• Journal of Welding and Joining
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• v.14 no.5
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• pp.87-94
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• 1996

It has been well known in GMA welding process that wire feeding speed (WFS) or deposition rate increases linealy with the increase of wire extension. In this investigation, however, such an well-known relationship was .reconsidered in terms of contact-tube to work distance (CTWD) instead of wire extension. To verify the proposed relationship between WFS and CTWD, bead-on-plate welding was performed with various CTWDs in the range of 15∼35mm under the condition of near-constant voltage and current As expected, the test results showed an excellent linear relation between WFS and CTWD. Furthermore, the value of the slope turned out to be quite similar to those of previous investigators obtained either theoretically or experimentally through the Precise measurement of electrode extension. Present result also demonstred that the increase of CTWD could be very practical measure for increaring deposition rate without any increase of heat input Depending on the tip recess the practical maximum of CTWD was appeared to be limited somewhere in 25∼30mm mainly due to the entrappment of porocity.

• Proceedings of the KWS Conference
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• v.43
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• pp.171-173
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• 2004

Electromagnetic force is one of the most important factor that effect on metal transfer mode, short-circuit rate, spatter generation rate and mechanical properties of weld metal etc. Also, shielding gas and welding current have influence on metal transfer mode in GMAW. In this paper, different ways for external electromagnetic forces are applied by attaching cylindrically rounded conducting wire solenoid on touch tip holding. With the applied electromagnetic field, the arc transfer mode changes from normal mode to rotating mode and spatter generation decreased in electromagnetic fields(N-pole). In MIG welding, the influences of electromagnetic force on the spatter generation showed different tendency as in the $CO_2$ welding. It is possible reasons were discussed.

• Journal of Welding and Joining
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• v.15 no.1
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• pp.55-65
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• 1997

The stress intensity factor has been calculated for the cracked plate subjected to remote normal stress and reinforced with a plate by symmetric spot welding. The solution was based on displacement compatibility condition between the cracked sheet and the reinforcement plate. It is shown that the results from the derived equation for stress intensity factor were agreed with previous solutions. The reinforcement effect gets better as a joining spot is closer to the crack tip and the other joining spots become nearer to the crack surface.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.366-369
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• 1992

In this paper we propose a 3-dimensional formation system using an arc welding robot. The principle of our system is just only to accumulate welding beads, so that the target 3-dimensional surfaces can be built up. Considering the effects of the gravity on the arc welding, the welding torch is steadily clamped and the position and the posture of the target board on which target work is formed is controlled by a 6-axis robot hand. Movements of the target board are controlled considering the 3dimensional shape of the target and the accumulating speed of the welding bead. In order to realize such systems, a distance sensor is mounted on the tip of the robot hand. And a coordinate transformation technique is employed

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.3
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• pp.263-267
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• 2011

Ultrasonic metal welding can be used to weld different metals together safely and precisely, without solder, flux and special preparation. Ultrasonic metal welding machine consists of a power supply, a transducer, a booster and a horn. This paper designed the horn needed for Ultrasonic metal welding. The horn has to be designed and manufactured accurately, because measurements such as the shape, length, mass and etc. have effects on the resonant frequency and the vibration mode. The designed horn has the feature of 40,000Hz of nature frequency, and maximizes vibration range in the Tip by resonance in the frequency of ultrasonic wave machine. In this paper, we calculated and analyzed the natural frequency to find the optimal design of the horn that had the amplitude about $12{\mu}m$ by the modal analysis and harmonic analysis using ANSYS. And we analyzed FFT analysis of the manufactured horn.

• Proceedings of the KWS Conference
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• 2000.10a
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• pp.151-154
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• 2000

• Proceedings of the KWS Conference
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• 1996.05a
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• pp.51-54
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• 1996

• Proceedings of the KWS Conference
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• 1994.05a
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• pp.98-100
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• 1994

• Proceedings of the KWS Conference
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• 1999.05a
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• pp.282-284
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• 1999

• Proceedings of the KWS Conference
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• 2005.06a
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• pp.71-72
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• 2005