• Title/Summary/Keyword: Resistance welding

Search Result 854, Processing Time 0.03 seconds

Characteristics of Drawing and Concurrent Spot Welding of Overlapped Aluminum Plates with Copper Electrodes Inserted in Heated Dies (가열된 금형에 삽입된 구리전극에 의한 중첩된 알루미늄 합금판재의 드로잉성형 동시 점용접 특성)

  • Kim, T.H.;Jin, I.T.
    • Transactions of Materials Processing
    • /
    • v.26 no.3
    • /
    • pp.174-180
    • /
    • 2017
  • In this study, a new spot welding with electric resistance heated dies is suggested for the spot welding of non-ferrous metal plates for drawing and concurrent spot welding. This welding method involves two heating processes such as heating by conduction of electric resistance heated dies and heating by resistance between contacted surfaces of two plates by welding current induced to copper dies for the fusion of contacted metal. This welding process has welding variables such as current induced in heated and copper dies, the inner diameters of heated dies, and edge shape of the copper dies. Experimental conditions for each current should be established to get successful welding strength. The welding strength could reach to the desired value in industrial fields under the following conditions of contact diameters of heated dies in this case of overlapped aluminum5052 plates with 0.3-mm thickness: inner and outer diameters of 5.0 and 16mm, respectively; diameter of copper dies, 5.0mm; heating current, 6.8kA in heated steel dies; welding current, 8.6 kA in copper dies.

Electric Resistance Double Spot Welding Process of Dissimilar Metal Plates of Steel and Aluminum by Using Heating Dies (가열금형을 사용하는 강철과 알루미늄 이종금속판재의 전기저항 이중스폿용접)

  • Kim, T.H.;Sun, Xiaoguang;Jin, I.T.
    • Transactions of Materials Processing
    • /
    • v.27 no.1
    • /
    • pp.37-47
    • /
    • 2018
  • In this paper, a double spot welding process, utilizing electric resistance heating dies, is suggested for the spot welding of dissimilar metal plates for drawing and concurrent spot welding. This double welding process has two heating methods for the fusion welding at the interfacial zone between steel and aluminum plates, such as heating method by thermal conduction of electric resistance by welding current induced to heating dies, and heating method by electric resistance between contacted surfaces of two plates by welding current induced to copper electrode. This double welding process has welding variables such as each current induced in heating dies and in copper electrode, outer diameters of heating dies, and edge shape of copper electrode. Experiments for current conditions in welding process should be demanded in order to get successful welding strength. It was known that the welding strength could be reached to the value demanded on industry fields under such welding conditions as heating dies of outer ring dia.12mm contacted on steel plate, as heating dies of outer ring dia. 14mm contacted on aluminum plate, and as copper electrode of dia. 6.0mm, and as 3 times continuous heating method by $1^{st}$ current of 11 kA(9cycle), $2^{nd}$ current 11 kA(60cycle), $3^{rd}$ current 7 kA(60cycle) applied in steel heating dies and copper electrodes, flat edge of copper electrode, for double spot welding process of dissimilar metal plates of steel and aluminum of 1.0 mm thickness.

The Evaluation on Welding Qualities by Gun Press Force Patterns in the RSW (Resistance Spot Welding) Process using Servo Gun (서보건을 이용한 저항 점용접 공정에서의 가압력 패턴에 의한 용접품질 평가)

  • 박영제;조형석;박지환
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.252-252
    • /
    • 2000
  • The Resistance Spot Welding (RSW) has been considered as an inherently safe and reliable method far joining metals, and has been widely employed, especially in automobile body assembly shops, as a manufacturing process. In recent years, the requirement for more sophisticated quality control procedures has considerably grown in the mass production industries. The object of the application of servo control to spot welding gun is the improvement of quality control in the spot welding, one of conventional industrial areas. The important factors affecting welding qualities (shear strength, nuggest size, indentation depth) are welding current, welding time, and gun press force. Welding current and welding time are controlled by welding timer. But, the conventional welding guns using compressed air are out of control in changing gun press forces in welding process. In this paper, a servo gun welding system having a AC servo motor and a PC control system is presented. The main object of this paper is to estimate the influence of gun press force changes in the welding process (press time -> welding time -> hold time) to welding qualities, and to evaluate welding qualities in real time, by recognizing the patterns of gun press forces changed in the welding process and comparing with the standard patterns.

  • PDF

Characterization of Primary Dynamic Resistance in Resistance Spot Welding (저항 점 용접의 1차 동저항 특성에 관한 연구)

  • 조용준;이세헌;신현일;배경민
    • Journal of Welding and Joining
    • /
    • v.17 no.2
    • /
    • pp.97-103
    • /
    • 1999
  • The dynamic resistance monitoring in primary circuit is one of the important issues. Because in-process and real time quality assurance of resistance spot weld is needed to increase the product reliability. In this study, new dynamic resistance detecting method is proposed as a practical manner of weld quality assurance using instantaneous current and voltage measured at the primary circuit. and also, various patterns of primary dynamic resistance curve are characterized with the macro photograph and the weldability lobe curve. It is found that the primary dynamic resistance patterns are basically similar to those of the secondary, but there is evident advantage such as no extra devices are needed to obtain the quality information and eventually real time feedback control will be possible.

