Industrial Welding Research Articles

Oxy-Hydrogen Gas as a Sustainable Fuel for the Welding Industry: Alternative for Oxy-Acetylene Gas

Oxy-Hydrogen Gas as a Sustainable Fuel for the Welding Industry: Alternative for Oxy-Acetylene Gas

Industrial picosecond pulse laser welding of stainless-steel to quartz for optical applications

We report on the development of a robust picosecond laser welding process for the industrially relevant material combination of quartz and stainless steel. The process requires high numerical aperture focusing of a 6 ps 1030 nm laser through the transparent quartz onto the interface between the two materials. It is found that increased mechanical pressure applied during welding increases reliability and weld performance and with the correct choice of welding parameters parts will survive ISO standard thermal cycling and vibration testing demonstrating the suitability of the process for industrial application.

Dissimilar MIG Welding Optimization of C20 and SUS201 by Taguchi Method

This study looks at how welding intensity, speed, voltage, and stick-out affect the structural and mechanical characteristics of metal inert gas (MIG) welding on SUS 201 stainless steel and C20 steel. The Taguchi method is used to optimize the study’s experiment findings. The results show that the welding current has a more significant effect on the tensile test than the welding voltage, stick-out, and welding speed. Welding voltage has the lowest influence. In addition to the base metals’ ferrite, pearlite, and austenite phases, the weld bead area contains martensite and bainite microstructures. The optimal parameters for the ultimate tensile strength (UTS), yield strength, and elongation values are a 110 amp welding current, 15 V of voltage, a 500 mm.min−1 welding speed, and a 10 mm stick-out. The confirmed UTS, yield strength, and elongation values are 452.78 MPa, 374.65 MPa, and 38.55%, respectively, comparable with the expected value derived using the Taguchi method. In the flexural test, the welding current is the most critical element affecting flexural strength. A welding current of 110 amp, an arc voltage of 15 V, a welding speed of 500 mm.min−1, and a stick-out of 12 mm are the ideal values for flexural strength. The flexural strength, confirmed at 1756.78 MPa, is more than that of the other samples. The study’s conclusions can offer more details regarding the dissimilar welding industry.

The Dynamics Stability Judging Method for a Gantry-type Welding Robot

In order to improve the dynamic performance of gantry-type welding robot, this paper introduces the structural dynamics model and Lyapunov stability criterion of the gantry-type welding robot frame with nine degrees of freedom. The dynamic equations of the welding robot satisfy the Euler–Lagrange form, and the calculation index of welding robot Lyapunov stability is judged by matrix eigenvalues. Combining with the specific design parameters of an industrial welding robot, the motion stability of the gantry-type welding robot frame and the displacement response of the welding torch are analyzed. The influence of the change of the frame design structure on the stability of the welding torch for end effector of welding robot is discussed, furthermore, the improvement direction of vibration damping and anti-interference of welding robot system is pointed out. Finally, the dynamics simulation of the optimized gantry-type welding robot end effector is carried out by using ADAMS software, and the torque variation curve of the end effector is obtained, which provides a strong basis for the selection of motor models and the design of control system.

Learning Outcomes of Psychomotor Domains in Welding Technology: VR Welding Kit Assessment: A Systematic Literature Review

Aim. This systematic literature review aims to analyse existing studies that have investigated the impact of VR welding kits on the development of psychomotor skills, knowledge acquisition, and overall learning experience. By synthesising findings from a variety of sources, this review seeks to provide insight into the strengths, limitations, and potential areas for further research in this domain. Method. This systematic literature review involved an extensive search of electronic databases such as PubMed, Google Scholar, and IEEE Xplore to identify relevant studies that focused on the impact of VR welding kits on psychomotor skills development and knowledge acquisition. Result. Findings from a systematic literature review reveal a range of results related to the impact of VR welding kits on psychomotor skills development and knowledge acquisition. Most of the research highlights the positive effects of utilising VR technology in welding education. VR welding kits were invented to improve learners’ psychomotor skills by providing a realistic and interactive simulation environment. Conclusion. Ongoing research in this domain will be critical to refining and integrating VR welding technology into welding education and practice, ultimately positioning the industry for a future that improves productivity, safety, and competitiveness. Cognitive Value. Allowing students to practice and refine welding techniques in a safe and controlled setting, ultimately leading to increased proficiency and confidence in practical applications. The insights gained from this review have significant implications for educators, training programs, and the welding industry.

Morphographic Changes in the Electrocardiogram of Colossoma macropomum Caused by Exposure to Manganese.

