The Permagraph process was first developed in response to a demand from the motor industry for a means of lubricating inaccessible bearings operating at extreme temperature (300°C plus) in kilns and stoving ovens.

 In the Permagraph process, a combination of high purity synthetic graphite and molybdenum disulphide is applied to the metal surface in such a way that it becomes an integral part of the surface and can only be removed by abrasion.

 The resulting dimensional change is negligible (in the order of 10 microns) but bearings required to operate at temperatures above 200°C should be of a C5 fit to allow for distortion due to stress relieving.

 Permagraphed bearings proved so successful that the process was extended to conveyor and power transmission chains operating at high temperatures and in abrasive or corrosive environments.  Permagraph   was also found to show high resistance to humidity at ambient temperatures.  This property was improved by applying a form of food-safe silicone following the graphite/molysulphide treatment.

 In addition to protecting against corrosion, the silicone prevents the adhesion of lint and waste products, and so is of particular interest to the food and textile industries.