Submerged Arc Welding Method Research Articles

Tozaltı Ve Gazaltı Kaynak Yöntemleri İle Birleştirilen Gemi İnşa Çeliğinin Kaynak Bölgesinin Mekanik Özelliklerinin İncelenmesi

Merchant ships are generally built by joining steels with various welding methods. When the welding methods used in shipyards are examined, it is seen that gas metal arc welding (GMAW), submerged arc welding (SAW), covered electrode arc welding and tungsten inert gas (TIG) welding come to the fore. In the assembly of ship hull sheets, GMAW and SAW are generally preferred. In this sense, it is extremely important to characterize the mechanical properties of the weld zone after welding of the shipbuilding steel joined by these two welding methods. When the studies examined, although there are few studies on the joining with GMAW and SAW of shipbuilding steels, no study has been found on the comparative examination of these two welding methods. In this context, within the scope of the study, 3701 shipbuilding steel, which is used extensively in shipbuilding, was joined with SAW and GMAW methods and the hardness, tensile, impact and bending properties of the welding zone were examined comparatively. In consequence of the tests, it was determined that higher mechanical properties were obtained than the base metal in both welding methods. Also, it was found that the welding zone of the shipbuilding steel joint by the SAW method had relatively better mechanical qualities.

Analysis of the process of qualifying the welding technology of S355JR structural steel using the submerged arc welding method

This paper presents the issue of welding technology qualification using the example of structural steel S355JR with a plate thickness of 25 mm and 100 mm, bevelling V. The main objective of this work was to attempt to perform a full qualification of the submerged arc welding process in accordance with the requirements of PN EN ISO 15614. Particular attention was paid to the issue of the qualification of welding technology. The samples were subjected to non-destructive testing, i.e. visual and penetrant testing, as well as ultrasonic testing and heat treatment. This was followed by destructive testing, including macroscopic testing and hardness testing. According to the proposed procedure for the recognition of submerged arc welding technology, once the necessary tests had been carried out and the protocols with positive results had been obtained. The documentation had been completed, the analysis needed to obtain certificates of conformity for factory production control and welding quality was carried out.Submerged arc welding is often used for highly responsible butt joints, particularly when joining thick components. This has been achieved through the proper design of the preparation of the parts to be welded and the development of a welding technology that practically eliminates the pre-phase that occurs in traditional technology, thereby eliminating the risk of it affecting the quality of the welded joint.During the implementation of submerged arc welding, a number of technological problems were encountered. The first test joints contained many defects, i.e. sticking and slag inclusions inside the welds. In addition, obtaining welds with the correct profile and removing the slag from the weld groove was difficult. These obstacles were eliminated experimentally by carrying out successive tests using different parameters and welding groove geometries.The correct implementation of any welding process depends on its input parameters. These parameters include welding current, welding speed, welding current, wire diameter, welding voltage and many others. Submerged arc welding (SAW) is widely used in the industry for manufacturing as it is more reliable, provides deep penetration in the work, ensures a smooth finish on objects, and results in high productivity.The technology was developed for a company that manufactures control discs for steam turbines.

Mechanical Properties and Microstructure of Austenite—Ferrite Duplex Stainless Steel Hybrid (Laser + GMAW) and SAW Welded Joint

The purpose of the research was to develop a technology for producing thick-walled duplex steel welded joints. The material used in the research was X2CrNiMoN22 duplex steel in the form of a 15 mm thick plate. The welded joint was produced by the modern, high-performance Hybrid Laser Arc Welding (HLAW) method. The HLAW method involves welding a joint using a laser, the Gas Metal Arc Welding (GMAW) method and the Submerged Arc Welding (SAW) method. The HLAW method was used to make the root pass of the double butt welded joint, while the filler passes were made by the SAW method. The obtained welded joint was subjected to non-destructive and destructive testing. The non-destructive and macroscopic tests allowed the joint to be classified to the quality level B. Microscopic examinations revealed the presence of ferritic-austenitic microstructure in the base material and the weld, with different ferrite content in specific joint areas. The analysed joint had high strength properties (tensile strength (TS) ~ 790 ± 7 MPa) and high ductility of weld metal (~160 ± 4 J) heat-affected zone (~216 ± 26 J), and plasticity (bending angle of 180° with no macrocracks). At the same time, hardness on the cross-section of the welded joint did not exceed 280 HV10.