Manganese (Mn2+) is an abundant chemical element in the earth's crust and is present in soil, water, and industrial environments, including mining, welding, and battery manufacturing. Manganese (Mn) is an essential metal needed as a cofactor for many enzymes to maintain proper biological functions. Excessive exposure to Mn in high doses can result in a condition known as manganism, which results in disorders of the neurological, cardiac, and pulmonary systems. The aim of this study was to assess cardiac susceptibility to manganese intoxication in Colossoma macropomum subjected to a fixed concentration of 4 mg/mL for a period of up to 96 h. This study used 45 Tambaquis (30.38 ± 3.5 g) divided into five groups of 9 animals/treatment. The treated groups were exposed to the manganese concentration for a period of 24, 48, 72, and 96 h, after which the animals' ECGs were recorded, showing heart rate, R-R interval, P-Q interval, QRS complex duration and S-T interval. The results showed that cardiac activity decreased as the contact time increased, with an increase in the P-Q and S-T intervals. This indicates that the breakdown of circulatory homeostasis in these animals was caused by contact time with manganese.

Kinematic and Parametric Modeling of 6DOF(Degree-of-Freedom) Industrial Welding Robot Design and Implementation

Kinematic and Parametric Modeling of 6DOF(Degree-of-Freedom) Industrial Welding Robot Design and Implementation

Evaluation of Health Risks in the Blood Serum of People Working in the Welding Industry as a Result of Exposure to Heavy Metals in Diyala Governorate / Iraq

General Background: The welding industry is associated with significant health risks due to occupational exposure to heavy metals. Specific Background: Workers in this industry are particularly vulnerable to toxic metals such as lead, cadmium, copper, iron, and zinc, which can lead to severe health issues. Knowledge Gap: There is limited data on the specific health risks and heavy metal concentrations in welders' blood serum in Diyala Governorate, Iraq. Aims: This study aims to identify the primary health risks associated with welding-related heavy metal exposure and to explore strategies to mitigate these risks. Methods: The study was conducted in several industrial areas in Diyala Governorate, where blood samples were collected from 40 welders and 40 control participants (employees and students from Diyala University). An atomic absorption spectrophotometer was used to measure heavy metal concentrations in blood serum. Results: Statistical analysis revealed significant differences in heavy metal levels between welders and the control group (P Value < 0.05), indicating higher exposure among welders. However, no significant differences were found within welder subgroups based on age, smoking status, and duration of exposure. Novelty: This study provides the first comprehensive assessment of heavy metal exposure among welders in Diyala Governorate, highlighting the urgent need for improved protective measures. Implications: The findings underscore the necessity for environmental and health authorities to implement rapid interventions to protect welders from heavy metal toxicity. Current protective measures are inadequate, as evidenced by elevated levels of lead, cadmium, nickel, and zinc in welders' blood serum. Enhanced protective practices and stricter regulations are critical to reducing these occupational health risks. Highlights: 1. Higher levels of heavy metals found in welders' blood compared to controls.2. No significant differences among welder subgroups by age, smoking, exposure duration.3. Urgent need for better protective measures and interventions in welding industry. Keywords: Welding industry, heavy metals, occupational exposure, health risks, Diyala Governorate

Tensile test and hardness test on FCAW-GS welding results of AB/EH36Z35 material in 3G downhill position

Welding is a crucial aspect of the modern construction industry as it allows for efficient and reliable joining of metals. The purpose of this research is to evaluate the FCAW-GS welding process on AB/EH36Z35 material in the 3G downhill position. Additionally, the study aims to analyze the tensile and hardness test results of the welding. The research utilized the FCAW-GS welding method, with tensile testing conducted by the AWS D1.1/D1.1 M:2015 standard. Hardness testing was performed using the Vickers hardness test method with a test load of 10 Kgf, following the ASTM E92:2017 standard. The results of the tensile tests demonstrate that both specimens achieved high tensile strength. Furthermore, the hardness testing indicated no significant changes in material hardness in the HAZ and Line 3 areas. Consequently, this study's findings adhere to the quality standards outlined by AWS D1.1/D1.1M:2015 and ASTM E92:2017, making them a valuable reference for industrial welding processes

OCT for automated conventional welding in the automotive industry

AbstractSimilar to laser welding, optical coherence tomography (OCT) simplifies the operation of robot‐guided, automated GMA welding by offering seam tracking capabilities thanks to its industry‐approved, standardized functions and fieldbus communication. Furthermore, OCT can monitor the quality of weld seam online by measuring the seam topography during GMA welding, eliminating the need for time‐consuming and costly off‐line weld inspection.

