Effects of welding wire composition and welding process on the weld metal toughness of submerged arc welded pipeline steel

2009 ◽  
Vol 16 (1) ◽  
pp. 65-70 ◽  
Author(s):  
D REN
Keyword(s):  
Weld Metal ◽  
Pipeline Steel ◽  
Welding Process ◽  
Welding Wire ◽  
Submerged Arc

Recommendations for Submerged Arc Spiral Welding With Optimized CTOD Properties

2018 ◽  
Author(s):  
Martin Liebeherr ◽  
Özlem E. Güngör ◽  
Nuria Sanchez ◽  
Hervé Luccioni ◽  
Nenad Ilic
Keyword(s):  
Weld Metal ◽  
Base Material ◽  
Welding Process ◽  
Experimental Program ◽  
Welding Parameters ◽  
Pipe Production ◽  
Filler Wire ◽  
Crack Tip Opening Displacement ◽  
Wide Range ◽  
Submerged Arc

Many pipe mills may not be familiar with a Crack Tip Opening Displacement (CTOD) requirement on the pipe seam weld, nor will they find easily relevant information in open literature. Influencing — and certainly not independent — factors are: welding parameters, base material and consumable selection. Out of these, the welding parameters such as heat input and cooling rate cannot be varied over a wide range during the pipe production, which means that the leverage is rather limited at the given welding process. The properties of the heat affected zone will be mainly affected by the base material, while the properties of the weld metal will be affected by both, base material and filler wire selection. In particular with respect to the weld metal properties it will be difficult to obtain general quantitative information. For example, a welding consumable supplier will readily provide the properties of the filler wires but would be unable to predict the changes caused by the dilution from any base material in the weld pool and specific welding procedures that may have been used. To support the pipe mills in the selection of the consumables for submerged arc welding, an experimental program was launched with the aim to provide recommendations on how to optimize CTOD toughness of the spiral weld seam. For this, a large number of welds were produced on 20 mm thick X70 coil samples, with eight different filler wire combinations, using a 2-wire (tandem) set-up for both the inside and outside weld. Welding parameters were kept constant. The welding program was applied to two different X70 steels to determine a potential influence of the micro-alloying elements, particularly Nb. The results show clearly that a careful consumable selection is required for obtaining acceptable CTOD toughness in the weld metal. Ni-Mo and Ti-B additions to the weld metal are found to be beneficial with both steel concepts. Mo addition alone both to the ID and OD welds was clearly not a suitable selection.

The Influence of Diffusible Hydrogen in Weld Metal and Moisture Content Levels in Flux Related With Weld Metal Mechanical Properties in Submerged Arc Welding Process for Line Pipe Manufacturing

2015 ◽  
Author(s):  
Gautam Chauhan ◽  
Piyush Thakor ◽  
Satyanarayana Samavedam ◽  
Ramakrishnan Mannarsamy ◽  
Ashif Sheikh ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Moisture Content ◽  
Weld Metal ◽  
Hydrogen Content ◽  
Welding Process ◽  
Diffusible Hydrogen ◽  
Line Pipe ◽  
Arc Welding Process ◽  
Submerged Arc ◽  
Pipe Manufacturing

The mechanical properties of welding material is correlative with the diffusible hydrogen content in weld metal and level of moisture content in flux. Minitab16program to predict mechanical properties correlated to diffusible hydrogen content in weld metal and level of moisture content in flux, such as yield strength, tensile strength, elongation and average Charpy impact toughness of welding material is established by using submerged arc welding process in line pipe manufacturing. The present paper aims to experiment and investigate the line pipe SAW Flux used for offshore/onshore applications. Flux moisture content has been studied under Karl Fischer Coulometer method. Subsequently, flux was then used to make weld to analysis for ‘diffusible hydrogen content in weld metal’ through mercury displacement method. This detailed study envisages and explains the correlations between the mechanical properties and micro structures of weldments. Evaluating the variance of moisture level in flux and diffusible hydrogen content in weld metal proves the advantage of restricting the moisture content along with good practices to accomplish better weld quality.

