Tracking and erosion resistance of polymeric materials in oxygen deficient conditions

This paper describes two alternate procedures for evaluating the arc tracking and erosion resistance of polymeric materials used for insulation in electrically heated high-pressure pipes by the oil industry. The materials are subjected to electrical stress in a high-pressure gaseous medium that can have little or no oxygen, and conductive contaminants such as seawater. Presently, there is no procedure for evaluating the electrical tracking performance of materials under these conditions. A series of laboratory tests were performed using the ASTM D 2303 inclined plane (IP) testing arrangement under ambient as well as high-pressure conditions produced by nitrogen and methane. The results indicate that the tracking and erosion resistance of materials obtained under ambient conditions can be significantly different from those obtained in an oxygen deficient high-pressure media. Factors contributing to this difference are listed and analyzed.