Welding terminology

ANSI/AWS A3.0 - 94

Standard Welding Terms and Definitions

Imperative to know the difference between a ‘joint’ and a ‘weld’ and use terms properly

Standard terms must be used when dealing with weld joint and weld geometry to avoid errors in communication

Weld or Joint Geometry & Terms

Butt Corner T-Joint Lap Edge

5 Basic Joint Types

Butt Joint

A Joint between 2 members aligned approximately in the same plane

Butt Joint - Applicable Welds

Bevel-groove Flare-bevel-groove Flare-v-groove J-groove Square-groove

U-groove V-groove Edge-flange

Corner Joint

A Joint between 2 members located approximately at right angles to each other in the form of an L

Corner Joint - Applicable Welds

Fillet Bevel-groove Flare-bevel-groove Flare-v-groove J-groove Square-groove U-groove V-groove

T-Joint

A Joint between 2 members located at approximately right angles to each other in the form of a T

T Joint - Applicable Welds

Fillet Bevel-groove Flare-bevel-groove J-groove Square-groove

Lap Joint

A Joint between 2 overlapping members in parallel planes

Edge Joint

A Joint between the edges of 2 or more parallel, or nearly parallel, members

Joint Nomenclature

Joint root Groove face Root edge Root face Bevel angle Depth of bevel Groove angle

Groove radius Root opening Edge shapes

square single or double bevel single or double J round

Joint Root

The portion of the joint wher the

metals are closest to each other

Groove Face

Root Edge

Root Face

Bevel Angle

Bevel Depth

Groove Angle

Groove Radius

Root Opening

Edge Shapes

Square Single Bevel Double Bevel Single J Double J Flange Round

The above welds may be applied to one side or both sides of the joint, or in combination.

Groove Weld Types

Square Scarf V Bevel

U J Flare-V Flare-bevel

Single Groove Welds

Single SquareSingle BevelSingle VSingle JSingle USingle Flare BevelSingle Flare V

Groove Welds

Double Square Double Bevel Double V Double J Double U Double Flare Bevel Double Flare V

Welding Beads

Stringer bead : made without weaving motion

Weave bead : made with side to side oscillation

Parts Of A Weld

Toe Face Face reinforcement Root reinforcement Root surface Weld Root

Bead Back weld Backing weld Spacer Heat-Affected Zone

(HAZ)

Parts of Welds

Weld Face Weld Toe Face Reinforcement Root Reinforcement Weld Root Back Weld Backing Weld

Parts of Welds

Weld Root Leg, Face, Toe Spacer Weld Metal Heat Affected

Zone

Weld Sizes & Terms

Convex Fillet Leg, size equal Convexity Actual throat Effective throat Theoretical throat

Concave Fillet Leg Size (less than leg length) Concavity Actual, Effective throats

equal Theoretical throat

Convex Fillet Weld

Concave Fillet Weld

Joint & Root Penetration

Term used only in reference to groove welds If only Partial Penetration is intended, it is incorrect to

refer to the weld as Incomplete Joint Penetration

Incomplete Joint Penetration