TMF Influence on Weld Structure at the Welding of 12X18H9T

2018 ◽  
Vol 927 ◽  
pp. 1-5 ◽  
Author(s):  
Alexander D. Razmyshlyaev ◽  
Marina V. Ahieieva ◽  
Elena V. Lavrova
Keyword(s):  
Magnetic Field ◽  
Weld Metal ◽  
Arc Welding ◽  
Welding Process ◽  
Metal Structure ◽  
Transverse Magnetic ◽  
Submerged Arc Welding ◽  
Structural Components ◽  
Weld Structure ◽  
Submerged Arc

The transverse magnetic field (TMF) use allows to obtain follow effects: increasing the electrode melting coefficient, reducing the base metal penetration depth and grinding the weld metal structural components. The paper analyzed the existing literature data about the TMF influence on the refinement of the weld metal structure. It is experimentally shown that the alternating TMF influence of 6 Hz frequency reduces the grain size of weld metal is almost twice in comparison with the welding process without the TMF influence at submerged arc welding of plates of austenitic steel type 12X18H9T (X10CrNiTi18-9). The average grains size is 7-6 index, when welding without the TMF influence and the average grains size of the weld metal corresponds to 8 index, with separate inclusions of grains with 7 index when welding with the TMF influence. This is should increase the yield strength value of the weld metal in accordance with the data of Hall – Petch.

Some Feasibility Studies for Recycling of Steel Slag as a Useful Flux for Submerged Arc Welding

2020 ◽  
Vol 19 (02) ◽  
pp. 277-289
Author(s):  
Sumit Saini ◽  
Kulwant Singh
Keyword(s):  
Weld Metal ◽  
Arc Welding ◽  
Steel Slag ◽  
Welding Process ◽  
Feasibility Studies ◽  
Submerged Arc Welding ◽  
Bead Geometry ◽  
Weld Bead Geometry ◽  
Arc Welding Process ◽  
Submerged Arc

Protection of environment from industrialization and urbanization waste is the prime duty of engineers and researchers. Elimination of industrial waste completely is not possible because it is generally a byproduct of the process. It can be minimized by recycling or reusing. In this research, waste slag generated by steel plant is recycled as a useful flux for submerged arc welding. It is found that recycled slag is capable of producing acceptable weld bead geometry. The penetration achieved using recycled slag is 7.897[Formula: see text]mm, which is more than the penetration obtained using fresh flux, i.e. 6.027[Formula: see text]mm. The reinforcement produced by recycled slag is 2.632[Formula: see text]mm, which is close to the reinforcement obtained using fresh flux. It is further observed that chemistry of weld metal deposited using recycled slag is also at par with that of weld metal produced using fresh original flux. The amount of carbon present in weld metal produced by recycled slag is 0.15%, which is comparable to the percentage of carbon present in weld metal produced using fresh flux. The microstructure and microhardness obtained using recycled slag are also comparable with the microstructure and microhardness obtained using fresh flux. This research established the feasibility of recycling slag as a flux required for submerged arc welding process.

Development of Welding Procedures for X90-Grade Seamless Pipes for Riser Applications

2012 ◽  
Author(s):  
Hiroyuki Nagayama ◽  
Masahiko Hamada ◽  
Mark F. Mruczek ◽  
Mark Vickers ◽  
Nobuyuki Hisamune ◽  
...  
Keyword(s):  
Weld Metal ◽  
Arc Welding ◽  
Mechanical Test ◽  
Welding Process ◽  
High Strength ◽  
Submerged Arc Welding ◽  
Welding Parameters ◽  
Flux Cored Arc Welding ◽  
Welding Procedure ◽  
Submerged Arc

Ultra-high strength seamless pipes of X90 and X100 grades have been developed for deepwater or ultra-deepwater applications. Girth welding procedure specifications (WPSs) should be developed for the ultra-high strength pipes. However, there is little information for double jointing welding procedure by using submerged arc welding process for high strength line pipes. This paper describes mechanical test results of submerged arc welding (SAW) and gas shielded flux cored arc welding (GSFCAW) trials with various welding consumables procured from commercial markets. Welds were then made with typical welding parameters for riser productions using high strength X90 seamless pipes. The submerged arc weld metal strength could increase by increasing alloy elements in weld metal. The weld metal with CE (IIW) value of 0.74 mass% achieved fully overmatching for the X90 pipe. The weld metal yield strength (0.2% offset) was 694 MPa, and the ultimate tensile strength was 833 MPa. It was also confirmed that the reduction of boron in weld metal can improve low temperature toughness of high strength weld metal. Furthermore, it was confirmed that the HAZ has excellent mechanical properties and toughness for riser applications. In this study GSFCAW procedures were also developed. GSFCAW can be used for joining pipe and connector material for riser production welding. The weld metal with a CE (IIW) value of 0.54 mass% could meet the required strength level for X90-grade pipe as specified in ISO 3183. Cross weld tensile testing showed that fractures were achieved in the base metal. Good Charpy impact properties in weld metal and HAZ were also confirmed.

