Análise e melhoria do processo de soldagem com eletrodo revestido na caldeiraria da UTE Iolando Leite – Sergipe - Brasil / Analysis and improvement of the welding process with coated electrode in the boilerwork of UTE Iolando Leite – Sergipe -Brasil

The occupational risk assessment of a machine building company must cover each activity and workstation, taking into account each component of the production system (work system), each workload, work equipment and the work environment. This assessment is an extremely complicated and complex issue since the production system of such an enterprise is particularly complex and complicated. Welding assembly is a highly polluting technology process, especially of the atmosphere and soil. The formation of gases in the welding process is the result of burning of the electrodes, powders, forming the molten metal bath and making the weld seam. Welding operators are exposed to smoke and toxic gases resulting from the welding process, which can in many cases be hazardous to health. Many acute intoxications that may be caused by excessive exposure to or short exposure to smoke and gas resulting from the welding process have been studied over time. In the paper are presented the elements of risk related to the welding process and the most widespread occupational diseases that can occur in the ranges of the welding operators. The following are presented the noxious emissions from welding and are determined by a practical method the emission of noxious at welding deposition of a welding sample, using the manual arc welding process with coated electrode.

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Strengthening Mechanism of TiB2-TiC Complex Phases Coated Electrode

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.433-440.251 ◽

2012 ◽

Vol 433-440 ◽

pp. 251-255 ◽

Cited By ~ 2

Author(s):

Ping Luo ◽

Shi Jie Dong ◽

Zhang Qiang Mei ◽

Zhi Xiong Xie

Keyword(s):

Failure Mechanism ◽

Current Density ◽

Spot Welding ◽

Single Phase ◽

Welding Process ◽

Strengthening Mechanism ◽

Galvanized Steel ◽

Steel Weld ◽

Galvanized Steels ◽

Coated Electrode

TiB2-TiC complex phases coating deposited onto the surface of electrodes by electro-spark deposition (ESD) in order to prolong the life of single phase coated electrode (TiB2 or TiC) during resistance welding of galvanized steels. The microstructures and TiB2-TiC complex phases coatings were characterized by SEM and XRD. The results indicate that life of TiB2-TiC complex phases coated electrode is prolonged significantly than life of single-phase coated electrode （TiB2 or TiC ）, failure mechanism of TiB2-TiC complex phases coated electrode is mainly wear to cause diameter increase on electrode tip, which results in lower current density during welding process, and then nugget size cannot satisfy the requirement of resistance spot welding. The failure mechanism of TiB2-TiC complex phases coated electrode is obviously different from uncoated electrode, the failure mechanism of uncoated electrode is wear and alloying between electrode tip surface and molten Zn on galvanized steel weld surface.

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Determination of Some Mechanical Properties of Welded Reinforcing Steel with Self-Shielded Wires by Vibration Tests

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1029.206 ◽

2014 ◽

Vol 1029 ◽

pp. 206-211 ◽

Cited By ~ 2

Author(s):

Liviu Bereteu ◽

Mircea Burcă ◽

Raul Moisa ◽

Dorin Simoiu ◽

Gheorghe Drăgănescu ◽

...

Keyword(s):

Mechanical Properties ◽

Welding Process ◽

Steel Reinforcement ◽

Reinforcing Steel ◽

Coated Electrode ◽

Major Disadvantage ◽

Steel Bars ◽

Vibration Tests ◽

The Cost

Reinforced concrete is a material formed by pouring concrete over reinforcement steel bars and wires and sometimes by a polymer that turns by drying in a hard and rigid composite. Welding of steel reinforcement concrete is a relatively difficult operation and with a large amount of work, given by the large number of welds that are needed and when this work is make in site conditions. The most common method of steel reinforcement welding is manual welding with coated electrode. The major disadvantage of this process is low productivity in welding effects on execution time, and the cost of welding. An alternative to manual welding with coated electrode for steel reinforcement welding on site is the welding process with self-shielded tubular wires.The aim of this paper is to determine the mechanical properties of welded reinforcing steel PC 52 with self-shielded wires, using a vibroacustic technique. To validate this method, the results obtained by vibroacoustic signal processing are compared with those determined by the tensile stresses of the same samples.

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Visualization of the Coated Electrode Welding

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun201664010043 ◽

2016 ◽

Vol 64 (1) ◽

pp. 43-51

Author(s):

Michal Černý ◽

Petr Dostál ◽

Michal Šustr

Keyword(s):

Acoustic Emission ◽

Chemical Composition ◽

Welding Process ◽

Non Destructive Testing ◽

Destructive Testing ◽

Mechanical Verification ◽

Joint Formation ◽

Coated Electrode ◽

The Impact ◽

Non Destructive

This work is dedicated to the evaluation of the welding process in terms of assessing the impact of weldability based on the recording of the non-destructive testing of the acoustic emission (AE). Measurements are performed utilising both materials with guaranteed weldability and materials with reduced weldability. In addition to welding, the thesis also discusses the material (metallographic and fractographic) and mechanical verification of joint formation and the variations in behaviour of metals of differing chemical composition. It also includes an analysis of AE records in relation to the condition of the material during the developing of fusion and resistance joints.

