Standardization of laser marking for tracking gas pipes in transmission and distribution projects by destructive and nondestructive tests.

Rasooly, Meysam; Technical Inspection; Iran

Abbasian, F.; Islamic Azad University of Najafabad; Iran
Alavi, M.; Isfahan Province Gas Company; Iran
Mohseni Homagerani, E.; Isfahan Province Gas Company; Iran
Rasooly, M.; Isfahan University of Technology; Iran

ID: ECNDT-0429-2018
Download: PDF
Session: Process Control 2
Room: R2
Date: 2018-06-12
Time: 14:10 - 14:30

Gas pipelines need to be traced due to the sensitive usage and the number of involved mills. This research, implementation of laser engraving for marking API 5L pipes is standardized and run in deferent mills. Technical specification of method based on minimum requirements have been reviewed to obtain permanent marking without any effect on performance characteristics of pipes. Initial samples have been engraved to find the appropriate laser characteristics in practical condition. The next step was proposing test method and acceptance criteria of all destructive and nondestructive tests. Depth gaging, visual check for testing uniform engraving and suitable font and absence of sharp corners are some routine tests.

All circumferential welds in network shall be tested based on implementation codes; in this point of view in tracing pipes laser marking has its effect on radiography films that could be referred as a permanent document.
Validation of optimized items for engraving was analyzed to reach the deepest engraving in the shortest time. The results admitted the laser power is the most effective parameter.
Metallography, corrosion assessment, hardness, and tensile tests were performed as destructive routine tests. The results satisfied API 5L standard’s requirements. Consequently, the absence of heat-affected zone (HAZ) at the laser engraved region was observed.
Efficiency level, safety points, energy usage and economic aspects are considered to reach the best traceability in manufacturing and storage level, in coating process and also in the project site; therefore undesired or intentional pipe substitution in network installation of gas transmission and distribution pipeline could be checked as main result. In this point of view several engraving depths were assessed and probable damage mechanisms are evaluated by proposed DT and NDT for grade B, X42 and X52 for pipe sizes 4”, 6” and 8”.