Wear of a polyurethane rubber used in dry gas pipeline as inspection gauges

• Published in: Journal of natural gas science and engineering Vol. 41; pp. 40 - 48
• Main Authors: Zhang, Hang, Sanchez, Carlos, Liu, Shuhai, Zhang, Shimin, Liang, Hong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2017
• Subjects: Dry friction; Gas pipeline; PIGs; Polyurethane rubber; Wear; PIGs; Polyurethane rubber; Gas pipeline; Wear; Dry friction
• ISSN: 1875-5100
• DOI: 10.1016/j.jngse.2017.02.035

Pipeline inspection gauges (PIGs) are essential for regular maintenance in natural gas exploration in cleaning and inspection. Their sealing discs, made of polyurethane rubber (UR), are often found to be worn quickly due to rubbing against steel surfaces. The damage in the UR sealing disc would cause a PIG stuck in operation (pigging). In this research, we investigate the frictional behavior and wear mechanisms of the UR sealing disc. Experimental study was carried out on UR samples against steel pipe materials using a pin-on-disc tribometer. The morphology and wear modes were studied using an optical microscope combined with finite element method (FEM). Results showed the completing mechanisms of abrasion, oxidation, and surface fatigue. The inter-correlation between these three modes and test conditions are discussed here. The understanding obtained in this research is beneficial for the improvement of pipeline design and operation. •The wear behavior of the UR sealing disc in dry pipe was investigated.•The completing wear modes of UR contain abrasion, oxidation, and surface fatigue.•The changing contacting makes the friction coefficients irregular and unpredictable.•Wear mode of UR evolves with the pass of sliding distance.•The different contact stress between the rubbing pairs affect the wear mode of UR.