GREVEN INSIGHTS LUBRICANTS: Sustainable Coolants
Metalworking fluids, often referred to as coolants or cutting fluids, play a crucial role in industrial manufacturing. Their primary functions are to cool both the tool and the workpiece and to reduce friction between the components, which in turn minimizes tool wear. While technical performance was the main focus in the past, today, sustainability and human compatibility are increasing in significance.
The requirements for modern coolants are diverse and sometimes conflicting. This leads to complex formulations with a multitude of individual components, which can result in composition challenges. The correct selection of base oil and additives is crucial, particularly for water-miscible coolants.
A key additive in water-miscible coolants is the emulsifier. It reduces the interfacial tension between the oil and water phases, enabling a stable distribution of oil droplets in water. This results in a stable oil-in-water emulsion, which is essential for the effectiveness of the coolant.
Testing ester base oil
Traditionally, hydrocarbons have been used as the base oil component, but the demand for ester base oils is steadily growing. For this reason, we wanted to explore the potential of our synthetic esters in coolant formulations. In collaboration with KAO Chemicals GmbH, a successful base formulation was developed in which a naphthenic base oil was replaced with an ester.
Various tests were conducted to evaluate performance, including the tapping torque test, corrosion behaviour on aluminium, the Krüss foam test and electrolyte scans. The results of the generated emulsions are comparable to those of petrochemical-based coolant emulsions used as a reference.
Using additives from KAO Chemicals GmbH and other manufacturers, certain esters can be easily processed into stable emulsions, including:
| LIGALUB 18 TMP A | unsaturated TMP ester of ISO VG 46 |
| LIGALUB 25 TMP | unsaturated, modified TMP ester of ISO VG 46 |
| LIGALUB 58 NPG | unsaturated NPG ester with a viscosity range of 23-29 mm²/s |
| LIGALUB 63 NPG | saturated NPG ester of ISO VG 46 |
These new formulations offer a sustainable and high-performance alternative to conventional coolants.
We would be pleased to present the results of our collaboration in detail and identify the additives used. For further information about our esters as a forward-looking solution for sustainable metalworking, please contact our Product Manager Nadine Flügel!
