Compare DC and AC welding on any four points.

Compare DC and AC welding on any four points.
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1 Answer

Answer :

Points
DC Welding
AC Welding
Supply equipment used 
DC differential Compound Generator, or Rectifier
Welding Transformer
Heating Effect
Uniform
Not Uniform
Temperature Obtain
More
Less
Possibility of Arc Blow
More Possibility
No Possibility
Stability of Arc
D.C Differential compound. Generator has dropping characteristics.
Use of series Reactor
Type of Electrode
Non-Coated Electrode is used
Coated Electrode is compulsory
Voltage Required 
50 to 60 volt 
72 to 100 volt 
Capital Cost
High
Low
Running cost
High
Low
Maintenance cost
High
Low
Stand by losses 
High by 25%
Low
Efficiency
Low, 65% 
High, 85%
Application Carbon Arc Welding
Resistance Welding , Metal Arc Welding
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