Internal and external pipeline erosion due to suspended particulate matter, wax and sand content, and geoseismic motion can rapidly reduce pipeline wall thicknesses to critically low values. Due to low shrinkage rates on curing, epoxy polymer coatings are well suited for slowing the rate at which pipe wall thickness is lost. The abrasion resistance of an epoxy coating is a function of the hardness of the coating, the abrasive particle velocity, angle of impact, and particle size. This paper describes the authors’ attempts to estimate longevity of certain Bisphenol-A based epoxy coatings against particulate abrasion.
Details are presented for the abrasion resistance testing of four different commercial epoxy coatings. Experimental methodology is detailed consisting of two different methods of accelerated erosion testing: water-jet droplet erosion and fixed frequency mechanical abrasion. The methods are used to calculate abrasion endurance lifetime for a variety of pipeline installation environments.
Test samples are exposed to abrasive wear for a given period of time and material loss is measured. Loaded and unloaded abrasion testing is used to represent forces proportional to buried and non-buried piping. Erosion volume and time to the specified erosion depth are compared with control data on uncoated carbon steel substrates. This accelerated erosion data is transposed to reflect in-situ life expectancies.