisms [4],[6]. Reducing angular backlash is crucial for minimizing NVH, a feature of the new mechanism, while ensuring cost-effectiveness and compactness. More compact gearboxes tend to be stiffer, further reducing NVH [7].

This research introduces a patented dog clutch design addressing angular backlash, a common issue in traditional mechanisms [7]. Using a purely mechanical blocking system, it minimizes backlash and improves shifting quality. The form of dogs enables very fast disengagement of the speed even under load. Rigorous prototype testing confirmed its functionality, durability, and comfort, making it suitable for vehicle gearboxes.

Final design of dog clutch with blockchain mechanism

The clutch assembly (Figure 1) includes a hub (1) on the gearbox shaft, a sliding gear (2) that moves axially to engage gears, a gearshift sleeve (3) for controlling movement, and a blocking ring (4) to secure the sliding gear in positions. The sliding gear is split into two halves connected by screws (5) and pins (6). One blocking ring locks the sliding gear in all three positions (engaged/neutral/engaged) and secures the gearshift sleeve in neutral. No changes to the standard MT/AMT gear selector mechanism are needed. The design’s uniqueness is confirmed by Patent No. 307443[8] and the utility model „Schaltungskupplung“ [9]. Following design optimization, prototypes of dog clutches with a blocking mechanism were produced. Two clutches for the MQ200 gearbox were made to engage 1st, 2nd, 3rd, and 4th gears, see Figure 2. The prototype production was funded and supported by ŠKODA AUTO.

Gearshift process

The blocking ring stays concentric with the hub due to its constant contact with the sliding gear or gearshift sleeve. With six contact points, the ring maintains its shape during compression. To prevent uneven deformation, which could interfere with gear movement and cause excessive wear, the ring’s ends are bent inward. Figure 3 illustrates the gearshift process, where shifting the right gear involves:
Position 1 – neutral:Black arrows show axial backlash between the sliding gear and the gearshift sleeve. The blocking ring holds both components – sliding gear (upper) and sleeve (lower) – in neutral;
Position 2 – engagement preparation:The sleeve moves right, compressing the blocking ring, while the sliding gear remains in neutral until backlash is resolved;
Position 3 – engagement in process:With backlash removed, the sleeve pushes the sliding gear right, and the blocking ring stays compressed;
Position 4 – engagement termination:The sliding gear reaches its maximum position, engaging the gearshift dogs. Both components stop moving axially, and the blocking ring is no longer compressed;
Position 5 – engaged: The blocking ring expands back to its original position, fitting into the sliding gear’s groove, preventing clutch disengagement due to torque;

Position 6 – disengagement preparation:The sleeve moves left to compress the blocking ring. Axial backlash is present, keeping the sliding gear engaged;
Position 7 – disengagement in progress:The blocking ring is fully compressed, backlash is gone. The sleeve moves the sliding gear to
Position 8 – Disengagement Termination: The sleeve reaches neutral, but the sliding gear remains slightly engaged due to kinetic energy. The decompressing blocking ring helps move the gear to neutral;
Position 9 – Neutral:The dog clutch returns to the neutral position, same as Position 1.

Prototypes of the clutch were designed for the MQ200 gearbox, where the blocking ring withstands axial forces up to 2 kN during dog engagement, transferring a maximum torque of 200 Nm. The force needed to engage and disengage the clutch via the gearshift sleeve is about 45 N, which is well within permissible limits and comparable to manual shifting forces. The sliding gear and gearshift sleeve have been optimized for powder metallurgy. For the sliding gear, only grooves for the blocking rings and threads on one half need machining, while the gearshift sleeve requires machining of the inner groove for the neutral position. The outer groove, for the gear selector fork, is for prototype compatibility and can be omitted in future designs. No additional parts are required between the sliding gear and gearshift sleeve, ensuring concentric alignment with the hub. The blocking ring is fixed securely and cannot rotate around the shaft axis due to the pin.

Verification of the dog clutch

The fulfillment of the requirements for the dog clutch with a blocking mechanism needed to be validated against the design specifications. First experiments were static to verify the shift force and unwanted disengagement. The resulting gearshift force required to compress the blocking ring was measured to be 45 N.

Further was experimentally tested that the blocking ring functions as intended, preventing unwanted disengagement of the clutch.

