Evaluation of a Coal Tar Epoxy Coating Performance for Pccp of the Great Man Made River Project Pipelines in Libya

Evaluation of a Coal tar Epoxy Coating Performance for PCCP of the Great Man-made River Project Pipe lines in Libya
Saad Arfan, Salah Elkoum
Great Man-Made River Authority (GMRA), Corrosion and Inspection Center, saad_qa@yahoo.com
selkoum@yahoo.com, P.O. Box 641 Libya, Benghazi, PH (00218) 91 3525389, Fax +218 61 2239590
Abstract
                       The barrier coating selected for the application to the external surfaces of the PCCP in aggressive ground conditions was coal tar epoxy.  This was selected on the basis of cost, ability to be applied to green mortar and hence minimal disruption to pipe production, has a track record, albeit limited, and has good dielectric properties.  However, it was appreciated that coal tar epoxy has poor ageing properties, rapidly becomes brittle and has poor crack bridging properties.  Due to this, cathodic protection is being provided to supplement the barrier coating.            This paper will present the results of the testing programme which was done to evaluate the performance of coal tar epoxy coating for PCCP pipes after fifteen years of service, samples were taken and tested.  The test result shows excellent performance of the coal tar epoxy coating.