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1

Finite element simulation of edge welding in a fin plate: a study incorporating experimental measurement of input factors

Sudharsanam V., Sathiya Narayanan C., Shanmugarajan B., Prakash L.

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e208, 2022

EN

The present paper discusses the finite element analysis (FEA) performed using SYSWELD software, simulating the Gas Metal Arc Welding (GMAW) of a fin plate on one of its edges. The objective of this work is to study how experimentally measured input factors contribute in the close prediction of thermal and mechanical behaviour of the edge welded fin plate, using FE simulation. The fin plate material considered is ASME SA 387 Gr 12 Cl 2 and of size 1200 mm × 50 mm × 6 mm. Three input factors required for the FEA namely the weld profile, solidus temperature, heat input of welding were identified given their possible influence on the accuracy of FEM prediction. All these factors were determined experimentally using appropriate methods. Then, using these factors as inputs, FEA of edge welding in the fin plate was performed in SYSWELD. This was followed by an experimental trial for validation purpose. The trends of thermal history, strain history and longitudinal bending distortion predicted by FEA and their closeness with the experimentally measured values have been discussed. Based on the findings, it was concluded that the experimental measurement of input factors has enabled the accurate FE simulation of edge welding in fin plate.

2

Gazy osłonowe do spawania łukowego drutem litym (MAG) stali węglowych i niskostopowych

Niagaj Jerzy

Stal, Metale & Nowe Technologie

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2019

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nr 9-10

88--92

PL

Omówiono rodzaj i skład gazów używanych podczas spawania stali niestopowych i niskostopowych metodą MAG (GMAW), jak również opisano wpływ poszczególnych gazów na proces spawania i jakość złączy spawanych.

EN

The type and composition of gases used in the MAG (GMAW) welding of carbon and low-alloy steels are discussed, as well as the influence of particular shielding gases on the welding process and quality of welded joints is described.

3

Poprawa sprawności energetycznej urządzeń spawalniczych

Stopczyk W., Nawrocki Z.

Maszyny Elektryczne : zeszyty problemowe

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2016

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Nr 3 (111)

35--40

PL

W artykule zajęto się zagadnieniem poprawy sprawności energetycznej urządzeń spawalniczych spawających metodą GMAW (Gas Metal Arc Welding). Badano wpływ rożnych rozwiązań konstrukcyjnych urządzeń na ich sprawność. Przebadano trzy podstawowe grupy urządzeń spawalniczych, reprezentujących różne rozwiązania konstrukcyjne: transformatorowe, tyrystorowe i inwertorowe. Są to typowe, obecnie produkowane urządzenia jednego z producentów profesjonalnych urządzeń spawalniczych. Rozwiązania konstrukcyjne tych urządzeń w zakresie analizowanych właściwości reprezentowały analogiczne grupy urządzeń głównych światowych producentów urządzeń spawalniczych. Pokazano, jak na tle tych rozwiązań wypada ich sprawność. Przedstawiono i omówiono wyniki badań. Wykazano zasadniczy wpływ przyjętego rozwiązania konstrukcyjnego na sprawność urządzenia spawalniczego. W dalszej części artykułu skupiono się na urządzeniach inwertorowych. Pokazano układ elektryczny spawarki rezonansowej LLC. Przedstawiono wyniki badań symulacyjnych rezonansowego urządzenia spawalniczego dla rożnych metod sterowania. Symulowano pracę urządzenia przy zastosowaniu regulacji mocy wyjściowej metodą modulacji gęstości impulsów i sterowania fazowego. Porównano straty załączania i wyłączania tranzystorów pracujących w układzie mostkowym przy zerowych i niezerowych wartościach prądu drenu i napięcia dren-źrodło. Podsumowano wyniki pomiarów i symulacji.

