EP Lubricants

[joro]

What is the difference between an extreme pressure (EP) lubricant and a lubricant that has extreme pressure additives?

If gear oil contains the EP additives is that enough to classify it as an EP lubricant?

I define each as follows:

EP (Extreme Pressure) lubricants -- lubricants that impart to rubbing surfaces the ability to carry appreciably greater loads than would be possible with ordinary lubricants without excessive wear or damage.

Extreme pressure (EP) additive -- lubricant additive that prevents sliding metal surfaces from seizing under conditions of extreme pressure. At the high local temperatures associated with metal-to-metal contact, an EP additive combines chemically with the metal to form a surface film that prevents the welding of opposing asperities, and the consequent scoring that is destructive to sliding surfaces under high loads. Reactive compounds of sulfur, chlorine, or phosphorus are used to form these inorganic films.

Any guidance would be greatly appreciated.

thanks
j.roth

 

[eyolova]

The EP lubricants usually or in most cases are produced by blending of ordinary base oils and EP additives.