Effective Area of Groove Welds

Effective area of groove welds shall be considered as the effective length of the welds times the effective throat thickness. The requirements for groove welds are stated here following AWS : D 1.1 : Structural Welding Code-Steel.

The effective length of groove weld shall be the width of the part joined.

The effective throat thickness of a complete penetration groove weld shall be thickness of the thinner part joined.

The effective throat thickness of a partial-penetration groove weld shall be as shown in Table-1.

Table-1: Effective throat thickness of a partial-penetration groove welds.

Welding Process	Welding Position	Include Angle of Root of Groove	Effective throat Thickness
Shielded Metal Arc Submerged Arc Gas Metal Arc Flux-Cored Arc	All	J or U Unit	Depth of Chamfer
		Bevel or V joint ≥600
		Bevel or V joint <600 ≥450	Depth of Chamfer minus 3 mm.

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The effective throat thickness of a flare groove welds when flush to the surface of bar or 90⁰ bend in a formed section shall be as shown in Table-2. Random sections of a production weld for each welding procedure, or such test sections as may be required by design documents, shall be used to verify that the effective throat is consistently obtained.

Table-2: Effective throat thickness of a Flare groove welds.

Type of Weld	Radius (R) of Bar or Bend	Effective throat Thickness
Flare Bevel Groove	All	5/16 R
Flare V- Groove	All	½ R*
Use 3/8 for Gas Metal Arc Welding (except short circuiting transfer process when R≥12mm.

Limitations

The minimum effective throat thickness of a partial penetration groove weld shall be as shown in Table-3. Minimum effective throat thickness is determined by the thicker of the two parts joined, except that the weld size need not exceed the thickness of the thinnest part joined though a large size is required by calculation. For this exception, particular care shall be taken to provide sufficient pre-heat foe soundness of the weld.

Table-3: Minimum effective throat thickness of a partial-penetration groove welds.

Material Thickness of Thicker part joined, mm	Minimum Effective Throat Thickness,mm
To 6 Inclusive	3
Over 6 to 12	5
Over 12 to 20	6
Over 20 to 40	8
Over 40 to 60	10
Over 60 to 150	12
Over 150	16