Оценка сварочно-технологических свойств электродных покрытий основного типа различных производителей электродов для сварки трубных деталей и сборочных единиц поверхностей теплообмена котлоагрегатов

Introduction. New grades of high-strength steels, machining and repair processes are being introduced in the power industry. At the same time manual arc welding remains the main technological process for equipment repair in conditions of thermal power plants. Welding materials used in equipment repair should provide comparable to the base metal mechanical properties of the weld. The welding industry has long faced the problem of high sensitivity of basic type electrodes to moisture absorption. High susceptibility to cold cracking caused by diffusible hydrogen and hydrogen embrittlement are major obstacles to the wider use of basic-type electrodes for high-strength steels. Hydrogen production during arc welding is the result of the presence of hydrogen in the arc atmosphere, hydrogen-contaminated filler material, or local hydrogen residues on the source material. During welding, molecular hydrogen is dislocated by the arc energy and then easily absorbed by the molten material. Currently, the welding materials market produces electrodes with basic coating of well-known and proven brands, various national and foreign manufacturers. However, in practice there are cases of cold cracks in the weld seam after welding. Purpose of work is to assess the welding and technological properties of basic type electrode coatings of different manufacturers. The work investigates specimens weld overlaid with electrodes TMU-21U, TSU-5 of different manufacturers and the content of diffusion-mobile hydrogen in the weld overlaid metal is determined. The methods of research are mechanical static tensile tests, chemical composition analysis and metallographic studies. Determination of welding-induced hydrogen content can be accomplished by various quantitative elemental analysis methods. All test methods involve welding under defined conditions followed by deep freezing of the test specimens as quickly as possible. In this way, unintended diffusion processes are inhibited and the hydrogen introduced into the weld metal is retained. Subsequently, the diffusing hydrogen is desorbed from the test specimens in a controlled manner. Results and Discussion. An assessment of welding engineering properties of the electrodes revealed unstable arc burning. Mechanical properties of the welded metal of the investigated electrodes are at the minimum permissible level from the requirements of normative documents. The concentration of hydrogen present in the arc weld metal is multifactorially dependent on the welding procedure (process and parameters, consumables used, as well as environmental conditions (e.g. humidity). For qualitative assessment, hydrogen content of more than 15 cm3/100 g is considered high and hydrogen content less than 5 cm3 ml/100 g is considered very low. Presented results. The conducted evaluation of welding engineering properties of electrodes with basic coating showed satisfactory results. Mechanical properties of the welded metal in terms of impact toughness are at the lower permissible limit, relative elongation does not meet the requirements of normative documents. The content of diffusion-mobile hydrogen in the welded metal is higher than the declared indicators by the electrode manufacturers.

Research on electronic optical monitoring technology and system design for vacuum electron beam welding process

Electron beam welding technology is increasingly used in industrial manufacturing due to its high power density and the purity of welded joints. In vacuum environments, traditional optical and machine vision monitoring methods are susceptible to contamination by metal vapors, which hinders the monitoring effect. Due to the limitations of optical monitoring methods, electronic optical imaging technology is a new alternative monitoring method that has been introduced into the electron beam processing in recent years, but the complexity of the industrial electron beam welding environment makes it relatively less studied in the field of electron beam welding. In this study, a YAG scintillator detector is proposed to collect the backscattered electron information generated by the interaction of electrons with the sample, and an FPGA real-time processing system is used to realize the weld quality monitoring in the industrial electron beam welding processes. The distribution law of backscattered electrons in space is simulated by Monte Carlo method, and the results show that the number of distribution in the 40°∼60° angle region is more, the backscattering coefficient increases with the increase of the incident angle of the electron beam, and the backscattering coefficient of the samples with large atomic numbers is relatively high. The field monitoring experiments show that the designed system exhibits good sensitivity to the characteristic morphology, and the imaging resolution reaches more than 200 μm, and the weld hole defects are clearly visible. A good linear correlation between the current change curve during scanning and the actual shape profile is shown, while the image resolution is better when the spot current is 1 mA.

Deep convolutional neural network for weld defect classification in radiographic images

The quality of welds is critical to the safety of structures in construction, so early detection of irregularities is crucial. Advances in machine vision inspection technologies, such as deep learning models, have improved the detection of weld defects. This paper presents a new CNN model based on ResNet50 to classify four types of weld defects in radiographic images: crack, pore, non-penetration, and no defect. Stratified cross-validation, data augmentation, and regularization were used to improve generalization and avoid over-fitting. The model was tested on three datasets, RIAWELC, GDXray, and a private dataset of low image quality, obtaining an accuracy of 98.75 %, 90.255 %, and 75.83 %, respectively. The model proposed in this paper achieves high accuracies on different datasets and constitutes a valuable tool to improve the efficiency and effectiveness of quality control processes in the welding industry. Moreover, experimental tests show that the proposed approach performs well on even low-resolution images.