EN

This article addresses the topic of improving the energy efficiency of welding machines with GMAW system (Gas Metal Arc Welding). The research tested the influence of various design solutions on their efficiency. Three basic groups of welding machines were examined, with the machines representing various design solutions: transformer, thyristor and inverter. These are the typical welding machines produced currently by one of the manufacturers of professional welding equipment. Design solutions of these welding machines tested within the scope of the selected properties are equally representative of the group of welding machines produced by the global leading manufacturers of welding equipment. The proposed solutions demonstrated the efficiency of the machines. Research results were presented and discussed. It has been proved that the adopted the design solution has the major impact on the efficiency of the welding machines. Another part of the article focused on the inverter machines. Electrical scheme of the resonant LLC welding machine was presented. The results of the resonant welding machines simulation studies for various control methods were presented. The operation of the resonant welding machine for various control methods was simulated and presented. The operation of the resonant welding machine was simulated by the application of the output Power control performed by the pulse density modulation and phase control method. Next, the comparison was made between the losses of switching on and off the transistors operating in the bridge circuit at zero and non-zero values of the drain current and drain-source voltage. The results of measurements and simulations were summarized.

4

Zastosowanie układów rezonansowych w urządzeniu spawalniczym

Stopczyk W., Nawrocki Z.

Maszyny Elektryczne : zeszyty problemowe

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2014

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Nr 2(102)

43--48

PL

Rosnące koszty energii oraz problemy związane z obciążalnością źródeł energii i ochroną środowiska są powodami, dla których staje się celowe poszukiwanie nowych rozwiązań układowych urządzeń spawalniczych. Ze względu na stosunkowo duże moce znamionowe urządzeń spawalniczych, nawet niewielkie zwiększenie sprawności tych urządzeń może przynieść znaczące korzyści. Jednym ze sposobów pozwalających zwiększyć sprawność urządzeń spawalniczych są techniki rezonansowe konwersji energii. Zaletą tych układów jest eliminacja strat przełączania i wyższa częstotliwość pracy w porównaniu z układami klasycznymi. Ponadto składowe pasożytnicze, ktore powodują problemy w topologiach alternatywnych, w przypadku technik rezonansowych stają się zaletą. W artykule przedstawiono wymagania stawiane urządzeniom spawającym metodą GMAW (gas metal arc welding). Jest to podstawowa metoda spawania stosowana w przemyśle. Rozpatrzono zastosowanie szeregowego układu rezonansowego LLC w urządzeniu spawalniczym spawającym metodą GMAW. Przeanalizowano następujące metody regulacji mocy wyjściowej urządzenia spawalniczego: modulacji gęstości impulsów, modulacji szerokości impulsów (PWM), sterowania fazowego. Opracowano konstrukcję i przebadano urządzenie spawalnicze, w którym zastosowano regulację mocy wyjściowej urządzenia metodą gęstości impulsów.

EN

Rising energy costs and problems associated with load capacity of energy sources and environmental protection are the reasons for which it becomes expedient to search for new solutions of circuits welding equipment. Due to the relatively high power ratings of welding equipment, even a small increase in the efficiency of these devices can bring significant benefits. One way to increase the efficiency of welding machines are resonant power conversion techniques. The advantage of these circuits is to eliminate switching losses and higher operating frequency compared to conventional circuits. In addition, the parasitic components which cause problems in the alternative topologies – in the case of resonance techniques become – advantage. The article presents the requirements for welding devices using GMAW (Gas Metal Arc Welding). This is the basic welding method used in industry. We examined GMAW welding device with LLC serial resonant circuit. We analyzed the following methods of regulating the output power of the welding machine: pulse density modulation, pulse width modulation (PWM), phase control. We developed and tested welding machine, which uses the output power control devices using pulse density method.

5

Wpływ sposobu napawania rur kotłowych na mikrostrukturę i skład chemiczny napoin

Rozmus-Górnikowska M., Blicharski M., Kusiński J., Kusiński L., Marszycki M.

