Capacitor Discharge Welding

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Capacitor Discharge Welding Percussion
Welding Magnetic Force (AC) Stud Welding
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Stud Welding

• Learning Activities
• View Slides
• Read Notes,
• Listen to lecture
• Do on-line workbook

• Lesson Objectives
• When you finish this lesson you will understand
• The three methods of stud welding
• Typical Applications of this process

Keywords Stud Welding, Capacitor Discharge,
Initial Contact Method, Initial Gap Method, Drawn
Arc Method
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Variations of Capacitor Discharge Stud Welding
Initial Contact Method
Initial Gap Method
Drawn Arc Method
AWS Welding Handbook
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Initial Contact Method is used only with portable
quipment, principally for welding mild steel
studs. Equipment simplicity makes it ideal for
welding mild steel insulation pins to galvanized
duct work.
Initial Gap Method is used with portable and
fixed equipment for welding mild steel,
stainless steel, and aluminum. Generally, it is
superior to both the drawn arc and initial
contact methods for welding dissimilar metals and
aluminum. Inert gas is not needed for welding
aluminum.
Drawn Arc Method is ideally suited for high speed
production applications involving automatic feed
systems with either portable equipment or fixed
position. Inert gas is required for aluminum.
AWS Welding Handbook
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Typical Parameters For the Three Variations
Peak Welding Currents Vary from 600 - 20,000 amps
Drawn Arc has lower peak current - longer time
AWS Welding Handbook
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AWS Welding Handbook
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AWS Welding Handbook
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Metals Handbook, ASM, 1983
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Flange
Used for Drawn Arc. Slightly pointed to
facilitate arc start
Most often used, easily machined
Used for critical applications and nonflanged
Aluminum
Metals Handbook, ASM, 1983
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AWS Welding Handbook
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Metals Handbook, ASM, 1983
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AWS Welding Handbook
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Spring Loaded Hand Gun
Metals Handbook, ASM, 1983
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Gravity Drop
Metals Handbook, ASM, 1983
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With Detergent Spray
Without Detergent Spray
Automated Initial Gap Machines often have a
detergent spray between gap before welding to
reduce weld spatter.
Metals Handbook, ASM, 1983