Erosion test proves performance of pipe-liner material
A recent erosion test project for a leading pipeline manufacturer has used an innovative accelerated test approach to deliver significant time and cost savings.
“The flexibility and performance of our erosive flow test facility allowed us to propose a test that was significantly faster and cheaper than an equivalent field test,” says Section Leader, Zak Latif. “We were also able to provide Computational Fluid Dynamics (CFD) analysis to inform aspects of the test, giving our client added peace of mind.”
The tests were carried out on a polymer lining that was designed to be used in riser systems to prevent corrosion from occurring. An oil and gas operator wanted to assess the performance of these polymer liners, however they were concerned that erosion would damage the liners over time. The operator therefore wanted the liner manufacturer to prove that the polymer did not erode faster than typical carbon steel. TUV SUD NEL was commissioned by the manufacturer to assess this aspect of the liner’s performance.
Zak and his team used a testing method using coupons (solid cylindrical pieces of carbon steel and the polymer). These coupons were inserted into TUV SUD NEL’s erosive flow loop, using a high content of sand in the flow. The sand content used was far greater than the concentration seen in operational conditions. This allowed the test to be completed more quickly than a comparable test at field conditions.
“Before the flow tests began the dimensions of each coupon was measured,” Zak explains. “The test was then run continuously for 144 hours at three flow velocities. At 24-hour intervals, all the coupons were removed and inspected. Photographs of the coupons along with their mass measurements were taken at each interval. After completion of the test, all coupons were removed and their final dimensions measured.”
Computational Fluid Dynamics (CFD) analysis was used to determine the velocities required to run the test initially. The results from the erosion testing were then used to validate the CFD model, which the client can now use for other requirements.
“Using the measured mass and dimensional results, the carbon steel coupons had a greater material loss due to erosion in comparison to the polymer,” Zak reports. “Overall, we were able to demonstrate that the polymer performed better than carbon steel.”