scholarly journals The FN Process-A New Submerged-Arc Welding Process to Improve Toughness of Weld Metal (Report 1)

1964 ◽  
Vol 33 (1) ◽  
pp. 38-54 ◽  
Author(s):  
Tomomichi Hotta ◽  
Toyoaki Bada ◽  
Norio Tanaka ◽  
Izumi Morimoto ◽  
Hiroshi Nakayama
Keyword(s):  
Weld Metal ◽  
Arc Welding ◽  
Welding Process ◽  
Submerged Arc Welding ◽  
Arc Welding Process ◽  
Submerged Arc

Modeling of Heat Transfer in Pipeline Steel Joint Performed by Submerged Double-Arc Welding Procedure

2013 ◽  
Vol 814 ◽  
pp. 33-40 ◽  
Author(s):  
Dan Catalin Birsan ◽  
Elena Scutelnicu ◽  
Daniel Visan
Keyword(s):  
Heat Transfer ◽  
Arc Welding ◽  
Welded Joint ◽  
Pipeline Steel ◽  
Welding Process ◽  
Temperature Fields ◽  
Welding Procedure ◽  
Thermal Sources ◽  
Submerged Arc ◽  
Process Productivity

Submerged arc welding is the most applicable and productive procedure when thick sections have to be welded. Nevertheless, the manufacturers of pressure vessels, pipelines, ships and offshore structures keep on looking for new and modern design solutions of equipments and technologies which should lead to increase of welding process productivity. For instance, the longitudinal welds of pipelines are, mostly, performed by submerged arc welding procedure with multiple arcs and/or multi-wires, such as twin, tandem or twin-tandem, in order to increase the process productivity. However, achievement of optimal mechanical properties of the welded joint should remain the most important quality criteria. It is well known that dependence of the mechanical and metallurgical changes on heat transfer plays a major role in obtaining of safe welded structures and preserving of their structural integrity. That is why the investigation of heat transfer induced by the welding process is required. Furthermore, setting of distance between thermal sources and its influence on the overlapping phenomenon of temperature fields should be explored when submerged double-arc welding procedure is applied. Three dimensional finite element model of butt welded joint - used for simulation of heat transfer in pipeline steel joint performed by submerged double-arc welding process - is developed and described in this paper. Numerical results and a comparative analysis related to the temperature distribution, thermal history, and temperature variation in cross section of the welded joint at different time steps are discussed. Finally, important conclusions regarding the influence of distance between thermal sources on thermal effects and temperature fields overlapping are drawn.

A High Notch Toughness Agglomerated Flux for Submerged Arc Welding of Pipeline Steel

2006 ◽  
Vol 306-308 ◽  
pp. 405-410 ◽  
Author(s):  
De Liang Ren ◽  
Bo Liao ◽  
Changling Xu ◽  
Lianhai Hu ◽  
Fu Ren Xiao
Keyword(s):  
Low Temperature ◽  
Weld Metal ◽  
Arc Welding ◽  
High Speed ◽  
Uniform Design ◽  
Welding Process ◽  
Submerged Arc Welding ◽  
Notch Toughness ◽  
Technical Specifications ◽  
Submerged Arc

By using the mathematical uniform design, a new agglomerated flux for high speed and multi-arc submerged arc welding (SAW) has been developed in this paper, which performs excellently in welding process, and the effects of flux composition on the welding characteristics is analyzed as well. The mechanical tests show that the weld metal obtained in SAW with this flux exhibits high toughness at low temperature, and the other mechanical properties of the weld metal also satisfy the technical specifications for the West to East Pipeline Project in China. The microstructures of the weld metal are also examined. Both optical and TEM microphotoes demonstrate that the weld consists mainly of small-sized and uniformly distributed acicular ferrite. These microstructures can effectively prevent the initiation and propagation of micro cracks, resulting in high notch toughness of the weld metal at low temperature.

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