The dynamic tests were dedicated for verification of function and for endurance tests. The first phase of clutch prototype testing used an inertia test bench with the output shaft connected to a large inertia disc. Tests focused on smooth shift sleeve movement and proper engagement / disengagement of the dogs. No unexpected behavior was observed.

The gearbox was connected to the gearshift robot on the inertia test stand, and gearshifts were performed with various input parameters. Mismatch speed was controlled by the difference between the stationary input shaft and the rotating wheel or by gear ratios between two gears. Figure 4 shows data from a gearshift with 3rd gear engaged at a mismatch speed of 30 RPM. The gearshift process began at 0.96 s, with rising displacement and force curves. A sharp drop in force at 1.02 s indicated compression of the blocking ring, allowing the sliding gear to move. The force increased as the dogs engaged, and by 1.08 s, engagement was complete. The gearshift took about 60 ms.

To proceed with dynamic check of the blocking mechanism, the gearbox was moved to dynamometric test bench. The function for the 3rd and 4th gears were performed with positive result. Due to test bench capacity 1st and 2nd speed were not tested.

Service life (endurance) tests were conducted for the 3rd and 4th gear clutches on the inertia test bench, with each gear being shifted 180,000 times and the gearbox output set to 89 RPM. This low speed simulated a mismatch speed of around 140 RPM, optimizing the gearshift process and eliminating the need for external synchronization. Each shift took just over 2 seconds, resulting in 220 hours of continuous testing per clutch and blocking ring.

Conclusion

The new patented dog clutch with a blocking mechanism enhances efficiency and reduces costs for electric and hybrid vehicles. It offers minimal angular backlash (less than 0.1°) and can disengage under load, improving shifting comfort and torque transmission. This purely mechanical design is compatible with standard gear selectors, including sequential shifting, and requires no additional modifications. The clutch’s blocking ring withstands high axial forces, preventing unwanted disengagement. Prototypes, tested in a standard five-speed gearbox, demonstrated up to 30 mm axial space savings compared to conventional synchronizers. The design supports effective serial production using powder metallurgy and has proven durability with a service life of 700,000 cycles.

References
[1] PILLOT, Christophe. The Rechargeable Battery Market and Main Trends 2020-2030. Lyon: Avicenne Energy, 2022.
[2] HOFMANN, Peter. Hybridfahrzeuge – Ein alternatives Antriebssystem für die Zukunft. Switzerland : Springer, 2014. Second edition. ISBN: 978-3-7091-1780-4
[3] NAUNHEIMER, Harald et al. Automotive Transmissions: Fundamentals, Selection, Design and Application. Berlin : Springer-Verlag, 2011. ISBN 978-3-642-16216-8.
[4] FISCHER, Robert et al. The Automotive Transmission Book. Switzerland: Springer International Publishing, 2015. ISBN 978-3-319-05262-5.
[5] MEHRGOU, Mehdi et al. NVH Aspects of Electric Drives-Integration of Electric Machine, Gearbox and Inverter. 2018. SAE Technical Paper 2018-01-1556. doi: 10.4271/2018-011556. ISSN 0148-7191.
[6] Wu,G.,Zhang, X.,& Dong, Z. (2015). Powertrain architectures of electrified vehicles: Review, classification and comparison. Journal of the Franklin Institute, 352(2), 425–448. doi: 10.1016/j.jfranklin.2014.04.018
[7] TŮMA Jiří. Vehicle Gearbox Noise and Vibration. New Delhi: John Wiley & Sons, Ltd., 2014. ISBN 978-1-118-35941-9.
[8] ČESKÉ VYSOKÉ UČENÍ TECHNICKÉ V PRAZE, FAKULTA STROJNÍ. Řadící spojka. Inventors: JASNÝ, M., G. ACHTENOVÁ and J. PAKOSTA. File No. MPT F 16 D 11/10. Patent No. 307443. 22. August 2018. Czech Office of Industrial Property. Patent.
[9] SCHECHISCHE TECHNISCHE UNIVERSITÄT IN PRAG, FAKULTÄT FÜR MASCHINENBAU. Schaltungskupplung. Inventors: JASNÝ, M., G. ACHTENOVÁ and J. PAKOSTA. IPC-Class F16D 11/00 (2006.01). File No. DE: 20 2018 103 633.5. 26. June 2018. Deutsches Patent- und Markenamt. Utility model.

