Sulphur-containing additives are used in lubricating oils, hydraulic fluids, metalworking fluids and greases to provide extreme pressure (EP) and anti-wear (AW) properties. Their activity depends largely on the sulphur content and the type of sulphur compound. High sulphur additives are generally more effective EP agents than low sulphur additives. Moreover, there are two types of sulphur compounds: active and inactive sulphur. The main difference is that active sulphur reacts with the surface at much lower temperatures, whereas inactive compounds only react at much higher temperatures. Although additives with active sulphur have the advantage
of higher reactivity and can therefore offer better protection, especially at low temperatures, they are also slightly corrosive, in particular for yellow metals (brass, bronze, etc.). This is why in some cases the use of passivators is necessary.
The most common sulphur compounds are the following:
- Sulphur-containing olefins
- Sulphur esters
LUMAR has a wide range of sulphur additives to improve lubricant efficiency.
Contact us to find out which products best meet your needs.