AXEL News & Blog

What does “sustainable grease” actually mean for your application?

Sustainability requirements in industry are evolving rapidly, driven by both legislation and customer expectations. At the same time, Product Carbon Footprint (PCF) has become one of the most visible and widely used metrics for environmental impact.
But while PCF is an important tool, it does not tell the whole story. When used on its own, it can lead to decisions that look good on paper – but perform worse in practice.

This article aims to explain why sustainability in lubricating grease cannot be reduced to a single number, and how a more application-driven perspective leads to better environmental and business decisions.

Questions we often hear from customers and the industry:

• •    Which lubricating grease is most sustainable for my application?
• •    How should we weigh carbon footprint against other environmental aspects?
• •    Is it really better to switch to a grease with lower PCF, even if its service life is shorter?

Do these questions reflect the challenges your business faces as well? Read on to get a better understanding.

Background
Our Caliac thickener is made by a reaction process where both lithium hydroxide and either calcium hydroxide or calcium carbonate are allowed to react with fatty acids, usually 12-hydroxy-stearic acid. The ratio between the Li- and the Ca- components can be varied to achieve different properties from the thickener. The flexibility of the thickener system allows tailoring towards high load-carrying capacity and/or extreme water resistance. The Caliac thickener has properties in common with both the lithium thickener and the anhydrous calcium thickener. Typical treat rate for a NLGI 2 grease: 7 - 11 %

Background
Our Alassca thickener can be described as a combination of a lithium complex soap and sarcosylic calcium gel. The well-known lithium complex part forms the backbone of the thickener system and provides increased oil bleed and lubricity, and lowers total thickener content. This is important for successful use at lower temperatures. The attachment of the calcium gel to the lithium complex soap increases surface affinity and, thereby, the efficiency of these active components, providing resistance to extreme pressure, water, and corrosion. The thickener system is durable and contributes to surface separation, which means less reliance on the very high viscosity of the oil phase, in opposition to traditional aluminum complex and inorganic clay thickeners.

At the 2024 NLGI Annual Meeting, AXEL’s Prof. Johan Leckner presented a paper co-authored with Gabriel Calderon-Salmeron and Prof. Sergei Glavatskih of the Royal Institute of Technology in Stockholm. The paper illustrates how friction losses in electrical motor bearings can be accurately measured under a wide range of speed conditions.

Tribology International Publication compares lubrication performance under typical e-motor conditions.

Electric vehicle motors in e-drivetrains are equipped with grease-lubricated bearings operating at both low and high speeds with frequent speed changes. The grease-bearing system must secure a long lifespan and low frictional torque to improve efficiency and sustainability.

AXEL’s Lithium Complex Made with Love…for the Planet

The earlier success of our Calcium soap thickened products triggered ambitious plans at AXEL to provide biodegradable, non-toxic, highly renewable raw material containing Lithium Complex products for versatile applications.

In steel manufacturing the continuous caster provides quite a challenge for lubricant formulators. The bearings supporting the hot steel material needs to handle both high and shock load conditions, vibrations, high temperatures and/or water from cooling. The demands on the grease are therefore high too, so in order to provide sufficient lubrication the proper grease technology has to be selected.