Driving sustainability – Reducing the embedded emissions of copper in electric vehicles

Bruno De Wachter, Independent Advisor, International Copper Association

Since the publication of the EU Green Deal, e-mobility OEMs and Tier 1 suppliers in Europe have been actively seeking ways to evolve towards carbon neutrality. For such a journey to be successful, open  communication across the entire value chain is essential. This article develops the case for copper, a key raw material of the EV powertrain.

Copper in EVs – There is great potential to significantly reduce embedded GHG emissions associated with copper in the years to come.

Copper has the highest electrical conductivity of all non-precious metals, a quality put to good use in the stator windings of electric motors and induction motor rotors, as well as batteries, cabling and electrical connections. As OEMs and Tier 1 automotive industry suppliers develop their decarbonization plans, reducing copper’s embedded greenhouse gas (GHG) emissions is one of the challenges. A common approach to achieving this is by setting out a series of KPIs and milestones for their copper suppliers.

The good news is that there is certainly potential for reducing the carbon emissions from copper production to net-zero over the coming 30 years, and without the need for major technological breakthroughs. But for these conditions imposed by manufacturers in the automotive industry to be effective and actually help the copper industry speed up their decarbonization process, they have to be formulated in the right way, which requires some insight into the copper production process and material flows.

The copper production process and its emissions

A whole sequence of processing steps is required to produce high purity copper. The process of extracting primary copper from ores begins, of course, with mining, followed by concentration through a flotation process, and a first stage of refining in smelters using pyrometallurgical methods. The material is then subjected to a second stage of refining through electrolysis. An alternative route for low grade ore is the hydrometallurgical process, which separates the copper from the ore through leaching and then extracts it from the remaining solution through electrowinning.

Secondary copper is produced from scrap originating from manufacturing processes or end-of-life products. High purity scrap can be remelted directly with no need for refining, while less pure scrap requires additional processing. This can take place in dedicated secondary smelters, or the material can be added to the primary production process at various stages, depending on the scrap’s purity. This means that high-quality copper metal is often produced from a combination of primary and secondary sources.

According to an analysis by the International Copper Association (ICA), copper production currently leads to a total of 97 million tonnes of GHG emissions annually, or 0.2% of total global emissions. Of these emissions, approximately 70% are generated by mining, 23% originate from smelting and refining, and the remaining 7% come from upstream and downstream transport and end-of-life treatment of products.

A major component of the GHG emissions associated with primary copper comes from electricity, from fossil fuels used in mining transport and equipment, and from fuels used in smelting furnaces at various stages of the production process. The GHG emissions of secondary copper depend on the purity of the scrap, since this determines at what stage in the refining process it is added, but they are generally lower than those from primary copper. That said, using secondary copper can never be the sole and complete solution to decarbonization, as explained later. For this reason, reducing the impact of the primary production routes should receive major focus in the decarbonization process.

The pathway to net-zero

The decarbonization of the copper production process has already started, with numerous initiatives by individual companies involved in copper mining and refining. To step up the momentum, the ICA with its members developed a path forward to bring the carbon foot print of copper production as close as possible to net zero by 2050 (’Copper – The Pathway to Net Zero’). Made public in March 2023, the Pathway sets out a pragmatic approach to decarbonizing copper production, using existing technologies. It delineates which decarbonization options can be activated, by when, and with what impact. It also outlines some enabling conditions that should be in place to achieve this.

For scope 1 and scope 2 emissions, the Pathway identifies four major types of levers. The first is equipment electrification, to include the haulage trucks used in mining. An example of good practice is demonstrated by Boliden, a Swedish mining company which introduced electric trolley assistance in its haulage trucks in 2018, saving significant amounts of diesel fuel (Boliden, 2018). At the same time, underground mining machinery is being electrified at a rapid pace, coming with the additional benefit of saving the energy and cost of ventilation. The second lever is decarbonizing the electricity supply. This includes switching from standard to green electricity, alongside the option of installing wind and solar energy farms at copper production sites. A third lever is replacing fossil fuels with biofuel, biogas, or green hydrogen, particularly in smelting furnaces. A fine example of this is at German copper producer Aurubis, which has started using hydrogen instead of natural gas for the reduction process in its anode furnaces – an innovation set to reduce GHG emissions by around 5,000 tonnes each year (Aurubis, 2023). The fourth major lever encompasses various kinds of energy efficiency improvements at various stages of the production process. In a collective commitment, ICA members declared that they will be applying these and other measures to reduce their scope 1 and 2 emissions by 30 to 40% by 2030, 70 to 80% by 2040, and 85 to 95% by 2050.