Inżynieria Materiałowa

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2014

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Vol. 35, nr 1

31--34

PL

Celem pracy była ocena wpływu metody napawania Inconelem 625 rur kotłowych ze stali P235GH i 16Mo3 na mikrostrukturę i skład chemiczny podłoża i napoiny. Badania prowadzono na odcinkach rur kotłowych napawanych stopem niklu Inconel 625 przez czterech różnych producentów stosujących różne metody napawania: CMT, GMAW i GTAW. Wykazano, że bez względu na metodę napawania otrzymane napoiny składają się z następujących stref mikrostruktury: strefy przetopionej, strefy częściowego wymieszania oraz strefy wpływy ciepła (rys. 3). W strefie przetopionej i częściowego wymieszania obserwuje się zwiększoną zawartość Fe (rys. 4). Największą zawartością Fe przy powierzchni powłoki charakteryzują się napoiny, które mają najmniej równomierną powierzchnię wtopienia oraz najmniej gładką powierzchnię zewnętrzną. Przy najmniejszym kącie pochylenia ściegu zawartość Fe zmniejsza się najszybciej w miarę oddalania się od powierzchni wtopienia w kierunku powierzchni napoiny (rys. 6).

EN

The aim of this work was to identify the impact of the cladding method of boiler pipes from P235GH and 16Mo3 steels on the microstructure and chemical composition of substrates and coatings. The investigations were carried out on boiler pipes cladded with Inconel 625. The pipes were cladded in various conditions (CMT, GMAW and GTAW) and were delivered by different suppliers. It has been shown that regardless of the cladding method, the overlays consist of the following microstructural zones: fusion zone, partially mixed zone and heat affected zone (Fig. 3). An increased concentration of Fe was observed in the fusion zone as well as in the partially mixed zone (Fig. 4). The overlays with the least uniform fusion zone and the highest surface roughness were characterized by the highest concentration of Fe. The concentration of Fe in the overlay with the smallest bead slope decreased the quickest (Fig. 6).

6

Welding Effects on the Mechanical Integrity of a Trip800 Steel: a Comparison of Laser Co2 and Gmaw Processes

Perez-Medina G. Y., Lopez H. F., Reyes-Valdes F. A., Garza-Gomez A., Lopez-Ochoa L. M.

Archives of Metallurgy and Materials

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2014

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Vol. 59, iss. 4

1427--1432

EN

In this work a strip of a transformation induced plasticity (TRIP) steel was welded using gas metal arc welding (GMAW) and Laser CO2 welding (LBW) processes and the resultant strength and ductility of the welded joints evaluated. It was found that LBW lead to relatively high hardness in the fusion zone, FZ where the resultant microstructure was predominantly martensite. The relative volume fractions of phases developed in the welded regions were quantitatively measured using color metallography combined with X-ray diffraction analyses. It was found that the heat affected zone, HAZ developed the maximum amount of martensite (up to 32%) in the steel welded using LBW besides a mixture of bainite, retained austenite and ferrite phases. In contrast, a relatively low percent of martensite (10.8%) was found in the HAZ when the GMAW process was implemented.

PL

Pas ze stali typu TRIP poddano spawaniu elektrodą topliwą oraz spawaniu laserowemu i oceniono wytrzymałość i plastyczność uzyskanych połączeń spawanych. Stwierdzono, że spawanie laserowe prowadzi do uzyskania stosunkowo wysokiej twardości w strefie łączenia, gdzie powstała mikrostrukturę stanowi głównie martenzyt. Względne udziały objętościowe faz w spawanych obszarach zmierzono ilościowo za pomocą barwnej metalografii w połączeniu z dyfrakcyjną analizą rentgenowską. Stwierdzono, że w przypadku stali spawanej laserowo strefa wpływu ciepła zawiera najwięcej martenzytu (do 32%), a oprócz tego mieszanine bainitu, resztkowego austenitu i ferrytu. Natomiast w strefie wpływu ciepła uzyskanej podczas spawania elektrodą topliwą stwierdzono stosunkowo niską zawartość martenzytu (10,8%).

7

Welding of MART steel with the use of matching fillers

Matkowski P., Nowacki J., Sajek A.

