Erosion Behaviour of API X100 Pipeline Steel at Various Impact Angles and Particle Speeds

• Main Authors: Paul C. Okonkwo, Rana Abdul Shakoor, Moustafa M. Zagho, Adel Mohamed Amer Mohamed
• Format: Article
• Language: English
• Published: MDPI AG 2016-09-01
• Series: Metals
• Subjects: API X100 steel; dry erosion; alumina particles; impact angle; particle velocity
• Online Access: http://www.mdpi.com/2075-4701/6/10/232

Erosion is the gradual removal of material due to solid particle impingement and results in a failure of pipeline materials. In this study, a series of erosion tests were carried out to investigate the influence of particle speed and impact angle on the erosion mechanism of API X100 pipeline steel. A dry erosion machine was used as the test equipment, while the particle speed ranged from 20 to 80 m/s and impact angles of 30° and 90° were used as test parameters. The eroded API X100 steel surface was characterized using scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The weight loss and erosion rate were also investigated. The results showed that at a 90° impact angle, a ploughing mechanism was occurring on the tested specimens, while material removal through low-angle cutting was the dominant mechanism at lower impact angles. Embedment of alumina particles on the target steel surface, micro-cutting, and low-angle cutting were observed at low impact angles. Therefore, the scratches, cuttings, and severe ploughings observed on some failed oil and gas pipelines could be attributed to the erosion mechanism.