Evaluation of Material Selection for Pipelines in Walnut Shell Filter Skid in an Oilfield

In order to solve the problem of serious corrosion and perforation of the pipeline in the walnut shell filter skid in an oilfield in the Middle East, four kinds of pipes, 316L stainless steel, 3Cr low alloy steel, antibacterial steel and polyethylene of temperature resistance (PE-RT II), were selected through literature research, and the material selection was further evaluated by compatibility, construction feasibility and economy. The results show that there was no dissolution, bubble, cracking and deformation on the surface of PE-RT II pipe after compatibility evaluation test. According to the extrapolation curve of hydrostatic strength, the service period of PE-RT II pipe under corresponding working conditions should be more than 20 a. The surface of 316L stainless steel, 3Cr low alloy steel and antibacterial steel showed uniform corrosion morphology, among which 316L stainless steel was slightly corroded, 3Cr low alloy steel and antibacterial steel were moderately corroded, and the service cycle of the three pipes under the corresponding working conditions should be more than 25 a. The PE-RT II pipe could be welded by hot melt welding and electrofusion welding, and the 316L stainless steel, 3Cr low alloy steel and antibacterial steel could be welded. All four pipes could meet the installation and construction requirements in the walnut shell filter skid. PE-RT II pipe was the most economical. In summary, PE-RT II pipe was preferred.