Archives of Materials Science and Engineering

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2014

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Vol. 70, nr 2

77-86

EN

Purpose: This paper attempts to determine the influence of using fillers of various kinds on strength of a welded joint of MART steel depending on the amount of heat supplied. Design/methodology/approach: Test welded joints were made of S1100QL steel with GMAW method, and using different fillers as well as different values of supplied heat. The tests were designed in such a way so as to demonstrate the prospected interdependencies as clearly as possible. Macroscopic examination was carried out, Vickers hardness, impact strength and tensile strength were measured, and technological bend test was conducted on the joint. Findings: Significant differences between the joints obtained resulting from the fillers used and welding parameters applied were noticed. The strength of a joint is lower than that of welded steel, it concentrates in the weld and is similar to the strength of parent material. Research limitations/implications: Conducting research concentrating on welding using particular filler in a wider range of heat supplied would make it possible to obtain more precise results. By delineating the interdependencies between strength parameters, it would be possible to optimise the mechanical properties of welded joints made of MART steels. It would require the employment of automated welding that allows for unrestricted and stable control of parameters. Practical implications: The conditions for making a proper joint of S1100QL steel were determined. Reasons were given for the choice of joint testing methodology and the purposefulness of comprehensive tests of joint parameters. The need for changing test procedures in order to eliminate the causes of inappropriate evaluation was manifested. The influence of automation as an important factor that determines the fulfilment of strict parameter regime of joint formation was emphasised. Determination of the interrelations between mechanical properties of a joint and welding parameters applied would allow to conduct a welding process in such a way so as to obtain a joint of desired usefulness in given technological conditions. Originality/value: Problems associated with welding of S1100QL steel with the use of filler metals of matching materials were defined and possible solutions for these problems were presented. The mechanism of welding thermal cycle influencing structural changes in the joint that result from the complex cycle of hardening and tempering was demonstrated.

8

Influence of boiler pipe cladding techniques on their microstructure and properties

Rozmus-Górnikowska M., Blicharski M., Kusiński J., Kusiński L., Marszycki M.

Archives of Metallurgy and Materials

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2013

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Vol. 58, iss. 4

1093--1096

EN

The aim of this work was to investigate different weld overlay coating technologies applied to steel boiler pipes and their influence on microstructure and properties of the produced overlays. The investigations were carried out on the boiler pipes weld overlaid by an Inconel 625 and cladded at various conditions (CMT, GMAW and GTAW). The investigations showed that microstructure and mechanical properties of overlaid pipes depend on cladding technology and the chemical composition of the base material.

PL

Celem pracy była ocena wpływu metody napawania Inconelem 625 rur kotłowych ze stali P235GH i 16Mo3 na mikrostrukturę i własności podłoża i napoiny. Badania prowadzono na odcinkach rur kotłowych napawanych stopem niklu Inconel 625. Rury zostały dostarczone do Fabryki Kotłów SEFAKO S.A. przez czterech dostawców, stosujących różne metody napawania, a mianowicie CMT, GMAW i GTAW. Badania wykazały, że mikrostruktura i własności mechaniczne rur napawanych istotnie zależą od zastosowanej metody napawania oraz od składu chemicznego materiału podłoża.

9

The effect of welding method on the structure of a welded joint

Ciechacki K., Szykowny T.

Journal of Polish CIMAC

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2012

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Vol. 7, no 3

47-52

EN

This work explains the influence of a local structural heterogeneity and resulting mechanical heterogeneity in welded joints on the location and nature of welded joint failure. Toughened structural steel S355 with a thickness of 7mm, welded using laser beam or gas metal arc welding (GMAW) was used for the purposes of this analysis. Hardness penetration pattern in welded joint cross-section was defined and mechanical properties of a welded joint in static tensile test (Re, Rm, A5, Z) were determined. Microstructure and microfractographic tests of fractures were performed.

10

Ferrite content measurements in S32101 lean duplex stainless steel and its welded joints

Niagaj J., Mazur Ł.

