Terminology Associated with Fillet and Groove Welds

Convex Fillet Weld

Convex fillet welds have an exterior surface that curves or bumps outward, similar in shape to that of the exterior portion of a circle or sphere.

The throat of the weld should not exceed the required reinforcement or throat thickness maximums.  

The following diagram provides all of the standard terminology associated with a convex fillet weld.

Convex Fillet Weld Terminology Diagram

Concave Fillet Weld

Concave fillet welds have an exterior surface that curves or dips inward, similar in shape to that of the interior portion of a circle or sphere.

The throat of the weld should not be less than the required reinforcement or throat thickness minimums.  

The following diagram provides all of the standard terminology associated with a concave fillet weld.

Concave Fillet Weld Terminology Diagram

Groove Weld

Groove welds are most commonly applied to butt joints and consist of the following types

  1. Square
  2. Single Bevel
  3. Double Bevel
  4. Single V
  5. Double V
  6. Single J
  7. Double J
  8. Single U
  9. Double U

The following diagram provides all of the standard terminology associated with a groove weld.

Groove Weld Terminology Diagram

Basic Joint Types

There are five basic joint types consisting of Butt, Tee, Corner, Edge, and Lap joints. Different weld types such as groove or fillet welds can then be applied to these standard five joint types. 

Welding Basic Joint Types

Fillet Weld Gauges

Fillet Welds are often measured by the use of basic fillet weld gauges. The use of fillet gauges can be a little confusing at first glance, mostly due to the scalloped measuring feature. The basic fillet weld inspection tool has a coped and scalloped feature on the ends of the rectangular tool, each having a specific application. 

The coped portion is used to measure the leg length of fillet welds. The coped portion is elongated on the bottom portion to keep it from interfering with the measurement. This requires that the gauge be positioned twice, once for each leg of the fillet. 

The scalloped portion is used to measure the throat of the weld. The center portion of this side has a short flat feature positioned at 45° degrees, which is designed to come in contact with the weld face. When the flat on the throat side has contact, it is confirmed that the fillet weld meets or exceeds the throat dimension specified on the inspection tool. 


Fillet Weld Gauges

 

Weld Joint Terminology Download PDF


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