Investigation of the Effect of Solid Wire and Flux Combinations Used in Submerged Arc Welding of the LPG Cylinders on Mechanical Properties

Liquefied petroleum gas (LPG) cylinder is a type of pressure vessel that used to store and transport liquefied gases. In this study, S460MC steel with a thickness of 1.50 mm and submerged arc welding method were used in the manufacturing of LPG cylinders. Selection of the welding consumables (wire, flux) and optimization of the welding parameters (current, voltage, travel speed) are the primary focus of the study. Selected welding parameters have been verified as a result of visual and radiographic (X-ray) tests and macroscopic examinations. In order to analyze the effects of welding consumables on mechanical properties, test specimens were prepared, then tensile and hardness tests were performed and it was observed that molybdenum element increased the mechanical strength. In order to fulfill the requirements of the LPG cylinder production standard, bursting & volumetric expansion tests and pressure fatigue tests were performed and the requirements were met.

The effects of post weld heat treatment for welded high-Mn austenitic steels using the submerged arc welding method

The high-Mn austenitic steels exhibit fully austenitic structure at room temperatures while showing twinning mechanisms during deformations. In the SAW welding process, the microstructure and mechanical properties of heat affected zone (HAZ) and weld metal (WM) are affected by the welding heat causing potential degradation of mechanical properties due to the segregation and depletion of Mn in HAZ and WM regions. In this study, post weld heat treatment (PWHT) was performed at 800 °C, 900 °C and 1000 °C to improve the mechanical properties of welded high-Mn austenitic steels. We examined electron backscattered diffraction (EBSD) and energy dispersive X-ray spectroscopy (EDS) analysis to investigate the relationship between microstructure and mechanical properties after heat treatment. In particular, mechanisms of impact toughness improvement was identified by analyzing the microstructure and deformation behavior such as mechanical twin and grain size through the instrumented Charpy impact test and EBSD analysis.

Welding Thermal Cycles of Joints Made of S1100QL Steel by Saw and Hybrid Plasma-Mag Processes

Abstract The aim of this article is to validate the method of conducting a multipoint temperature measurement in the area of welded joints as a tool for quality assessment of the joints in question. In order to establish a relationship between temperature readout at a given point, the value of heat input and the distance of the point form the weld axis, preliminary tests have been conducted on a set of padding welds. Correlation of measurement data analysis showed the high 0.99 level. In the second stage of the study, temperatures of joints welded with two different methods have been measured: the HPAW (Hybrid Plasma – Arc Welding) and classic SAW (Submerged Arc Welding) method. The obtained temperature curves reflect the intensity of heat input in a given welding process. When compared to thermal effects on metallographic specimens, the shapes of the curves show a potential for quality assessment of joints in production conditions. Estimating thermal effects with classic analytical methods proves imprecise with respect to advanced high-power welding processes. Monitoring temperature will allow to assess the quality of joints in the course of welding, which may be a remarkable factor in terms of limiting the HAZ (heat affected zone) tempering of joints made from MART steels (advanced high strength martensitic steel) – a phenomenon that exceedingly decreases the strength of the joints. The method for quality assessment of welded joints presented in this paper allows to extend the analysis of welding thermal conditions.

Investigation of microstructure and mechanical properties of AISI2205/DIN-P355GH steel joint by submerged arc welding

