Abstract
The aim of this work was to investigate the corrosion rate of welded carbon steel pipe (ASTM (American Society for Testing and Materials) A106 Grade B) by GTAW under the currents of 60, 70, and 80 A. All welded pipes satisfied weld procedure specifications and were verified by a procedure qualification record. The property of used materials was in agreement with the ASME standard: section IX. The welded pipe was used for schematic model corrosion measurements applied in 3.5 wt % NaCl at various flow rates and analyzed by using the electrochemical technique with Tafel’s equation. The results showed the correlation between the flow rate and the corrosion rate of the pipe; the greater the flow rate, the higher corrosion rate. Moreover, the welded pipe from the welding current of 70 A exhibited higher tensile strength and corrosion resistance than those from currents of 60 and 80 A. It indicated that the welding current of 70 A produced optimum heat for the welding of A106 pipe grade B. In addition, the microstructure of the welded pipe was observed by SEM. The phase transformation and crystallite size were analyzed by XRD and Sherrer’s equation. The results suggested that the welding current could change the microstructure and phase of the welded pipe causing change in the corrosion rate.
Highlights
Piping systems play a critical role in the transportation of chemicals both liquid and gas from one location to another
The study of corrosion on carbon steel ASTM S/A106 grade B pipe welded by the gas tungsten arc welding (GTAW) at different of welding currents of 60, 70 and 80 A was investigated with various flow rates of 3.5 wt % NaCl electrolytes (15, 20 and 25 L/min)
The results of this could be summarized as follows: (a) the minimum corrosion rate of the piping specimen was 0.242 mmpy, when the welding current was maintained at 70 A and a flow rate of 3.5 wt % NaCl controlled at 15 L/min; (b) the maximum corrosion rate of welded pipe specimens was
Summary
Piping systems play a critical role in the transportation of chemicals both liquid and gas from one location to another. An A106 from American society for testing and materials standard (ASTM). Which covered in American society of mechanical engineers standard (ASME) of S/A 106 is a carbon steel pipe with excellent mechanical properties and thermal resistance. The welding method can produce piping for fluid systems which can support extreme conditions such as highly concentrated chemicals and high pressure steam. The heat transfer of the welding process has the potential to change the microstructure of the piping materials. The effects on the microstructure can be varied depending on the locality which is divided into three zones: the base zone, the heat-affected zone (HAZ), and the fusion zone
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