A similar approach has been followed for scope 3 emissions, subject to the proviso that the results for this category depend on all the actors in the value chain collaborating. ICA members aim to reduce these emissions as far as possible by 2050, and will do what they can to unite every stakeholder behind this goal.

Recycling and decarbonization

Copper’s infinite recyclability is a major advantage. About 80 percent of copper is used in an unalloyed form, making the recycling process more straightforward. Even for copper that is alloyed or contains other materials, recycling can still be achieved without downgrading. Unwanted elements can be efficiently removed to recover the copper in its pure state, ready to be re-used in any kind of application. Because of its high degree of recyclability, copper already in use in its various applications is not regarded as lost, but can instead be legitimately considered part of the world’s copper reserve, often referred to as society’s „urban mine”.

Its high level of recyclability, combined with the fact that copper from secondary sources produces fewer GHG emissions than primary sourced copper, could lead to the simplistic conclusion that increasing the share of secondary material would be a good strategy for reducing embedded emissions. While this solution will work at individual plant level, it does not make sense on a European or world wide scale. Due to the long average lifetime of products using copper (typically 25 to 30 years) and strong growth in copper demand (practically doubling every 30 years), the availability of end-of-life material is far too limited to meet the demand for new material. Additionally, no process is 100% efficient, and there will always be losses associated with collecting, separating, and re-processing copper scrap.

Note that a distinction should be made between fabrication scrap, which originates from the production of end-use material out of semi-finished goods, and end-of-life scrap, which originates from end-of-life products.

Globally, scrap recycling rates from end-of-life products averaged around just 15% over the period from 2000 to 2020. Estimating future recycling rates is complicated by various uncertainties, but MineSpans by McKinsey expects the end-of-life recycling input rate to increase to 23 percent over the next 30 years.

Fabrication scrap contributed to about 16% of semi-finished goods production globally, a figure expected to remain stable. Bearing this in mind, any requirement set by raw material purchasers to increase the total recycled content of new copper above 35%-40% can only result in less recycled material being used elsewhere, leading to zero net reduction in GHG emissions at global level.

Moreover, the main levers for increasing recycling rates are in the collection and separation of end-of-life material, and consequently not in the hands of copper producing companies. Design engineers at every level of the automotive industry can play their role by favouring product designs that facilitate dismantling and separation at end-of-life (“design for recycling”). In some cases, collaborations between various stakeholders and the copper industry to capture and process the cleanest scrap and create a closed loop can set a good example. Recycling rates could also benefit from incentives for end-of-life collection, from staff upskilling for end-of-life management, and from improved separation techniques for treating multi metal scrap streams. Improved systems for car registration and waste stream reporting could avoid end-of-life vehicles being exported from the EU or going under the radar in other ways.

Collaboration across the value chain

All this considered, e-mobility OEMs and Tier 1 suppliers should not be over-concerned about the feasibility of reducing the embedded GHG emissions of copper conductors. The ICA and its members have developed a decarbonization pathway for the next 30 years based on existing technologies and that will bring the carbon footprint of copper production as close as possible to net zero by 2050. But to unlock its full potential, the pathway depends on stakeholder across the value chain communicating and collaborating with each other, upstream from copper production as well as downstream.

Purchase managers from the automotive industry can work with their copper suppliers to develop a roadmap to reduce embedded emissions and offer collaboration avenues to accelerate the process.

Raw material sourcing managers responsible for purchasing copper products should be aware of the limits of using recycled content as a means of reducing embedded GHG emissions. At the same time, they could consider developing closed loop business models for copper used in the automotive industry. Design engineers can play their role in this process by facilitating dismantling and separation at end-of-life.

With this level of collaboration across the entire value chain – stake holders communicating and interacting and achieving what is within their reach – there is great potential to significantly reduce embedded GHG emissions associated with copper in the years to come, while improving the collection and recovery rates of copper in end-of-life vehicles.