Archives of Metallurgy and Materials

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2012

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Vol. 57, iss. 3

780-787

EN

Due to their mechanical and plastic properties as well as unique corrosion resistance, two-phase lean duplex steels are increasingly popular in industrial applications e.g. for building waterside fixtures, ships, pipelines or containers. A critical factor of welded joints made of such steels is the balance between austenite and ferrite; the latter being measured by a special device called ferritoscope. The article contains the results of tests focused on measurements of ferrite content in S32101 lean duplex steel and its welded joints. The text also presents the impact of such factors as test sample thickness or shape and condition of measurement surface etc. on test results. In addition, this paper discusses the use of correction factors, describes problems arising during measurements of ferrite in welded joints and presents manners of the elimination of the latter. The conducted tests revealed that MAG method welding parameters affect the content of ferrite in butt welded joints produced with S32101 lean duplex steel.

PL

Dwufazowe stale typu lean duplex z uwagi na ich własności wytrzymałościowe i plastyczne oraz szczególną odporność korozyjną są coraz częściej stosowane w przemyśle do budowy armatury nadbrzeżnej, statków, rurociągów lub zbiorników. W złączach spawanych z tych stali bardzo ważna jest równowaga pomiędzy austenitem i ferrytem. Pomiary zawartości ferrytu wykonuje sie za pomocą np. urządzenia typu ferrytoskop. W artykule przedstawiono wyniki badań zawartości ferrytu za pomocą ferrytoskopu w stali lean duplex S32101 i jej złączach spawanych oraz wpływ na wyniki pomiarów takich czynników jak: grubość mierzonej próbki, stan i kształt powierzchni pomiarowej itp. Omówiono stosowanie współczynników korekcyjnych. Wyszczególniono problemy powstające podczas wykonywania pomiarów ferrytu w złączach spawanych oraz sposoby ich niwelowania. Przeprowadzone badania wykazały, że parametry spawania metodą MAG mają wpływ na zawartość ferrytu w doczołowych złączach spawanych wykonanych ze stali lean duplex S32101.

11

Weldability of pulse GMAW joints of 780 MPa dual-phase steel

So W., Kang M., Kim D.

Archives of Materials Science and Engineering

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2010

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Vol. 41, nr 1

53-60

EN

Purpose: This paper assesses the gap bridgeability of pulse GMAW joints of DP 780 for automobile body. Design/methodology/approach: Wire melting was analyzed using a high-speed camera. The impact of EN ratio on the shape of the bead section was examined after analyzing the macrosection of welding which was obtained on a bead-on-plate-welding experiment. Welding conditions that are robust to the gap were suggested through an analysis on tensile strength, macrosection of the weld and fracture appearance of tensile strength testing at the lap joint welding of DP 780. Findings: A relation among the welding current (welding process parameter of AC pulse GMAW), EN ratio, welding speed and bead shape parameters which include bead width, bead height and penetration were computed. Research limitations/implications: The suitable welding conditions proposed in this paper can change because of types of welding joints thickness of base metal and other reasons. Practical implications: In this study, the suitable welding conditions were presented for securing a good weld quality of DP 780 for the automobile body. Originality/value: Through this study, the correlation between the weld bead geometry and the EN ratio in the AC pulse GMAW was confirmed. Though the weld quality assessment, suitable pulse GMAW conditions of DP 780 were suggested.

12

GMAW process stability evaluation through acoustic emission by time and frequency domain analysis

Huanca Cayo E., Absi Alfaro S. C.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 34, nr 2

157-164

EN

Purpose: In the present work was made the comparative analysis in time domain and frequency domain to the acoustical pressure generate by the electric arc to determinate which of the two analysis methods is better to evaluates the stability in GMAW process. Design/methodology/approach: Welds had been made with the parameters adjusted to get the highest stability. In these conditions, were simulated instabilities that had been generated by the grease presence in the weld trajectory. In both experimental groups was acquired the acoustical pressure signal produced by electric arc to made analysis based in time domain and frequency domain. Findings: After this comparative study we conclude that the acoustical evaluation of the stability on the GMAW process presents more clarity for the analysis based in the time domain that the frequency domain. Research limitations/implications: In the gotten results, the time domain analysis method could represent adequately the stability and the instability of the process. The stability characterizes for the continuity and minim variation of the statistical parameters, but in the presence of instabilities, these parameters present chaotic changes. In the frequency domain method the variations are imperceptible for steady and unstable regions, but it presents little definite variations in the amplitude of determined bands of frequencies. Originality/value: The stability evaluation in welding is crucial because it is responsible in the weld quality. The non contact methods as the acoustical method have a potentiality extraordinary to monitoring and detect instabilities in welding. The acoustical sensing has the capacity to make an on-line monitoring of the weld process.

