Increasing the Quality of Welded Joints of Al-Si 6082 Alloys by Introducing Forced Vibrations

2017 ◽  
Vol 907 ◽  
pp. 231-237
Author(s):  
Mihai Alexandru Bodeanu ◽  
Teodor Machedon-Pisu
Keyword(s):  
Longitudinal Vibration ◽  
Welding Process ◽  
Solidification Process ◽  
Forced Vibrations ◽  
Major Influence ◽  
Material Structure ◽  
Welding Equipment ◽  
Welded Structure ◽  
Surface Welding

The solidification process of aluminum alloys welded area has a major influence on the quality of the joining material. Based on this fact, the introduction of forced vibrations during welding aims to prevent the formation of increase tensions inside the welded structure and diminish the presence of pinholes or pores as a result of material contraction of alloys containing metals with a different melting point / solidification point.To avoid this happening it is essential to know and control how the melted material is evolving during the solidification. This step requires that the Al-Si alloy to be welded on a surface with longitudinal vibration composed of a platform whose support can be controlled depending on the required frequency and un M.I.G welding equipment with mechanized welding torch setup to weld, the test peace, above the platform surface. Welding in a mechanical forced vibration environment, results in the formation of a more uniform and finer grain size microstructure with a more advanced diffusion in the affected zone. The diffusion process occurs faster resulting in decreased structural tensions. The presence of voids and pores inside the material structure is inferior for the oscillating welding process in comparison with the classic solution.

Multifactor mathematical model of criticality of welding process of products from aluminum- magnesium alloys

2020 ◽  
pp. 12-18
Author(s):  
F.A. Urazbahtin ◽  
A.YU. Urazbahtina
Keyword(s):  
Mathematical Model ◽  
Magnesium Alloy ◽  
Magnesium Alloys ◽  
Welding Process ◽  
Welding Equipment ◽  
Equipment Operation ◽  
Aluminum Magnesium Alloys ◽  
Aluminum Magnesium Alloy ◽  
Welding Materials

A multifactor mathematical model of the welding process of products from aluminum-magnesium alloys, consisting of 71 indicators that assess the quality of the weld, the welding process, costs, equipment operation and quality of the welded material. The model can be used to control and optimize the welding process of products from aluminum-magnesium alloys. Keywords welding, products, aluminum-magnesium alloy, indicators, process parameters, welding equipment, welding materials, electrode sharpening, lining [email protected]

scholarly journals Contributions Regarding the Use of Mechanical Vibrations in Order to Improve the Properties of Steels and Welded Joints Used in Metal Constructions

2020 ◽  
Vol 21 (2) ◽  
pp. 67-71
Author(s):  
Gheorghe Novac ◽  
Bogdan Novac
Keyword(s):  
Welded Joints ◽  
Arc Welding ◽  
Significant Contribution ◽  
Welding Process ◽  
Internal Stresses ◽  
Welding Equipment ◽  
Welding Technology ◽  
Submerged Arc ◽  
Very High

The paper presents aspects regarding the influence of vibrations on the mechanical properties of welded joints, made with basic materials of Spanish and Romanian origin. In this research is presented the practical way to make the necessary assemblies for the proposed tests. The tests show that vibrations have a significant contribution to the quality of welded joints. This is explained by the appearance of several crystallization centres which makes the structure finer. By using vibrations, the atoms are rearranged in the structure, ensuring a proper de-tensioning. The stresses induced in welded metals are significantly reduced by the use of vibration during welding process. The addition materials have a significant contribution to the emergence of stresses in welded joints as well. These stresses can contribute to the appearance of microstructural constituents with significant hardness. The welding equipment and technologies used also have a significant contribution to the emergence of the remaining stresses. For example, the submerged arc welding technology (SAF) can introduce very high internal stresses. By using vibrations during the welding process, it is achieved a fine structure and a significant reduction of remaining stresses in the welded joints.

scholarly journals FCAW vertical welding of “V” butt plate in AC UHV transmission line construction