Intelligent bearing monitoring with LubeSecure from HCP Sense

Nico Kratz, Test Field Manager, HCP Sense GmbH
Ansgar Thilmann, Managing Director, HCP Sense GmbH

HCP Sense is an innovative start-up from Darmstadt that develops intelligent bearing monitoring systems for industrial applications. With a focus on predictive maintenance and condition monitoring, HCP Sense offers solutions to maximize operational efficiency, minimize downtime and extend the lifespan of machines.

The LubeSecure technology utilizes the fact that a bearing under full lubrication can be viewed as a capacitor in the electrotechnical sense in which the lubricating film acts as a dielectric. By measuring the electrical impedance, it is possible to differentiate between different lubrication states. This innovative approach makes it possible to react to inadequate lubrication at an early stage, before permanent metallic contact and the associated increased wear and tear occur. With that, LubeSecure technology doesn’t detect damages when they occur, as comparable condition monitoring technologies, but detects the underlying reasons for damages before they can actually form.

The following graphic shows the Stribeck curve from an electrotechnical perspective, illustrating the relationship between the specific lubricant film thickness and the electrical behavior.

Specific applications of LubeSecure technology

LubeSecure technology offers the following applications for rolling and plain bearings, among others:

1. Lubricant film monitoring:
Over 80% of bearing damage is due to lubrication problems in the bearing. HCP Sense’s impedance-based lubricant film monitoring enables early detection of a lack of lubricant or the use of a lubricant that is unsuitable for the application in question. In addition, natural and temperature-related lubricant ageing can be reliably identified.

Furthermore, in the development of the drivetrain of electrically powered vehicles for passenger cars and commercial vehicles, energy consumption can be reduced without jeopardizing durability. This is achieved because the use of LubeScure allows the lubrication to be ideally matched to the mechanical components and the framework conditions prevailing in reality.

2. Determination of the viscosity ratio κ:
The viscosity ratio κ is the measure of the quality of lubricant film formation in bearings. This makes it possible to determine in real time when the operating condition changes from mixed to liquid friction, for example, and whether the lubricating film is sufficiently formed. The additives contained in many lubricants are also taken into account. By using machine learning, HCP Sense can determine the viscosity ratio of a wide range of lubricants in real time, thus laying the foundation for optimized and low-wear machine operation. Our machine learning algorithms are trained with customer data and test data from our in-house testbenches, making sure that we use high quality data to further improve the predictions made by LubeSecure.

3. Identification of contamination:
The technology’s high measuring frequency ensures that even the smallest particles in the bearing can be identified at an early stage. Be it metallic debris from wear in the system or non- metallic particles from your process, LubeSecure detects changes in the lubricant condition almost immediately. This allows machines to be stopped in good time and maintenance measures to be initiated before major damage occurs.

By implementing LubeSecure technology, companies can not only plan their maintenance intervals more efficiently, but also optimize the energy consumption of their machines and increase overall operational safety.

The HCP Sense technology is currently being used successfully in numerous Gearbox test benches, field tests and from 2025 as a sensor installed as standard in new machines. Customers are already benefiting from the fact that they can prevent lubrication-related bearing damage, recognize machine failures at an early stage and plan maintenance more effectively. The areas of application are diverse and range from tunnelling machines to drivetrains and household appliances.

For more information:
www.hcp-sense.com
thilmann@hcp-sense.com

„In addition to reducing the risk of failure, the optimum operating condition identified by LubeSecure also contributes to significant energy and CO2 savings.”
Ansgar Thilmann, Founder & Managing Director, Commercial Director, HCP Sense GmbH

The first standard specification for EV fluids by TotalEnergies

Liang XUE, Emmanuel PINOT, Emmanuel MATRAY, TotalEnergies Lubricants Technology and Product Engineering Flavio SARTI, Richard VERNAY, TotalEnergies R&D

TotalEnergies Lubrifiants developed the first standardized specifications for Electric Drive System (EDS) fluids. This new performance standard is a first in the industry for hybrid and electric vehicles.

Pioneering electrical lubrication

In 2019, TotalEnergies Lubrifiants introduced Quartz, Rubia and Hi-Perf EV Fluids, the world’s first ranges of fluids specifically engineered for hybrid and electric vehicles, covering both light and heavy vehicles as well as two-wheelers. These fluids were designed to meet the specific requirements of hybrid and electric vehicles, as well as associated electrical, thermal, and frictional constraints.

