CO₂용접에서 용접 토치의 위치변화와 전압이 용접부에 미치는 영향고찰

김법헌,김원일,이칠순,Kim, Bub-Hun,Kim, Won-Il,Lee, Chil-Soon 한국산업융합학회 2011 한국산업융합학회 논문집 Vol.14 No.2

$CO_2$ Welding which uses $CO_2$ instead of inert gas is most widely used in industrial sites. Welding rod for $CO_2$ Welding is roughly divided into solid wire and flux cored wire. $CO_2$ Welding has higher efficiency than any other welding methods, and also economic and speedy to handle, that's why is used frequently for welding general structures. As most of studies about $CO_2$ Welding are focused on metallurgical changes of successful joints, they developed theories about the change of configuration on weld parts. This study is especially focused on not only the change of configuration on weld parts, but also the change of the penetrating depth through changing the position of welding torch. For inspection, applied AWS A5.20 E70-1 among welding wires and fixed moving angles of torch, but controled the values of voltage and the position of welding. Also Automatic Feed Mechanism is used for exact movement of material, specimen is a piece of steel for general structures. By measuring and analyzing the configuration of sliced section and the values of welding leg length and welding throat after welding, the outcome about the changes turned out.

CO₂용접에서 용접 토치의 위치변화와 전압이 용접부에 미치는 영향고찰

김법헌(Bub-Hun Kim),김원일(Won-Il Kim),이칠순(Chil-Soon Lee) 한국산업융합학회 2011 한국산업융합학회 논문집 Vol.14 No.2

CO₂ Welding which uses CO₂ instead of inert gas is most widely used in industrial sites. Welding rod for CO₂ Welding is roughly divided into solid wire and flux cored wire. CO₂ Welding has higher efficiency than any other welding methods, and also economic and speedy to handle, that's why is used frequently for welding general structures. As most of studies about CO₂ Welding are focused on metallurgical changes of successful joints, they developed theories about the change of configuration on weld parts. This study is especially focused on not only the change of configuration on weld parts, but also the change of the penetrating depth through changing the position of welding torch. For inspection, applied AWS A5.20 E70-1 among welding wires and fixed moving angles of torch, but controled the values of voltage and the position of welding. Also Automatic Feed Mechanism is used for exact movement of material, specimen is a piece of steel for general structures. By measuring and analyzing the configuration of sliced section and the values of welding leg length and welding throat after welding, the outcome about the changes turned out.

CO2로봇용접에서 와이어 돌출 길이에 따른 용입부의 영향고찰

김법헌(Bub-Hun Kim),이칠순(Chil-Soon Lee) 산업기술교육훈련학회 2009 산업기술연구논문지 (JITR) Vol.14 No.3

Steel is the metal that mankind uses industrially and commonly. Especially Carbon Steels are used industrially a lot. Generally people call the metal which has 0.12∼0.20% Carbon content to Mild Steel used for this study, and it is used on steel frame or piping work of boiler. Mild Steel is divided into ferrite, cementite, perrite, ledeburite and austenite steel by its basic structure, and easy to process. We used CO₂Robot Welder and kept regular electric current, pressure, and speed after welding with solid wire and flux cored wire. We measured change of penetration and width of bead according to distance between torch nozzle and the material, also by measuring change of solidity of metal and welded part we supposed to find appropriate welding way to material. We can realize through this study that according to distance between welding torch and the material, electric current, voltage, and speed of welding, depth of penetration and solidity of metal became different, also when the welding torch is approached to the material, it became more stable.

가스성분 및 용접와이어의 변화에 따른 SS400소재의 CO₂용접에서 용접부의 상태변화 고찰

김법헌(Bub-Hun Kim),김원일(Won-Il Kim),최창(Chang Choi),박용환(Yong-Hwan Park) 한국기계가공학회 2012 한국기계가공학회지 Vol.11 No.5

On this study, CO₂ gas, net of Ar gas, and mixed gas in solid wire(AWS ER 70S-6) and flux cored wire(AWS E71T-1) were used to weld on Mild steel(SS400). After the progress, the status changes of the welds in Mild steel(SS400) were investigated with compositional changes. For stable experiments, welding was conducted using the automatic feeder. Radiation testing, hardness testing, chemical composition analysis and penetrated cross-section were measured. Through these experiments, shapes of penetrated cross-section, chemical composition changes, and weld defects according to the variation of welding gas were known. Weld defects and weld cross-sectional shapes by the variation of the welding voltage were also detected.

Duplex Stainless Pipe 溶接部의 特性평가에 관한 硏究

이칠순(Chil-Soon Lee)김법헌(Bub-Hun Kim) 산업기술교육훈련학회 2009 산업기술연구논문지 (JITR) Vol.14 No.1

Stainless Steels are used the place where is required corrosion resistance. But Stainless Steels have some problems by their kinds of structures, their usable range is also limited. Austenite s Stainless Steels have high extensity and flexibility but their strength is low, as for Ferrite s Stainless Steels, they have remarkable corrosion resistance and strength, but their extensity is low. In this study to improve Stainless Steels problems, we examined using Duplex Stainless Steels. Duplex Stainless Steels have excellent resistance about cracks and corrosion by stress, erosion, or fatigue than Austenite Stainless Steels. Although they are more expensive than general carbon steels like 304L and 306L, they can t be high-priced metal judging from their expectancy, security, maintenance cost and cost saving effect for decrease of facility process. As Duplex Stainless Steels are used in the place contains a chloride or chloride mixtures in seawater, they can be said that they are applicable metal in the extremely bad-conditioned circumstance. In this study, our purpose is to grasp the proper welding ways of Duplex Stainless Steels for application to these bad condition

