DOI QR코드

DOI QR Code

The Effects of Welding Wires on the Weldabilities of API X-100 with Laser-Arc Hybrid Welidng

API X-100의 레이저-아크 하이브리드 용접성에 미치는 용접와이어의 영향

  • Received : 2014.10.22
  • Accepted : 2014.10.30
  • Published : 2014.10.31

Abstract

In this study, API-X100 steel pipes were welded with various kinds of welding wires in the laser-arc hybrid welding process. 10kW fiber laser source was combined to MIG arc welding process. API X-100 steel of base metal was of 16.9mm thickness, and butt welding applied. After welding, full penetration weld was acquired by 1-pass welding. A root porosity and the lack of fusion was observed in some welding conditions. By the mixing the melted wire, acicular ferrite, polygonal ferrite, pro-eutectoid, aligned side plate, and bainite structures were observed at the weld metal. From the observation of hybrid weld, unmixed zone had more Ni and Cr. The unmixed zone was a 1/3 area of the weld metal. As the mechanical test of the hybrid welding, tensile test and impact test applied. From the tensile test, all of the welding except SM70S was fractured at the base metal. The result of the impact test at -30 degree C led 60J~320J of the absorbed energy. The result of the low-absorbed energy might be from the coarse equiaxed structures of the weld metal.

Keywords

References

  1. Y.N.Ahn et al.: Laser arc hybrid welding for offshore pipeline construction, Proceedings of KWJS 2013, 110 (in Korean)
  2. Sang-Ho Uhm et al.: Behaviors of Microstructures and Properties in API X70 SAW Weld, Journal of KWS, 23-2 (2005), 66-74 (in Korean)
  3. Mok-Young Lee et al.: Technical Investigation on Nd:YAG Laser-GMA Hybrid Welding, Journal of KWS, 22-1 (2004), 26-31 (in Korean)
  4. Thomas O. Miesner et al.: Oil and Gas Pipeline, Penn- Well Corp. 2006, 357
  5. W.M.Steen et al.: Arc Augmented Laser Welding, Advances in Welding Processes Proceedings, 4th International Conference, Harrogate, U.K. May 9-11, 1978
  6. M.Y.Lee et al.: Laser-arc hybrid welding, J. RIST, 18-1(2004), 16-23
  7. EWI Project No. 49191CPQ: Fiber Laser-Based Hybrid Automated Pipe Girth Welding, April 30, 2008
  8. R.Miranda et al.: Characterization of fiber laser welds in X100 pipeline steel, Materials & Design, 30-7 (2009), 2701-2707 https://doi.org/10.1016/j.matdes.2008.09.042
  9. Z.Zhang et al.: Influence of Mn and Ni on the Microstructure and Toughness of C-Mn-Ni Weld metals, Welding Journal, 76-5(1997), 183S-190S
  10. C.B.Dallam et al.: Flux composition Dependence of Microstructure and Toughness of Submerged Arc HSLA Weldment, Welding Journal, 64(1985), 140S-151S
  11. G.M.Evans: The effect of Nickel on Microstructure and Properties of C-Mn all Weld Metal Deposits, Welding Research Abroad, 41(1991), 70-83