13

Weld transference modes identification through sound pressure level in GMAW process

Cayo E. H., Absi Alfaro S. C.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 29, nr 1

57-62

EN

Purpose: One of the most used processes in the industry is GMAW, in this welding process there is physical phenomena such as the temperature, electromagnetic field, luminosity and sound pressure. It is known that GMAW weld specialized techinicisian combine visual and sound at the work to garantee the process stability. It is important to improve the final weld quality; therefore, the quantification of electrical and acoustical behaviour-within the audible bands, offer an information that is important to comprehend his impirical rules. Design/methodology/approach: With these he can identify the transfer mode, instabilities in the process, determine defects and evaluate the weld quality along the weld bead. The sound signal is captured simultaneously with the arc voltage and current signals. Was proved that first derived from the instantaneous power of the electrical arc presents a behaviour similar to the acoustical with a delay, because the measured sound is airborne. Findings: This relation was corroborated by the comparison between the sound pressure level calculated by electrical signals and by acoustical signals. This relation presented a similarity between the calculated signals greater than that between the sound and the power first derived. Practical implications: Besides that, with the sound pressure level it is possible to identify process instabilities that is not so trivial to realize with the sound pressure signal. In spite of it, the identification of instabilities for the globular and spray tranfer modes displays greater difficulty than that for the short circuit transfer mode. It was shown that the acoustical weld sensing offers information about the behaviour of the tranfer mode and the process stability. Originality/value: The sound quantification would be applied as a control variable for the weld process. Thus, it would be possible to develop similar control strategies as those applied by specialized workers.

14

An investigation of metal transfer process in GMAW

Węglowski M. S., Huang Y., Zhang Y. M.

Engineering Transactions

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2008

|

Vol. 56, iss. 4

345-362

EN

This paper presents the studies of the metal transfer process in gas metal arc welding with mild steel electrode. It aims at mathematic description of the droplet flight trajectory, droplet velocity and acceleration. To this end, the droplet flight trajectory was first fitted using the 3rd order polynomial regression and it was found that the model can be reduced to the 2nd order. The average diameter of a droplet transfer rate of droplets, average velocity and acceleration of a droplet were calculated. The geometric shape factor was estimated. A new metal trai monitoring method which is based on narrow band filter and does not require He-Ne laser, has been used in this study to observe the metal transfer process.

15

The effect of welding fixtures on welding distortions

Vural M., Muzafferoglu H. F., Tapici U. C.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

511-514

EN

Purpose: of this paper is to examine the effect of welding fixture used to prevent the distortions during cooling process utilizing a robot controlled gas metal arc welding method on cooling rate and distortions of welded structures. Design/methodology/approach: Using a specially designed welding fixture for a welded steel structure, six different types of AISI 1020 steel specimens are tested in three different welding speeds and two different cooling conditions either at fixture or without using fixture. Findings: designed fixture is reduced amount of distortions. The preheating effect of previous weld on the next weld has increased distortions on the other side of part. Increase in distortions is directly proportional to the increase in welding speed which affects the weld heat input. Research limitations/implications: the study can be repeated on more complex structures and fixtures. Practical implications: the study has shown that the fixture design has an important effect on cooling rate of the welded parts. Originality/value: most of papers in literature is about fixture design methodology, but this paper is an example of demonstration for a practically applied welding fixture.

16

Gazy osłonowe w spawaniu orbitalnym TIG rur ze stali duplex UNS S31803

Nowacki J., Dąbrowski A., Łukojć A.

Przegląd Spawalnictwa

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2003

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R. 75, nr 1

9-14