Heat Induction for Copper-Tube Welding
01 232
4 1 1
Sathaporn Sittiwong 1 and Prasit Chanmontree 1
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ABSTRACT
Nowadays the copper-tube welding work in industrial factories widely gas in welding. However,
the welder might be endangered from the flame. Moreover it will cause pollution from odor and fume.
Accordingly, the project team had an idea to solve there problems, by using copper-tube welding heat
from induction method. The induction set and circuit were designed in simple circuits, consisting of two
main parts j power circuit and control circuit. For the power circuit, full-bridge inverter is used to
function in switching voltage at high frequency, then feed it as input to the primary coil of transformer,
with the work as resonance. For the control circuit, it consists of generating circuit of pulse width
modulation (PWM) signals by using IC No. TL494 as the signal generator. The driving part uses IC No.
TC4424 to drive the isolated transformer. Moreover, it also consists of the overloaded-current prevention
circuit. From the testing, when this induction heat set was connected to the electrical system and
welding was made with silver electrode as the binder of the copper to be with the 12.7 j mm diameter
with the 10 j seconds time and 1,680 j watt electrical power. The efficiency obtained was 78.63%
Key words: Induction Heat, High Frequency
e-mail address : sathaporns@kmutnb.ac.th
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Department of Electrical Engineering Technology, CIT, King Mongkutts University of Technology North Bangkok.
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2
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