Tecnologia em Metalurgia, Materiais e Mineração
Tecnologia em Metalurgia, Materiais e Mineração
Artigo Original

Investigating an API X65 steel pipe cladded with alloy 625

Rangel Knerek, Guilherme Vieira Braga Lemos, George Vander Voort, Diego Aires de Freitas, William Haupt, Renan Landell, Diogo Buzzatti

Downloads: 0
Views: 66


Pipes (rigid risers and flowlines) are employed to transport oil and gas from the wells to the platforms. In these pipes, the fluids can be very corrosive and, therefore, corrosion-resistant alloys (CRA) must be chosen. Alloy 625 is a well-known CRA with improved corrosion resistance. However, nickel-based alloys have high cost compared to that of the low alloy steels, thus pipes entirely made of CRA are economically unfeasible. Internal coating with a thin CRA layer is a less expensive and suitable alternative than the solid CRA. An internal coating by overlay manufacturing process can induce phase transformations at the interface. In this work, an alloy 625 cladding layer was deposited in an API X65 steel substrate with an automatic weld overlay system using gas tungsten arc welding (GTAW) process (often referred to as tungsten inert gas (TIG) hotwire). Thus, this study aims at evaluating an API X65 steel pipe cladded with alloy 625. The results show a suitable nickel-based alloy overlay deposited in an API X65 carbon steel substrate.


Welding; Clad pipes; GTAW; TIG hotwire; API X65 steel; Alloy 625.


1 Obeid O, Alfano G, Bahai H. Thermo-mechanical analysis of a single-pass weld overlay and girth welding in lined pipe. Journal of Materials Engineering and Performance. 2017;26:3861-3876.

2 Macdonald KA, Cheaitani M. Engineering critical assessment in the complex girth welds of clad and lines pipe materials. In: Proceedings of the 8th International Pipeline Conference; Calgary, Alberta, Canada; 2010. ASME. IPC2010-31627.

3 Moninea VI, Gonzaga RS, Farias FWC, Passos EKD, Payão JC Fo. Study of mechanical behavior and X-ray elastic constants of nickel alloy weld overlay. Materials Research. 2019;22(4):e20180719.

4 Smith L. Engineering with clad steel. 2nd ed. Canada: Nickel Institute; 2012.

5 Amudha A, Shashikala HD, Nagaraja HS. Corrosion protection of low-cost carbon steel with SS-309Mo and Inconel-625 bimetallic weld overlay. Materials Research Express. 2019;6(4):046523.

6 Kim JS, Park YI, Lee HW. Effects of heat input on the pitting resistance of inconel 625 welds by overlay welding. Metals and Materials International. 2015;21:350-355.

7 Lemos GVB, Hanke S, Dos Santos JF, Bergmann L, Reguly A, Strohaecker TR. Progress in friction stir welding of Ni alloys. Science and Technology of Welding and Joining. 2017;22(8):643-657.

8 Bunaziv I, Olden V, Akselsen OM. Metallurgical aspects in the welding of clad pipelines-A global outlook. Applied Sciences (Basel, Switzerland). 2019;9(15):3118.

9 Baiotto R, Knight-Gregson B, Nageswaran C, Clarke T. Coherence weighting applied to FMC/TFM data from austenitic CRA clad lined pipes. Journal of Nondestructive Evaluation. 2018;37:49.

10 Johnston C, Nageswaran C, London T. Investigations into the fatigue strength of CRA lined pipe. Offshore Technology Conference. Houston; Texas, USA. OTC; 2016.

11 Longlong G, Hualin Z, Shaohu L, Yueqin L, Xiaodong X, Chunyu F. Formation quality optimization and corrosion performance of Inconel 625 weld overlay using hot wire pulsed TIG. Rare Metal Materials and Engineering. 2016;45(9):2219-2226.

12 Olivares E, Díaz V. Estudo do processo TIG Hot-Wire com material de adição AISI-316L analisando o efeito do sopro magnético do arco sobre a diluição do cordão de solda. Soldagem e Inspeção. 2016;21(3):330-341.

13 Alvarães CP, Madalena FCA, Souza LFG, Jorge JCF, Araújo LS, Mendes MC. Performance of the INCONEL 625 alloy weld overlay obtained by FCAW process. Revista Matéria. 2019;24(1):1-12.

14 DNV GD. DNVGL-ST-F101: submarine pipeline systems. Noruega: DNV GD; 2017.

15 American Petroleum Institute. API 6A - Specification for Wellhead and Christmas Tree Equipment. Washington: API; 2005.

16 Song K, Wang Z, Hu S, Zhang S, Liang E. Welding current influences on Inconel 625/X65 cladding interface. Materials and Manufacturing Processes. 2018;33:770-777.

17 Rajkumar V, Arjunan TV, Kannan R. Metallurgical and mechanical investigations of Inconel 625 overlay welds produced by GMAW hardfacing process on AISI 347 pipes. Materials Research Express. 2019;6:076534.

18 Chong TVS, Kumar SB, Lai MO, Loh WL. Effects of elevated temperatures on the mechanical properties of nickelbased alloy clad pipelines girth welds. Engineering Fracture Mechanics. 2016;152:174-192.

19 Elango P, Balaguru S. Welding parameters for inconel 625 overlay on carbon steel using GMAW. Indian Journal of Science and Technology. 2015;8(31):1-5.

20 Lessa CRL, Landell RM, Bergmann L, Santos JF, Kwietniewski CEF, Reguly A, et al. Two-pass friction stir welding of cladded API X65. Procedia Manufacturing. 2020;47:1010-1015. http://dx.doi.org/10.1016/j.promfg.2020.04.311.

21     Rogalski G, Fydrych D, Łabanowski J. Underwater wet repair welding of API 5L X65M pipeline steel. Polish Maritime Research. 2017;24(Supplement 1):188-194.

22 Tahaei A, Vazquez FG, Merlin M. Metallurgical characterization of a weld bead coating applied by the PTA process on the D2 tool steel. Soldagem e Inspeção. 2016;21(2):209-219.

23 ASTM International. ASTM E8/E8M: Standard Test Methods for Tension Testing of Metallic Materials. West Conshohocken: ASTM International; 2013.

24 American Petroleum Institute. API 5L – Specification for Line Pipe. Washington: API; 2004.

Submetido em:

Aceito em:

605ddd4ba9539574ca64e8e2 tmm Articles
Links & Downloads

Tecnol. Metal. Mater. Min.

Share this page
Page Sections