GMAW용접에서 와이어의 돌출길이와 전류 및 전압이 알루미늄 재료에 미치는 영향

백상엽(Sang-Yeob Baek),김법헌(Bub-Hun Kim),이칠순(Chil-Soon Lee) 산업기술교육훈련학회 2010 산업기술연구논문지 (JITR) Vol.15 No.1

As the industrial environment is changed rapidly, organized welding method about nonferrous metals is needed. Taking the advantages of Aluminum that is light and no risk of corrosion, Aluminum has been used for the area of automobile, aircraft, shipbuilding and so forth. Therefore it is unavoidable tendency to weld using Aluminum material. The most important flaw is welding cracks that happen on Aluminum welding. These are high temperature cracks, and they are mainly occurred by segregation of alloyed element in crystal particles or existence of low melting point substance. Blow holes are easier to happen than other metals, Hydrogen is informed as the direct cause of blow holes. Aluminum is easy to be influenced by oxygen of humidity as long as add some heat from outside, so it is difficult to weld and changes its form easily. We welded on this Aluminum material by changing projected length and checked the point to get excellent welding at how much distance. For this study we used pure Aluminum material and Alloy ER 4043 φ1.2 welding rod, also automatic feed mechanism and 500A GMAW machine are used for accurate and stable welding. After welding, we seized internal defects through nondestructive testing and operated hardness test on welding part. After that, we endeavored to look for the conditions by measuring the changes of penetration. Through this study we gained the result about what changes happen on Aluminum material by the difference of projected length, electric current, and voltage in GMAW welding.

STS 436 및 내후성 강에 대한 GMAW 용접에서 경도 변화에 따른 재료의 고온균열 성질변화 고찰 - EN 12072 G 18-8 Mn 용접와이어 사용에 따른 용접부의 변화에 대한 연구(2) -

이칠순(Chil-Soon Lee),김법헌(Bub-Hun Kim) 산업기술교육훈련학회 2012 산업기술연구논문지 (JITR) Vol.17 No.2

In industrial sites trains or vehicles have been used to transport products as a general transportation way. For saving transportation cost it can be the key to produce a storing facility that is lighter, more long-lasting, stronger, and safer as the condition of the same weight. A container doesn t ask high technology to make but allows to carry lots of loads safely. Therefore It s important to achieve automated mass production system. In this study, its purpose is to manufacture a container that is durable and strong against corruption. Thanks to the welding wire diluted on the welding parts, ferritic stainless steel, and components of the weathering steel. To achieve the goal, GMAW welding varied on welding speed, welding wire, and protective gas is applied under the condition that ferritic stainless steel and weathering steel are folded so as to make a durable container compared to a common container. Supposing to know the changes of welded materials through the analyze of components variation after the completion of welding of using EN 12072 G 18-8 Mn welding wire, it s possible to create a better product by applying proper welding condition that can decrease welding defects.

STS 436 및 내후성 강에 대한 GMAW 용접에서 용접속도 변화에 따른 재료의 성질변화 고찰

이칠순(Chil-Soon Lee),김법헌(Bub-Hun Kim) 산업기술교육훈련학회 2011 산업기술연구논문지 (JITR) Vol.16 No.4

In modern industry, carriage or keeping of distribution using transportation such as aircraft, sail, train, vehicle etc, is a common method. In this fierce manufacture site, to build storing facility which is lighter, longer, stronger and safer to carry is the way to economize transport cost. Container is being used most for distribution transport in industrial site. For that, we investigated how to produce containers faster without flaws, which material to choose, what proper welding method and speed are, and which welding wire or protective gas is good for keeping long span. Also examined, how hardness, chemical components and fatigue strength of material change, as welding was proceeded. Through assay of hardness, chemical analysis, and fatigue strength, identified how outer fault of welded part caused welding speed occurs. By attaining flawless welding conditions, this study will help for mass production of containers.

A1100 알루미늄 용접에서 실드가스의 종류에 따른 용입부의 변화 연구

김진수(Jin-Su Kim),김법헌(Bub-Hun Kim),김규태(Gue-Tae Kim),박용환(Yong-Hwan Park) 한국기계가공학회 2013 한국기계가공학회지 Vol.12 No.2

Recently welding of aluminum material is actively carried out to make lightweight in the fields of LNG vessels, aircraft, chemical plants, etc. To obtain high strength, hardness and elongation, elements such as manganese, zinc, silicon, etc should be added in aluminum alloy, which has been improved on the mechanical properties like precipitation hardening, age hardening, loosening, corrosion resistance acid resistance. Ar gas is used as a shielding gas of MIG welding for aluminum, also N₂, O₂, CO₂, H₂ etc can be added depending on the composition of the alloy. In this study, Ar + O², Ar, and He were used for welding, hardness, penetration status and changes in composition of penetrated parts were compared and analyzed. This made it possible to know the status and changes of the process in the penetrated parts depending on used gas throughout this study.