  • PDF

Resistance Spot Weldability of Ferritic Stainless Steel and Galvanized Steel (페라이트계 스테인리스강 / 용융아연도금강 이종 저항 점용접부의 특성)

  • Kim, Jeong-Kil;Woo, In-Su;Jeong, Bo-Young;Lee, Jong-Bong
    • Journal of Welding and Joining
    • /
    • v.24 no.6
    • /
    • pp.39-43
    • /
    • 2006
  • A ferritic stainless steel, STS430, and a galvanized steel for case and frame of electronic goods are welded by resistance spot welding and resistance projection welding methods. In this study, resistance spot welding has been performed to investigate the weldability of dissimilar materials such as a ferritic stainless steel and a galvanized steel. Tensile load of the spot weld without heat treatment was 196 kN and brittle fracture occurred at interface between STS430 and nugget due to the high hardness, 380 Hv, in nugget. It was found that the hardness of as-welded nugget increased with higher cooling rate during resistance spot welding by comparing with GTA weld of same materials. Heat treatment by applying second current made nugget softened. Tensile load of heat treated weld increased and reached to 303 kN and fracture occurred at base metal, a galvanized steel.

Effect of Coating Layer on Electrode Life for Resistance Spot Welding of Al-Coated Hpf and Zn-Coated Trip Steels (Al 도금 HPF 강판과 전기아연도금 TRIP 강판의 저항 점 용접 시 연속타점 전극의 수명에 미치는 도금층의 영향)

  • Son, Jong Woo;Seo, Jong-Dock;Kim, Dong Cheol;Park, Yeong-Do
    • Corrosion Science and Technology
    • /
    • v.11 no.1
    • /
    • pp.29-36
    • /
    • 2012
  • The resistance spot welding of high strength steel degrades the weldability because of its high strength with rich chemical composition and coating layer to protect from corrosion. During the each resistance welding process the electrodes tip reacts with coating layer, then subsequently deteriorates and shorten electrode life. In this study, the Al-coated HPF (Hot Press Forming) steels and Zn-coated TRIP steels were used to investigate the electrode life for resistance spot welding. Experimental results show that the reactivity of Al-coating on HPF steels to electrode tip surface behaviors different from the conventional Zn-coated high strength steels. The electrode tip diameter and nugget size in electrode life test of Al-coated HPF steels are observed to be constant with respect to weld numbers. For Al-coated HPF steels, the hard aluminum oxide layer being formed during high temperature heat treatment process reduces reactivity with copper electrode during the resistance welding process. Eventually, the electrode life in resistance spot welding of Al-coated HPF steels has the advantage over the galvanized steel sheets.

Evaluation of Resistance Spot Welding Weldability of Aluminum Alloy 5000 Series (SPOT 용접을 이용한 알루미늄계 합금의 용접성 평가)

  • 고준빈;염동빈;최병길;이성구;김엄기
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.11 no.3
    • /
    • pp.8-13
    • /
    • 2002
  • In order to obtain the basic informations for the development of high strength and high weldability aluminum alloy sheets, the experimental study was carried out to evaluate resistance spot welding characteristics and welding parameters (welding current, welding time, electrode force) far the aluminum alloy sheets. The mechanical properties of spot weld of aluminum alloy were evaluated by tensile shear test and by peel test at room temperature and also the welding possible zone was established through variation of current electrode force and welding time.

A Study on the Quality Estimation of Resistance Spot Welding Using Hidden Markov Model (은닉 마르코프 모델을 이용한 저항 점용접 품질 추정에 관한 연구)

  • 김경일;최재성
    • Journal of Welding and Joining
    • /
    • v.20 no.6
    • /
    • pp.45-45
    • /
    • 2002
  • This study is a middle report on the development of intelligent spot welding monitoring technology applicable to the production line. An intelligent algorithm has been developed to predict the quality of welding in real time. We examined whether it is effective or not through the In-Line and the Off-Line tests. The purpose of the present study is to provide a reliable solution which can prevent welding defects in production site. In this study, the process variables, which were monitored in the primary circuit of the welding, are used to estimate the weld quality by Hidden Markov Model(HMM). The primary dynamic resistance patterns are recognized and the quality is estimated in probability method during the welding. We expect that the algorithm proposed in the present study is feasible to the applied in the production sites for the purpose of in-process real time quality monitoring of spot welding.

A Study on the Quality Estimation of Resistance Spot Welding Using Hidden Markov Model (은닉 마르코프 모델을 이용한 저항 점용접 품질 추정에 관한 연구)

  • 김경일;최재성
    • Journal of Welding and Joining
    • /
    • v.20 no.6
    • /
    • pp.769-775
    • /
    • 2002
  • This study is a middle report on the development of intelligent spot welding monitoring technology applicable to the production line. An intelligent algorithm has been developed to predict the quality of welding in real time. We examined whether it is effective or not through the In-Line and the Off-Line tests. The purpose of the present study is to provide a reliable solution which can prevent welding defects in production site. In this study, the process variables, which were monitored in the primary circuit of the welding, are used to estimate the weld quality by Hidden Markov Model(HMM). The primary dynamic resistance patterns are recognized and the quality is estimated in probability method during the welding. We expect that the algorithm proposed in the present study is feasible to the applied in the production sites for the purpose of in-process real time quality monitoring of spot welding.