• In this study, AISI 2205 duplex stainless steel materials and P355GH pressure vessel steels are joined by using the same additional metal and powder, with the same parameters and submerged arc welding method. • Welded with SAW method, these materials were tested by eye, magnetic particle and radiographic examination methods to detect surface and sub-surface defects. No pores, voids or cracks were found in the materials after the magnetic particle test and radiographic test. In addition, solid spot and fixation of the welded samples worked, and welded samples showed no unacceptable angular distortion and high-low defect error. • Tensile, bending, impact notch and hardness tests were applied to determine the mechanical properties of welded samples. When the tensile test results are examined, it is seen that although the highest tensile strength of the main materials is in AISI2205 material, % elongation values are very close to each other. • Successful results have been achieved from all SAW of duplex stainless steel and pressure vessel steels. This result shows that additional metal, welding flux and welding parameters are suitable for joining duplex stainless steel and pressure vessel steels. In this study, duplex stainless (AISI2205) steel and pressure vessel (P355GH) steel have been joined by submerged arc welding method (SAW). Three different joining operations (AISI2205-AISI2205), (P355GH-P355GH) and (AISI2205-P355GH) were performed respectively. ELOX UP 309 L submerged arc welding wire and Eliflux Bss-A submerged arc welding powder were used for joining materials. Welded materials have been tested with eye, magnetic particle and radiographic examination methods were used to detect surface and subsurface defects. Tensile, bending, Charpy impact notch and hardness tests were then performed to determine the mechanical properties of welded samples. Additionally, microstructure investigations were made to determine the structural changes in the welding zone. Various NDE technqiues were adopted to investigate the quality of the welds. As a result of tensile tests, the rupture was made of welding metal in AISI2205-AISI2205 joints and P355GH in other joints was made of base material. No visible errors were observed in the welding area after bending test. When the V-notch impact energies of the materials were compared, the highest toughness value was measured in the ITAB of AISI2205 material and the lowest toughness value was measured in the P355GH weld metal. In hardness measurements, the highest hardness value was obtained in the HAZ of the AISI2205 material, whereas the lowest hardness was measured in the P355GH base material. Microstructure studies indicated that the weld metal comprised a dendritic structure, and the grains were observed to become coarse in the region adjacent to the melting boundary on the main material side.

Circular economy practice: From industrial metal waste to production of high wear resistant coatings

Recently, recycling has become an essential issue in the industrial sector due to the soared consumption of materials and energy. One of the few possible ways to recycle metal waste is re-melting and converting the waste to new products. However, it requires a lot of energy, causes environmental contamination and is not applicable worldwide. Landfilling is no longer an option. This research paper focuses on finding an alternative way to recycle industrial waste by using the Submerged Arc Welding method (SAW) and metal waste, what is collected by manufacturing companies, in order to produce wear resistant hard-facings. When selecting metal waste, the greatest attention was given to waste of alloys with carbide forming elements. Turnings, shavings, and chips, as well as debris of high speed tool steel (HS6-5-2), ledeburitic high chromium cold work steel (X210Cr12), cast iron chips, waste of boron carbide B4C, worn grinding wheels (SiC), sintered hardmetal (H123, HG30) all were chosen as the remedy for reinforcement. Five possible compositions of above mentioned waste were discussed and tested on wear. SAW technique with properly chosen parameters: current 180–200 A, voltage 22–24 V, travel speed – 14.4 m/h was adapted for the production of hard-facings. Two methods to introduce waste metal powder to the weld zone were utilized: spreading of powder over the surface of substrate, and mixing with standard flux. Hard-facings obtained from waste materials were tested on abrasive emery wear. Volume-wear loss in most cases was compared to commercial steel grades. Wear results confirmed expectations as wear resistance of waste based hardfacings ∼2 times exceeded the wear resistance of commercial alloys.

Influence of Different Heat Input on Submerged Arc Welded Joints of High Strength Low Alloy Steel SX780CF

SX780CF is a new type domestic high strength low alloy (HSLA) steel with tensile strength of 800 MPa, which was used firstly for pressure pipes in the hydropower unit. In order to improve the efficiency, SX780CF is generally welded by submerged arc welding (SAW), and a kind of special intelligent welding machine for large-scale pressure steel pipe was adopted, which can realize intelligent mechanized grouping and automatic welding in tunnel. In this paper, two different levels of heat input were used to weld SX780CF. The weldability of two joints was analyzed, the mechanical properties of the joints were measured, and the hardness distribution of the joints was tested. Meanwhile, the microstructure was observed. The results show that the properties of these joints welded by two different levels of heat input could satisfy the demand of the GB 50766 -2012 standard. The mechanical properties of the weld joint with larger heat input were slightly higher than those with smaller heat input. The hardened tendency of SX780CF is small, however, the steel with the thickness of 60 mm needs to be preheated at more than 112°C. Comprehensive comparison shows that the submerged arc welding method with larger heat input has better efficiency and cost advantage, and it is worthy of promotion in hydropower project.

