Capacitor Discharge Welding

Percussion WeldingMagnetic Force (AC)

Stud Welding

Stud Welding

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

Learning Activities1. View Slides; 2. Read Notes, 3. Listen to lecture4. Do on-line

workbook

KeywordsStud Welding, Capacitor Discharge, Initial Contact Method, Initial Gap Method, Drawn Arc Method

Variations of Capacitor Discharge Stud Welding

Initial Contact Method

Initial Gap Method

Drawn Arc Method

AWS Welding Handbook

Initial Contact Methodis 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 Methodis 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 Methodis 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

TypicalParameters For the ThreeVariations

AWS Welding Handbook

Peak Welding CurrentsVary from 600 - 20,000 amps

Drawn Arc has lowerpeak current - longer time

AWS Welding Handbook

AWS Welding Handbook

Metals Handbook, ASM, 1983

Metals Handbook, ASM, 1983

Most oftenused, easilymachined

Used for criticalapplications andnonflanged Aluminum

Used for DrawnArc. Slightly pointedto facilitate arc start

Flange

AWS Welding Handbook

Metals Handbook, ASM, 1983

AWS Welding Handbook

Metals Handbook, ASM, 1983Spring Loaded Hand Gun

Metals Handbook, ASM, 1983

Gravity Drop

Metals Handbook, ASM, 1983

With Detergent Spray Without Detergent Spray

Automated Initial Gap Machines often have a detergent spraybetween gap before welding to reduce weld spatter.