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Types of Welding Joints

Welding joints are of generally of two major kinds:

  1. Lap joint or fillet joint
  2. Butt joint
Lap Joint:
The lap joint or the fillet joint is obtained by overlapping the plates and then welding edges of the plates.
Lap joint are of three types: 

  1. Single lap joint
  2. Double lap joint
  3. Parallel fillet joint
Butt Joint:
The butt joint is obtained by placing the plates edge to edge. In butt welds, the plate edges do not require beveling if the thickness of the plate is less than 5mm. On the other hand, if the plate thickness is 5mm to 12.5 mm, the edges should be beveled to V or U-groove on both sides.
Butt joints are of following types: 
  1. Square butt joint
  2. Single V-butt joint
  3. Single U-butt joint
  4. Double V-butt joint
  5. Double U-butt joint
Some other weld joints are as follows: 
  • Corner joint 
  • Edge joint
  • T-joint


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