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THE IMPACT OF PADDING WELD SHAPE OF AGRICULTURAL MACHINERY TOOLS ON THEIR ABRASIVE WEAR

Tribologia ◽

10.5604/01.3001.0014.3740 ◽

2020 ◽

Vol 290 (2) ◽

pp. 55-62 ◽

Cited By ~ 1

Author(s):

Dawid ROMEK ◽

Jarosław SELECH ◽

Dariusz ULBRICH ◽

Agata FELUSIAK ◽

Piotr KIERUJ ◽

...

Keyword(s):

Chemical Composition ◽

Abrasive Wear ◽

Laboratory Tests ◽

Welding Process ◽

Agricultural Machinery ◽

Weld Shape ◽

Second Stage ◽

Coated Electrode ◽

The Impact

The paper presents laboratory tests results of wear in the abrasive mass of cultivator coulters subjected to coated electrode pad welding. In the first stage of the test, one type of electrode was used and a padding weld was applied to the coulter surface in three different shape variants (perpendicular, parallel to the abrasive mass stream and V-shaped). The lowest abrasive wear was obtained for samples with a padding weld deposited perpendicularly to the abrasive mass stream. Therefore, in the second stage of the research, this padding weld shape was selected and made using three different electrodes. Tests of abrasive wear both in the first and the second stage of the experiment were carried out at a distance of 100 km by the "rotating bowl unit" method. Both the direction of the application of the padding weld (shape) and the chemical composition of the electrode used in the pad welding process significantly increased the resistance to abrasive wear compared to coulters whose surface has not been welded.

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INFLUENCE OF DIFFERENT ASSEMBLIES ON PRE-HEATING THE HSLA SAR 80T STEEL ON COATED ELECTRODE WELDING

Revista de Engenharia Térmica ◽

10.5380/reterm.v19i2.78612 ◽

2020 ◽

Vol 19 (2) ◽

pp. 40

Author(s):

J. S. Bastos ◽

C. A. M. Ferreira ◽

M. C.L. Souza ◽

J. S. Dias ◽

N. C. O. Tapanes

Keyword(s):

Alloy Steel ◽

Cost Reduction ◽

Welding Process ◽

High Strength ◽

Time Cost ◽

Low Alloy Steel ◽

Preheat Temperature ◽

Cross Sectional ◽

Coated Electrode ◽

Visual Testing

The present work evaluated the influence of assemblies other than preheating in the welding process obtained by coated electrode, using high strength and low alloy steel SAR 80T as the base metal and the AWS E7018 electrode as the addition metal. In order to prevent cracks, preheating and interpassing for low alloy steel was performed. Depending on the way the preheating equipment is installed, it may take more or less time to reach the preheat temperature. Different assembly arrangements for top joints were evaluated, aiming at cost reduction, in addition to evaluations of the mechanical properties of the joint. Visual testing, ultrasound, micrography, macrography and cross-sectional traction were performed. The results obtained were considered acceptable and showed that there was an influence on time, cost of preheating and resistance to impact.

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Effects of bottom plate in friction stir welding of AA6061-T6

Metallurgical Research & Technology ◽

10.1051/metal/2020087 ◽

2020 ◽

Vol 118 (1) ◽

pp. 108

Author(s):

M.A. Vinayagamoorthi ◽

M. Prince ◽

S. Balasubramanian

Keyword(s):

Mechanical Properties ◽

Axial Load ◽

Weld Zone ◽

Welding Process ◽

Bottom Plate ◽

Welding Parameters ◽

Nugget Zone ◽

Friction Stir ◽

Weld Joints ◽

Fine Grain

The effects of 40 mm width bottom plates on the microstructural modifications and the mechanical properties of a 6 mm thick FSW AA6061-T6 joint have been investigated. The bottom plates are placed partially at the weld zone to absorb and dissipate heat during the welding process. An axial load of 5 to 7 kN, a rotational speed of 500 rpm, and a welding speed of 50 mm/min are employed as welding parameters. The size of the nugget zone (NZ) and heat-affected zone (HAZ) in the weld joints obtained from AISI 1040 steel bottom plate is more significant than that of weld joints obtained using copper bottom plate due to lower thermal conductivity of steel. Also, the weld joints obtained using copper bottom plate have fine grain microstructure due to the dynamic recrystallization. The friction stir welded joints obtained with copper bottom plate have exhibited higher ductility of 8.9% and higher tensile strength of 172 MPa as compared to the joints obtained using a steel bottom plate.

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