TotalEnergies Lubrifiants EV Fluids were also designed to meet the needs of automobile manufacturers and support them in developing eicient driveline systems, while maintaining the vehicles in optimum operating conditions throughout their service life.

Today, TotalEnergies Lubrifiants is once again demonstrating its commitment to innovation in hybrid and electric vehicle lubrication by developing the first standardized specifications for Electric Drive System (EDS) fluids.

This development comes at a time when no standard exists for EV fluids, unlike conventional transmission oils. This standard has been drawn up to ensure that EV fluids meet strict criteria such as viscosity, oxidation, corrosion, durability and material compatibility, while optimizing the fuel eiciency and performance of electric motors and transmissions.

A comprehensive specification

TotalEnergies Lubrifiants has taken the lead in developing this specification tailored specifically for these fluids. Leveraging its expertise and cutting-edge testing resources, TotalEnergies has introduced this new performance standard, a first in the industry for hybrid and electric vehicles. This standard is designed to provide crucial support for automobile and parts manufacturers.

This very first specification has been achieved through a selection of test procedures. Based on TotalEnergies Lubrifiants’ extensive expertise in the field of fluids, this methodological development process firstly guarantees the good physicochemical properties of Quartz, Rubia and Hi-Perf EV Fluids, as well as their compatibility with diferent materials, in particular the new materials used in electrical applications, compared with conventional transmissions. Next, the tribological properties and durability of TotalEnergies Lubrifiants EV Fluids has been verified and confirmed at component level for gears and bearings. In addition, this process has included the creation of several test benches. First, a standardized bench was created to test the eiciency of the transmission at high speed in order to classify fluids according to their ability to improve battery life. A standardized bench was then developed for drive units to classify fluids according to their thermal capacity in electric motors. Finally, a durability methodology has been designed, based on road data and implemented on powertrain test beds, to speed up the vehicle validation process by reducing the time required.

The new specification is an industry first for electric vehicles. It is designed to ensure that TotalEnergies EV Fluids deliver outstanding performance when faced with the specific challenges of electric applications. It demonstrates once again TotalEnergies’ pioneering role in the transition era of vehicle electrification and its commitment to developing cutting-edge vehicle technologies, as well as its commitment to supporting vehicle manufacturers with innovative and tailored solutions and tools. With this new EV Fluids standard, TotalEnergies Lubrifiants continues to strengthen its position as a leading innovator in electric and hybrid vehicle lubrication.

Leading the way in e-fluid developments

As automakers work to decarbonise, most are opting for powertrain electrification, an option that is driving growth in dedicated hybrid and electric vehicle transmissions. However, these systems present new performance challenges that require dedicated fluids to ensure their complete protection. As leaders in driveline additive technology and e-fluid formulation, Infineum has invested in the development of step-out technology and innovative new test methods to ensure our e-fluids deliver the required performance in critical areas.

Andrew Wood, Driveline Fluids Technologist, Infineum UK Ltd
Scott Campbell, Hitesh Thaker, Masahiro Ishikawa, Driveline Fluids Technologists, Infineum USA

The pressure to decarbonise, coming from both regulators and con sumers, means the number of hybrid and battery electric cars on our roads is growing. Which in turn means the use of reduction gearboxes and dedicated hybrid transmission systems are also increasing. This expanding electrified vehicle parc needs bespoke e-fluids, that provide not only traditional transmission fluid properties but also meet new e-specific requirements.

Fig. 1 e-fluid requirements

It’s a careful balance. As well as meeting all of the requirements in Figure 1, fluids must be formulated to optimise transmission performance and protection. And, in today’s lower viscosity environment, this is even more vital, which means careful component selection is important when formulating fluids for these applications.

These new electrified vehicle performance challenges require dedicated e-fluid technology. As leaders in driveline additive technology and e-fluid formulation, Infineum has developed dedicated e-fluids, optimised for excellent field performance. To assess these new fluids, we’ve developed innovative new tests in some of the critical areas, designed to be closer to the real-world application than currently available industry test methods. Two recent examples are a high-speed aeration test (HSAT) and an energised copper test (ECT), which have given our technologists new and exciting insights into fluid performance.