2018 ◽  
Vol 175 ◽  
pp. 03001
Author(s):  
Han Yang ◽  
Chen Kerui ◽  
Li Yang ◽  
Qu Bao
Keyword(s):  
Transmission Line ◽  
Large Scale ◽  
Optimal Allocation ◽  
Welding Process ◽  
Steel Structure ◽  
Solid Core ◽  
Flux Cored Arc Welding ◽  
Welded Structure ◽  
Wide Range

In twenty-first Century, China vigorously promoted the research and construction of AC and DC transmission technology in order to ensure the optimal allocation of energy resources in a large scale[1]. In the construction of AC UHV transmission line, the welding quality of tower and stiffening plate as the load bearing tower and the tension of the welded structure plays an important role in the overall quality of the steel structure. In the past, the welding process of semi automatic carbon dioxide solid core welding wire often has the characteristics of weld spatter not easy to clean up and low efficiency of welding. The semi-automatic CO2 flux cored arc welding, has the characteristics of current and voltage to adapt to a wide range, melting speed, has important significance for improving the process, this paper describes the technology in practical engineering applications, and developed the basic strategy of training for grid steel structure welding technicians. This paper also lists both V groove plate butt FCAW welding typical welding project, hope this welding process will continue to spread.

scholarly journals Weld Flaw Detection Based on Likelihood Estimation and Wavelet Transform

2019 ◽  
Vol 8 (6S3) ◽  
pp. 1734-1738
Keyword(s):  
Visual Inspection ◽  
Measurement Techniques ◽  
Flaw Detection ◽  
Welding Process ◽  
Likelihood Estimation ◽  
Actual Application ◽  
Welded Structure ◽  
Relevant Domain ◽  
Huge Investment

The metals are fused at high temperature using various welding methods to form mechanical structures. The structural stability is achieved in metals by the proper welding process utilized. The failure may result in disaster and huge investment has to be incurred towards building the flawless structures. It is always preferred to check the quality of the weld before the final welded structure is used for its actual application. Though visual inspections could solve problems tentatively valid for low production rates, there are scenarios where visual inspection fails and needs high end methods to analyze the quality of welded joints. Several measurement techniques have evolved and help the user community. The objective of this paper is reviewing such earlier methods in the relevant domain of research and tabulates the various merits and demerits so as to find a method to overcome earlier drawbacks. Further, edge detection is done based on adaptive thresholding method to find the weld flaws

The Development of Control System for Lowcost Automatic Welding Equipment of Aluminum Radiator Head

2012 ◽  
Vol 485 ◽  
pp. 12-15
Author(s):  
Ju Lian Ma ◽  
Hao Bin Zhou ◽  
Xiang Qian Xu ◽  
Xiao Wei Wang
Keyword(s):  
Control System ◽  
Low Cost ◽  
Welding Process ◽  
Welding Parameters ◽  
Automatic Welding ◽  
Control Board ◽  
Manual Operation ◽  
Welding Equipment ◽  
Production Site

Considering the characteristic of welding process for all-aluminum radiator and meeting the needs of Chinese production site, low-cost automatic welding equipment for aluminum radiator head has been designed, and this paper focuses on its electrical controls. The microkernel of main control board is C8051F020. Based on this board the subsystems for the entire piece of this equipment has been established, which include LCD，automatic welding, manual operation , welding parameters setting ,etc. Through trial runs of the machine, it indicates that the design of the electrical controls for the equipment is rational, full-featured, and works reliably and efficiently. And the quality of welding is well.

Ways to improve welding operations in construction of oil product storage tanks

2020 ◽  
pp. 301-308
Author(s):  
O.I. Filippov
Keyword(s):  
Arc Welding ◽  
High Performance ◽  
Welding Process ◽  
Automatic Welding ◽  
Storage Tanks ◽  
Welding Equipment ◽  
Technical Requirements ◽  
Double Electrode ◽  
Product Storage

