Welding Inspector

The definition here are taken from British Standard (BS) 499-1:1991 "Welding terms and Symbols - Glossary for Welding, Brazing and Thermal Cutting.

1. Welding
A process or operation in which two or more parts are united by means of heat or pressure or both, in such a way that there is a continuity in the nature of the metal between the parts.

2. Brazing
A process of joining generally applied to metals in which, during or after heating, molten filler metal is drawn into or retained in the space between closely adjacent surfaces of the parts to be joined by capillary attraction. In general, the melting point of the filler metal is above 450 C but always below the melting temperature of the parent material.

3. Braze welding
The joining of metals using a technique similar to fusion welding and a filler metal with a lower melting point than the parent metal, but neither using capillary action as in brazing nor intentionally melting the parent metal.

4. Weld
A union of pieces of metal made by welding.

5. Joint
A connection where the individual components, suitably prepared and assembled, are joined by welding or brazing.

6. Type of Joint

• But Join, is a connection between ends or edges of 2 parts making an angle to one another of 135 degree to 180 degree (inclusive in the region of the joint.
  
• T-Join, is a connection between the end or edge of one part and the face of the other part, 5 ~ 90 Degree in the region of the join.
  
• Corner join, a connection between the ends or edges of two parts making an angle to one another of more than 30 degree but less than 135 in the region of the joint
• edge join, a connection between the edges of two parts making an angle to one another of 0~30 degree inclusive in the region of the joint
• cruciform joint, a connection in which two flat plates or two bars are welded to another flat plate at right angles and on the same axis.
  
• lap joint, a connection between two overlapping parts making an angle to one another of 0~5 degree inclusive in the region of the weld or welds.
  

7. Type of Weld

• From Configuration Point of View

*. Butt Weld
*. Fillet Weld
*. Slot weld, a joint between two overlapping components made by depositing a fillet weld
round the periphery of a hole in one component so as to join it to the surface of the other
component exposed through the hole.
*. Plug Weld, A weld made by filling a hole in one component of a workpiece with filler
metal so as to join it to the surface of an overlapping component exposed through
the hole where the hole can be circular or oval.

• From the Penetration Point of View

*. Full Penetration, a welded joint where the weld metal fully pentrates the joint with
complete root fusion. it is also commonly called as Complete Joint Penetration Weld
(CJP).
*. Partial Penetration Weld, a welded join without full penetration, also called as partial
joint penetration weld (PJP)

8. Features of The completed weld

• Parent Metal, is metal to be joined or surfaced by welding.
  
• Filler metal, is metal added during welding.
  
• Weld metal, is all metal melted during the making of a weld and retained in the weld.
  
• Heat affected zone (HAZ), is part of the parent metal that affected (metallurgically) by the heat of welding or thermal cutting but not melted.
  
• Fusion line, is the boundary between the weld metal and HAZ in a fusion weld.
  
• Weld zone, is a zone containing the weld metal and HAZ
• Weld face, is the surface of a fusion weld exposed on the side from which the weld has been made.
  
• Root, is the zone on the side of the first run.
• Toe, is a boundary between a weld face and the parent metal or between runs. This area is a point where high stress concentration occur and often where the initiation points for different type of cracks happen. Toes must blend smoothly in to the parent metal.
  
• Excess weld metal or reinforcement, is a weld metal lying outside the plane joining the toes.