Analytical model of stress field in submerged arc welding butt joint with thorough penetration

Analytical model of temporary and residual stresses for butt welding with thorough penetration was described assuming planar section hypothesis and using integral equations of stress equilibrium of the bar and simple Hooke’s law. In solution the effect of phase transformations (structure changes and structural strains) has been taken into account. Phase transformations during heating are limited by temperature values at the beginning and at the end of austenitic transformation, depending on chemical composition of steel while the progress of phase transformations during cooling is determined on the basis of TTT-welding diagram. Temperature values at the beginning and at the end of transformation are conditioned by the speed of heating. Kinetics of diffusional transformation is described basing on Johnson-Mehl-Avrami-Kolmogorov equation, while martensitic transformation, basing on Koistinen-Marburger equation. Stresses in elasto-plastic state are determined by iteration, using elastic solutions method with changeable longitudinal modulus of elasticity, conditioned by stress-strain curve. Computations of stress field have been conducted for one-side butt welded of two steel flats made from S235 steel. It has enabled a clear interpretation of influence of temperature field and phase transformation on stresses caused by welding using Submerged Arc Welding (SAW) method.

Investigation of Mechanical Strength and Distortion in Submerged Arc Welding of AH36 Ship Steel Plate

A lot of research has been conducted on welding techniques and appropriate materials to reduce manufacturing time and costs without compromising on desired mechanical properties in shipbuilding. One of them is about reducing dimensional shrinkage after welding process. Shipbuilders achieve this phenomenon by applying overall redundancy of the mismatch between the design and dimension of plates which is formed due to the welding shrinkage during joining of two parts. This situation adds significantly to the material cost when the entire ship is considered. Therefore, it is important to study the stability of welding parameters to achieve a high-quality welding. In this study, welding strength and distortion have been investigated for AH36 ship steel plate joined by submerged arc welding method. In this context, 18 experiments have been conducted using two different gap sizes, with ceramic back plate and double-sided welded without ceramic under the same welding groove, and also different welding methods, currents, welding speeds, and voltages. All welding grooves of samples were prepared as 45° V type after computer numerical control (CNC) cutting. Specimens for mechanical tests were cut with abrasive water jet cutting technique in order not to affect the weld metal and heat-affected zone. According to tensile test results, fractures in all specimens occurred outside the welding zone of the base metal. It was concluded that double-sided welding method increases the welding strength. 1. Introduction Despite the availability of other transportation methods such as land and air transportations, marine transportation is one of the most preferred and widely used transportation methods in the world due to its economic advantages. Today, more than 95% of world's trade is still provided by marine transportation (Yilmaz & Tümer 2009). Therefore, manufacturing ships is crucial, and the most preferred production type is welded joints. In this respect, high weldability of the material used in ship construction has vital importance (Ay et al. 2003). The shipbuilding industry requires technological advances, such as research in welding techniques and selection of appropriate materials, to reduce processing time and costs without impairing the desired mechanical properties. Recently, researchers have focused on research and development of high-strength low-alloy (HSLA) steels, as well as the investigation of various factors that influenced their weldability (Ribeiro et al. 2016). Many different types of steel, particularly plates of A grade steel, are used mostly in shipbuilding. The quality, security, and costs of metallic ships mostly depend on the design and mechanical properties of the welded joints of ships (Yilmaz & Türner 2009). In ship construction, welded joints are regarded as weak and critical regions (Özden 2003). As some features such as higher welding penetration, corrosion and fatigue resistance, and surface quality of welded joints are to be considered in ship construction, submerged-arc welding (SAW) is one of the most critical welding processes accepted in the world (Asarkaya 2004).

Effect of Different Current Values on Microstructure and Mechanical Properties of Microalloyed Steels Joined by the Submerged Arc Welding Method

In this study, microalloyed steels were joined by using the submerged arc welding method at different welding currents of 350 A, 400 A and 450 A. The effects of selected welding parameters on the microstructure and mechanical properties of welded materials were investigated. Tensile tests and microhardness measurements were performed. Microstructural changes have been identified in the welding zone. The results showed an increase in hardness and tensile strength depending on the current intensity. The heat affected zone was observed much wider with the increase in welding current.

Application of Expectation Maximization Method for Purchase Decision-Making Support in Welding Branch

Abstract The article presents a study of applying the proposed method of cluster analysis to support purchasing decisions in the welding industry. The authors analyze the usefulness of the non-hierarchical method, Expectation Maximization (EM), in the selection of material (212 combinations of flux and wire melt) for the SAW (Submerged Arc Welding) method process. The proposed approach to cluster analysis is proved as useful in supporting purchase decisions.