It is shown that in order to further increase the welding rate in the construction of oil product storage tanks, fi rst of all it is necessary to develop and implement high-performance methods for double-sided arc welding of vertical joints. It is noted that the most useful technique to increase the welding rate and the quality of vertical joints on the side walls of the tanks is to replace single-arc automatic welding with multi-arc welding in gas-shielded or gas mixtures. Whereby the method exhibiting the most promise for is the double-sided synchronous welding. In this case, two arcs on the both sides of the workpiece are involved in the weld formation. It is determined that for the formation of technical requirements for the welding process and needed welding equipment, and for their implementation in multi-arc welding of vertical joints, it is necessary to conduct comprehensive study of multiparameter relationship between the double-electrode welding modes and the quality of the welded joints in the construction of oil product storage tanks based on physical and mathematical modeling.

scholarly journals Influence of the Process Parameters on the Quality and Efficiency of the Resistance Spot Welding Process of Advanced High-Strength Complex-Phase Steels

Metals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1545
Author(s):  
Gerardo Morales-Sánchez ◽  
Antonio Collazo ◽  
Jesús Doval-Gandoy
Keyword(s):  
Shear Strength ◽  
Frequency Converter ◽  
Welding Process ◽  
High Strength Steels ◽  
High Strength ◽  
Welding Parameters ◽  
Resistance Spot ◽  
Welding Equipment ◽  
Advanced High Strength Steels

In this study, the effects of electrical characteristics of an inverter combined with main welding parameters on the resistance spot weldability of advanced high strength steels (AHSS) CP1000 is investigated. The main welding parameters, current and time, were varied. The effects on the geometry and microstructure of the weld spot, the diameter of the weld pad, the hardness, the shear strength, and the efficiency of the process were studied, and the results were compared for two switching frequencies of the medium frequency converter. Furthermore, the weldability lobes were obtained as a function of the shear strength, for both frequencies. This work shows that the quality of the welding, in the established terms, is better when a lower frequency is used, even though the parameterization of the welding equipment can be easier for higher frequencies.

Review of Welding Residual Stress Stiffening Effect on Vibrational Characteristics of Structures Using Damage Approach and Vibratory Stress Relief Implementation

2017 ◽  
Author(s):  
AmirHossein MajidiRad ◽  
Yimesker Yihun
Keyword(s):  
Residual Stress ◽  
Modal Analysis ◽  
Structural Integrity ◽  
Material Selection ◽  
Welding Process ◽  
Stress Relief ◽  
Welding Residual Stress ◽  
Welded Structure ◽  
Welding Procedure

There is a huge amount of research and study on the quality, parameter manipulation, material selection etc. of welding to develop optimized results for specific applications. To have a profound understanding of the process, and to investigate and verify various parameters which affect the quality of the welding process, experts use analytical, numerical and experimental methods. The major concern regarding the welding procedure is welding defect, which can affect the integrity of the welded structure. Various nondestructive structural health monitoring methods and modal analysis techniques have been employed to study and improve the strength and quality of the welded structure. Modal analysis is one of the most accurate and commercial techniques to track down the damage within the structures. It uses natural frequency, damping factors and modal shapes to observe the structural and material defects in details. There have been noticeable developments in this area and lots of studies have been conducted applying this technique to put welding procedure under rigorous scrutiny to improve its efficiency. While modal analysis is a tool to identify structural integrity of the components, vibration can affect the nature of the metal and change the mechanical properties in some cases. Mechanical vibration and Ultrasonic as low and high frequency oscillations respectively, are able to change the microstructure of the structures so that dislocations move, hence the stress trapped within will redistribute. This redistribution can lead to residual stress reduction up to a level. In this review paper, all remarks above are considered, defined and accurately studied through various cases in order to address different application of vibratory stress relief and recent achievement in this field.

Administrasi Hubungan Sekolah dan Masyarakat

2020 ◽  
Author(s):  
Fisma Janusuri
Keyword(s):  
Community Participation ◽  
Community Empowerment ◽  
Major Influence ◽  
Learning Achievement ◽  
Quality Of Learning ◽  
Good Schools ◽  
Education Process

Community empowerment in education is needed especially to support the implementation of good schools. The level of community participation in the education process in this school seems to have a major influence on the progress of the school, the quality of learning services in schools which will ultimately affect the progress and learning achievement of children in school.

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