Development of a vision system integrated with industrial robots for online weld seam tracking

This paper develops a laser-structured light vision system for the industrial welding manipulator. The designed structured light vision system consisting of a line laser projector and an industrial camera is a decent 3D object data acquisition platform. By applying the principle of triangulation, the depth value of the object can be obtained via the laser plane in the captured image. According to hand-eye calibration and the principle of triangulation, the 3D position of the objects in the robot coordinate system is calculated. Based on the discriminated convolution tracker and deep reinforcement learning that increases the accuracy and processing time of the tracker, allowing simultaneous scanning for seam data acquisition and welding along the weld path, a real-time seam tracking algorithm is developed to handle the square-groove butt joint with small gaps (i.e., <1 mm). Experiments are undertaken using a Yaskawa industrial welding robot integrating the designed laser-structured light vision system. Experiment results show the significant performance of the developed system in welding square-groove butt joints with curved profiles and small gaps, i.e., the welding absolute mean error is 0.31 mm, whereas in the case of using convolution tracker only, the welding absolute mean error 1.7 mm.

The effect of heat input on tensile strength, Vickers hardness, and microstructure on DMW of AISI 1015 and 304L SS through the GMAW process

This experiment was to evaluate the effect of heat input on tensile strength, Vickers hardness, and microstructural observations.The materials welded are AISI 1015 and 304L SS, and the joining process is Gas Metal Arc Welding (GMAW). The filler electrode used is ER70S-6 with a diameter of 1.2 mm, and the workpiece size is 300 x 125 x 3 mm with a butt-joint connection. The variations in welding current applied are 120, 130, and 140 A. Meanwhile, the voltage and welding speed in the experiment were kept constant.The maximum tensile test index was 380.08 MPa, and the Vickers hardness index was 376.85 HV, with the maximum heat input being 0.5943 kJ/mm. The macro- and microstructure, as well as structural inspection of the welded joints, were observed in the experiment. The best heat input effect for the DMW technique between 304L SS and AISI 1015 is 0.5943 kJ/mm at a plate thickness of 3 mm.Dissimilar Metal Welding (DMW) is widely applied in the power generation industry. Materials generally joined using the DMW technique are austenitic stainless steel (304L SS) and low carbon steel (AISI 1015).Using the proposed heat input approach is important for the dissimilar welding industry application to obtain the right product for its expected use.This paper presents the differences in heat input to reveal the weld properties by dissimilar welding processes, where the properties will be adapted for a particular use. Particularly in the application of dissimilar joints between 304L SS and AISI 1015 with a thickness of 3 mm, which requires an average tensile strength of around 380.08 MPa and an average yield strength of about 320.16 MPa, the heat input parameter can be recommended as 0.5943 kJ/mm.

Prevalence of noise-induced health hazards and occupational safety practices among welders in Mysuru city: a cross-sectional study

Background: Occupational exposure to noise is a significant concern in the welding industry, posing potential health hazards to workers. This study aimed to assess the prevalence of noise-induced health hazards, knowledge regarding these hazards, and the practice of preventive measures among welders in Mysuru City. Methods: A cross-sectional study was conducted and data was collected from welders in Mysuru City, including noise exposure levels, perceived stress levels, insomnia prevalence, and demographic characteristics. The association between the number of years of noise exposure and auditory/non-auditory health effects was analysed. Participants' awareness of noise-induced health hazards and the use of protective equipment were also evaluated. Results: The study included male participants, predominantly below 30 years of age, with a majority (74.3%) belonging to the Muslim community. Decreased hearing (11.5%) and sleep disorders (3%) were reported by participants. About half (53.7%) were aware of noise-induced health hazards, with a high usage of safety glasses but limited use of earplugs. Most had exposure to noise for less than 5 years. Moderate levels of perceived stress and low prevalence of insomnia were observed. Significant associations were found between the number of years of noise exposure and both auditory/non-auditory health hazards, as well as between age category and auditory health effects. Conclusions: The study reveals the prevalence of noise-induced health hazards among welders in Mysuru City and highlights the importance of promoting occupational health and safety measures. Raising awareness and encouraging the use of protective measures are crucial to mitigate the adverse effects of noise exposure in the welding industry.

