A machine with moving parts only runs smoothly when the metal surfaces are separated by a lubricant film. Every surface has an intrinsic roughness.

When high pressures are exerted on two moving metal surfaces, e.g. in gear boxes, the asperities touch each other generating high temperatures. With poorly formulated lubricants, such contacts can lead to welding of asperities thereby ruining system performance.

Correctly formulated lubricants containing extreme pressure/antiwear additives (EP/AW additives), avoid such damage since these additives prevent welding even if asperities come briefly into contact.  

Ciba’s EP/AW additives for formulating a broad range of lubricants meeting State of the Art specifications include:
Ciba® IRGALUBE® 349; Ciba® IRGALUBE® 63
Ciba® IRGALUBE® TPPT; Ciba® IRGALUBE® 211; Ciba® IRGALUBE® 232