Experimental study on the probe dynamic behaviour of feeler pigs in detecting internal corrosion in oil and gas pipelines

Leakages are the major cause of in-service natural gas and oil pipeline accidents, and many factors, such as corrosion, can lead to leakages. The feeler pig is one of the most typical contact-testing tools in oil and gas pipelines. In this paper, the probe dynamic behaviour of the feeler pig in detecting internal corrosion has been investigated using a handmade inspecting system. The dynamic characteristics of the probe are different in the uphill section and the downhill section, and the trajectory of the probe is asymmetric. A bouncing phenomenon was found in the outlet region of the corrosion. The experimental results indicated that both the speed and the spring pre-tightening elastic force are closely related to the inspection precision. The research in this paper provides guidance for studying the inspection precision of the feeler pig. (C) 2015 Elsevier B.V. All rights reserved.