Material compatibility testing

With motors now being placed into the transmission, a number of materials are being introduced that are significantly different from those used in conventional powertrain architectures. For example, the copper wire and connections are susceptible to corrosion, which can lead to electric current leakages or to a short circuit in the transmission. These potential issues mean many OEMs see copper compatibility as an important e-fluid design parameter.

With motors now being placed into the transmission, a number of materials are being introduced that are significantly different from those used in conventional powertrain architectures. For example, the copper wire and connections are susceptible to corrosion, which can lead to electric current leakages or to a short circuit in the transmission. These potential issues mean many OEMs see copper compatibility as an important e-fluid design parameter.

Infineum’s energised corrosion test (ECT) uses a single printed circuit board with copper grids, that can be used with a covering board to provide a capillary gap (Figure 2). Board spacing can be tuned with a spacer washer and various board designs have been used to investigate trace spacing impact.

Fig. 2 The oil immersed energised corrosion test (ECT) allows us to screen technology to ensure good copper compatibility.

Tuning trace and board spacing had a significant impact on fluid performance (Figure 3). These data highlight the critical importance of tuning test conditions and set-up to screen for real world performance.

Fig. 3 Impact of trace and board spacing

The novel video imaging system has delivered new insights into copper corrosion mechanisms (Figure 4).

Fig. 4 Deposit / dendrite growth between anode and cathode

This new rig is helping us to better understand some of the parameters impacting corrosion and the ways corrosion progresses. These insights will be helpful in developing advanced e-fluids capable of delivering better material compatibility performance.

New high speed aeration test

Infineum has also developed a high-speed aeration test (Figure 5), which more closely matches the conditions found in high-speed e-motors and gearboxes vs the standard ASTM test – addressing a gap in e-fluid performance.

While ASTM D892/D6082 use airflow to generate foam in the test fluid the foam may not be representative of aeration experienced in real world electric vehicle hardware, where e-motors and gears spin at >20,000 rpm – much faster than in conventional ICEs.

In electrified applications, high speed shear from gears and bearings can lead to increased aeration of the driveline lubricant. This is a challenge since it can cause cavitation. This leads to irregular fluid film and loss of hydraulic performance, resulting in wear.

Using the existing ASTM D892 and D6082 foaming test as a starting point, our objective was to mimic the impact of parts spinning at speeds of up to 27,000 rpm and to add in a high-speed shearing and churning effect to simulate the aeration caused by parts spinning at these very high speeds. Automation and video capture help to ensure heating and timing accuracy.

The newly developed High Speed Aeration Test (HSAT) has been used to assess the impact of fluid viscosity, viscosity modifier and anti-foam selection on aeration.

Following the successful development of this new test, Infineum is pursuing options for industry standardization of the HSAT.

Fig. 5 The Infineum HSAT test set up mimics the effect of parts spinning at extremely high speeds under shearing/churning

Conclusion

As leaders in driveline additive technology and e-fluid development, Infineum has invested in developing new test methods to provide insights into critical performance areas. The deeper understanding of materials compatibility and aeration is helping us to develop step-out dedicated e-fluids with the optimal performance balance designed to protect electrified transmission systems.

Our new test methods give us a fast and effective means to screen a wide number of formulations.

Following on from these laboratory tests, our advanced e-fluids are tested in real-world conditions. We have already completed almost three million kilometres of field trials across the globe – testing our extensive e-mobility product portfolio in a wide range of hybrid and electric vehicles.

Infineum technology is setting the e-fluids benchmark with next generation products to provide performance you can rely on.

About Infineum

Infineum is a specialty chemicals company with strong research and development capabilities focused on innovative chemistry that plays a crucial role in sustainability. They provide products essential for the electrification of mobility and work towards making internal combustion engines as clean as possible. Their expertise extends to generating sustainability advantages for numerous new markets globally. The company has a rich heritage supported by leading-edge research and development activities, having been innovators of additive products for nearly 80 years. These products are used in automotive, heavy-duty diesel, and marine engine oils, diesel fuels, and specialty applications such as transmission fluids and gas engine oils. Their smart solutions have become key components of today’s most demanding applications and advanced hardware systems. The organization operates worldwide production facilities with sales representation in more than 70 countries.