The Open Petroleum Engineering Journal

2016, 9 : 1-9
Published online 2016 February 09. DOI: 10.2174/1874834101609010001
Publisher ID: TOPEJ-9-1

RESEARCH ARTICLE
 Early Inspection of Weld Seams on Gas Pipelines Based on Metal Magnetic

Kexi Liao , Lijia Long, * and Huaixin Zhang
Southwest Petroleum University, Chengdu 610500, China

* Address correspondence to this author at the Southwest Petroleum University, Chengdu 610500, China; Tel: 861582810818686; E-mail: ; 15828108186@163.com

ABSTRACT

In order to investigate the magnetic abnormality influenced by stress in weld seams, experiments on three types of weld seams were carried out and a stress concentration detection instrument - metal magnetic memory (MMM) tester was used. MMM tests on gas pipelines in Puguang initial station in China were conducted and compared MMM wave diagram and mathematical analysis of MMM data and the quantitative MMM characteristics of T weld, straight weld and girth weld. The experiment results showed that different weld seams have different MMM characteristics, types of defects can be identified based on magnetic anomaly signal waveform characteristics and quantitative MMM features which evaluate the pipeline defects quantitatively.

Keywords:

Metal magnetic memory, stress concentration, weld seam.