Effect of Preheating before Welding on the Microstructure and the Properties of SA213 T12 and SA387Gr11CL2 Steels Joints on the Example of a Sheet Piling

The paper presents the results of the investigations of welded joints of the tube-flat bar type made of SA213 T12 and SA387Gr11CL2 steels. The joints were produced in two variants: 1) with heating up to 200°C, 2) without heating. The materials were joined by the submerged arc welding method. The temperatures of preheating before welding were determined, and it was verified whether the empiric relations (1) and (2), used to determine the minimal temperature of heating before welding for steel, can be applied under production conditions. The produced welded joints were evaluated quality-wise. Hardness measurements were performed in the particular joint areas. Finally, the effect of preheating on the obtained joints was compared.

Role of stress in the high cycle fatigue behavior of advanced 9Cr/CrMoV dissimilarly welded joint

Abstract

Microstructural characterization and wide temperature range mechanical properties of NiCrMoV steel welded joint with heavy section

Abstract

Influence of Preheating and Heat Treatment after Welding According to the EN 13445 and ASME Code on the Hardness Level of Welded Joints for the Pressure Vessel Plates

The paper deals with an analysis of preheating and heat treatment after welding and their influence on the final hardness level in case of welded jonits for common materials applied for manufacture of pressure vessel plates. During the welding process, the higher values of hardness and simultaneously decreasing of plasticity was observed and measured in the heat affected zone. Therefore, there was necessary to preheat the base material, or to apply the heat treatment after welding, or to suggest any combination of both mentioned ways. First of all, the groups of tested plates with required parameters were chosen for the application of the submerged arc welding method (according to ČSN EN ISO 4063), and preparation of samples for hardness measurement (ČSN EN ISO 6507) as the next step. The main goal of this experiment was to determine the hardness level for two fine grained steel grades after welding with the given parameters, as well as to adjust or to eliminiate the heat treatment process (preheating, post-heating), if they are not necessary.

Development of submerged arc welding method using hot wire

In the fabrication of steel bridge, submerged arc welding (SAW) is widely utilized. In order to increase the efficiency for the production of welds, the increase in electrode such as SAW with multiple wire electrodes is effective. However, heat input also increases with increasing the number of electrode. The new welding method based on SAW method with one electrode, F-SAW, was developed in the present investigation. An electrically heated filler wire, hereafter referred to as hot wire, was inserted into the rear part of weld pool made with leading SAW electrode. By using the hot wire without arc, increase in heat input could be suppressed but the amount of weld deposit could be greatly increased. Welding speed of F-SAW for deck plate 16-mm thick became two times compared with that with ordinary SAW. In the present study, mechanical properties of the weld metal formed with F-SAW were clarified. Mechanical properties of the weld metal formed with F-SAW could be improved, compared with those with SAW. Moreover, those with F-SAW was greatly improved by selecting the hot wire and cut wire. The microstructure formed with F-SAW was so fine. The refined microstructure in F-SAW might improve the mechanical properties of the weld metal.

Development of Submerged arc Welding Method in a Vertical Upward Position

The authors have developed the submerged arc welding method in a vertical upward (PF) position which is a highly efficient method for welding vertical joints in the 9 %Ni steel inner vessel of the PC LNG storage tank. The conventional submerged arc welding is limited to flat (PA) and horizontal (PC) positions because flux is used. By developing a new welding device and welding material, this unique method has been established and stability and quality have been proven. Compared to manual metal arc welding that is mainly used for vertical joints in LNG tanks outside Japan, the mechanical properties are equivalent and efficiency is higher.

탄뎀 서브머지드 용접 공법의 용접조건에 따른 용입깊이 및 용착면적 예측

Submerged arc welding method from both sides is generally applied to the welding of main panel manufacturing process during ship construction. The tandem SAW method is applied to improve the productivity. The various weld defects that occur during tandem SAW method are melt through, incomplete penetration, undercut and overlap etc. It could be thought that the reasons for these defects are mainly lack of prediction ability for penetration depth and deposited metal area. In this research, total 5 kinds of welding factors for experiment like current of lead pole, voltage of lead pole, current of trail pole, voltage of trail pole and welding speed are adopted. Weld tests are carried out for the analysis of variation effects of these factors on penetration depth and deposited metal area. Based on the test and analysis results, it is possible to obtain the prediction equation for the effect of these factors on the amount of deposited metal and penetration depth. As per the verification of the results by additional tests, it is confirmed that the prediction equation, include a error margin of <TEX>${\pm}2mm$</TEX> for penetration depth and <TEX>${\pm}10mm2$</TEX> for deposited metal area.