DETERMINANTS OF OCCUPATIONAL HEALTH AND SAFETY IN THE FOCUS OF WELDERS

The welding industry is known for having significant occupational health risks. For this reason, the occupational hazards of welders have been previously examined by many researchers in the literature. However, the traditional hazards-outcomes focused analyses do not show the big picture in which occupational health and safety (OHS) is neglected due to global competitive conditions. Therefore, it may be important to define the determinants of OHS that deepen inequalities, especially in developing countries. This study aimed to evaluate the relationship between OHS indicators and OHS determinants among welders in a developing country. In this descriptive study, the data were collected from 88 welders by telephone interview. Health outcomes were also confirmed from clinical records. In addition to the indicators of OHS, independent variables such as education level, sector, business size, union membership, security, wage, weekly working hours, etc were investigated in the study. According to the results, the work accident rate was higher in welders who started their careers as a child. Leading OHS indicators were found to be significantly worse in the working environments of those with low education, low wages, workers in the private sector and who are non-unionized. Additionally, a positive correlation was found between being unionised and high education level, high socioeconomic development (SED) level, business size, and working in the public sector. There was a negative correlation between union membership and weekly working hours. Since the concept of OHS is related to many factors, working life should be considered from a holistic perspective.

Multi-objective optimization of FSW variables on joint properties of AA5754 aluminum alloy using Taguchi approach and grey relational analysis

Friction stir welding (FSW) processing of the joint is a technique to improve the quality of the weld. The present research employed the friction stir welding technique to butt-weld AA5754 plates, whereby the joints of every weld case were identified based on their tensile strength, hardness, and impact toughness. The plates were joined by varying the rotational speeds, welding speeds, and tool tilt angles. A multi-objective optimization Taguchi’s design of experiments approach and grey relational analysis (GRA) were used in this study to assess the combined effects of the process variables. The developed models are evaluated for sufficiency, and then the most significant parameters are determined using the analysis of variance (ANOVA). The results of the ANOVA showed that the rotational speed has a maximum contribution of 55.24%, 59%, and 46.27% in obtaining the optimal values of tensile strength, hardness, and impact toughness, respectively. It was found that formability and mechanical behaviors increased with increasing tilt angle for the tilt angle range examined in the current study. The two methods provide the same results, and the optimal conditions are a rotational speed of 1000 rpm, a welding speed of 60 mm/min, and a tilt angle of 2.5°. The optimal values for tensile strength, hardness, and impact toughness, respectively, were found to be 136 MPa, 85.25 HV, and 13 J. Significant implications for the welding industry may arise from the highly favorable outcomes in terms of microstructure and mechanical attributes.

Review on Hybrid Welding Techniques for Improved Joint Performance

The process of welding is extensively employed in diverse industrial sectors for the purpose of material joining. The integrity of components or structures is significantly dependent on the quality and performance of welded joints. Nevertheless, conventional welding techniques present certain restrictions, including reduced welding velocity, substandard joint characteristics, and deformation. Hybrid welding techniques have surfaced as a viable solution in recent times to address the limitations and enhance the joint performance.The present study provides a thorough examination of diverse hybrid welding methodologies, encompassing laser-arc hybrid welding, friction stir welding, and hybrid laser welding. The manuscript examines the operational mechanisms, benefits, and constraints of every method. Moreover, the paper presents findings from recent research studies that have examined the collective efficacy of these methodologies across various materials and contexts.The findings indicate that the utilisation of hybrid welding methods has the potential to enhance joint performance through the improvement of mechanical properties, reduction of defects, and minimization of distortion. The manuscript additionally examines the obstacles and prospective avenues in the realm of hybrid welding. The research presented herein offers significant insights for both researchers and practitioners operating within the welding industry. Specifically, it provides guidance on the selection of optimal welding techniques for applications, as well as the optimisation of welding parameters to enhance joint performance.

Path Optimization in Robotic Welding of Plate Heat Exchangers: An Improved Ant Colony Approach

In industrial robot welding heat exchanger plate route planning, there are drawbacks to using the traditional ant colony algorithm (ACA), including poor search efficiency and a propensity to trend toward the local optimum. To address the above issues, first of all, the article introduces the improved pheromone volatilization factor, which is adjustable based on iteration times in the ACA. Secondly, it combines the new perturbation strategy and the cross‐mutation operation, proposes an improved genetic algorithm, and fuses it into the ACA, which increases the diversity of the ACA’s path searching and improves the ability of the local and global search. Finally, the improved ACA mechanism is verified by experiments and compared with six existing path planning algorithms (including three ACA variant algorithms and three mainstream algorithms). The experimental results show that the IACAG algorithm has excellent performance in welding heat exchanger path planning and can achieve lower calculation time and iteration times under the conditions of optimal solution and zero deviation, showing comprehensive advantages in solution quality, stability, and efficiency.