Changes in machinery & equipment are impacting the performance requirements of grease, including the increasing demand for grease to perform at higher temperatures and under higher loads. While base oil and thickener selection can impact temperature performance significantly, there are also additive solutions that help meet the stringent needs of high temperature grease. Afton Chemical has a portfolio of additive solutions that impart heat and oxidation resistance to grease formulations.
How Do High Temperatures Affect Grease?
Temperature can drastically change the performance of a lubricant. High temperatures will cause oil to thin, making the oil more prone to leakage and can lead to equipment wear and damage. Elevated temperatures also accelerate oxidation, corrosion and decomposition and make oil more volatile. Grease is particularly affected by thermal stress. High temperatures can cause grease to separate quickly which can lead to oil drainage and grease dry-out. It’s critical that grease formulators consider and test for temperature performance when formulating.
Afton HiTEC® Additive Solutions
Antioxidant Technology
HiTEC® 55562 is an antioxidant that provides a performance boost in high temperature grease applications by imparting oxidation resistance and protecting the structural stability of grease under thermal stress. The graph below demonstrates the synergistic impact of using HiTEC® 55562 in combination with one of Afton’s multifunctional additive packages, HiTEC® 552. When used together, HiTEC® 55562 extended the high temp wheel bearing life by 3X.
Boronated Dispersants
Afton’s boronated succinimide dispersant technologies raise the dropping point of grease. Dropping point is the temperature at which a grease passes from a semi-solid state to a liquid state, and is used as an indicator of the heat resistance of a grease. Dropping point enhancers can be used in place of complexed grease soaps. When compared with complex grease, dropping point enhancers offer shorter production cycles, lower production costs, improved low temperature performance, and provide similar heat resistance.
Afton’s HiTEC® 637 and HiTEC® 648 boronated dropping point enhancers provide the following performance benefits to grease:
Raise the dropping point of grease formulations
Improve the structural stability under thermal stress
Can reduce the soap content
Provide additional corrosion, wear and extreme pressure performance
