Welding Symbol Chart
Basic Welding Symbols and Their Location Significance
Location
Significance
Fillet
Spot or
Projection
Plug or Slot
Stud
Back or
Backing
Seam
Surfacing
Edge
Double-Fillet Welding Symbol
Arrow Side
Fillet Weld Size
Not
Used
Both Sides
No Arrow Side or
Other Side
Significance
Square
Not
Used
V
Groove
U
Bevel
J
Not
Used
Flare-V
Scarf for
Brazed Joint
Flare-Bevel
Included Angle of
Countersink
Plug Weld Size
30°
(Diameter of
Hole at Root)
3/4
Φ1
Pitch (Distance
Between Centers)
of Welds
4
Depth of Filling (Omission
Indicates Filling is Complete
Spot Weld Size
Other Side
.025
RSW
(5)
Weld-All-Around
Not
Used
Not
Used
Supplementary Symbols
Field Weld
Melt-Thru
Not
Used
Not
Used
Not
Used
Not
Used
Location of Elements of a Welding Symbol
Consumable Insert
Groove Angle; Included Angle
of Countersink for Plug Welds
Finishing Symbol
Root Opening; Depth
of Filling for Plug
and Slot Welds
Contour Symbol
Groove Weld Size
Spacer
Basic Joints
Identification of Arrow Side and Other Side Joint
Butt Joint
Arrow of
Welding
Symbol
Corner Joint
Arrow Side
of Joint
Other Side
of Joint
T-Joint
Arrow Side
of Joint
T
Tail (May
Be Omitted
When
Reference
is Not Used)
Other
Side of
Joint
Arrow of
Welding
Symbol
Other Side
of Joint
mplso2.com
{
{
Arrow Side
Member of
Joint
Arrow of Welding Symbol
(N)
Root Opening
Symbol with Backgouging
Where letter designations are to be
included in the tail of the welding
symbol, reference is made to Table 1,
Letter Designations of Welding and
Allied Processes and Their Variations, of
AWS A2.4-98.
Arrow Side of Joint
Arrow of
Welding
Symbol
Other
Side of
Joint
American Welding Society
550 N.W. Lejeune Road
Miami, Florida 33126
3-5
3-5
1/2
1/2
Length of
Segments
OR
6
1/2
(7)
Seam Welding Symbol
Pitch
Groove
Weld Size
Increment
Length
Seam Weld
Size
Pitch
3-9
.030
Number of
Studs
V-Groove Welding Symbol
3/8 (1/2)
1st Operation
2nd Operation
RSEW
Process
Double-Bevel-Groove Welding Symbol
Groove Weld Size
(1)
1/8
60°
Groove Angle
Root
Opening
Flare-V-Groove Welding Symbol
(1-1/4)
Groove Weld Size
Arrow Points Toward
Member to be Beveled
Flare-Bevel-Groove Welding Symbol
Depth of
Bevel
Groove Weld Size
1/4
(1/4)
Backing Weld
Backgouge
Multiple Reference Lines
(1/4)
Groove Weld Size
Complete Joint Penetration
Edge Welding Symbol
Indicates Complete Joint Penetration
Regardless of Type of Weld
or Joint Geometry
1st Operation On Line
Nearest Arrow
2nd Operation
Arrow
Connecting
Reference Line
to Arrow Side
Member of
Joint or Arrow
Side of Joint
Pitch (Distance
Between Centers)
of Segments
Backing Welding Symbol
Stud Welding Symbol
Depth of
Bevel
1/8
CJP
3rd Operation
Flash or Upset Welding Symbol
Melt-Thru Symbol
Process Reference
FW
Joint with Spacer
Edge Weld
Size
Joint with Backing
R
1/32
Root Reinforcement
Letter Designations
Edge Joint
Other Side
Member of
Joint
} L-P
}
Reference
Line
Number of Spot, Seam,
Stud, Plug, Slot, or
Projection Welds
Elements in This Area
Remain As Shown When Tail
and Arrow are Reversed
Weld Symbols Shall Be Contained
Within the Length of the Reference Line
Weld
Symbol
Lap Joint
Arrow Side of Joint
S(E)
Field Weld
Symbol
Weld-AllAround
Symbol
1/8
Groove
Weld Size
Fillet Weld Size
(Length of Leg
OR
Stud Size
(3/16)
Pitch(Center-toCenter Spacing)
of Weld Segments
OTHER
SIDE
Concave
F
A
R
Length of Weld Segment
ARROW
SIDE
Convex
Depth of Bevel;
Size or Strength
for Certain Welds
Specification,
Process, or Other
Reference
BOTH
Flush or Flat
Backing
Contour
SIDES
(Square)
Backing/Spacer (Rectangular)
Not
Used
Staggered Intermittent Fillet Welding Symbol
Backing
Weld
Back
Weld
4
Squae-Groove Welding Symbol
No Arrow Side or
Other Side
Significance
Back Welding Symbol
Number of Welds
Pitch
Process
Both Sides
2-5
2-6
Length of
Segments
2nd Operation
1st Operation
Spot Welding Symbol
Arrow Side
Pitch (Distance
Between Centers)
of Segments
5/16
7/16
Fillet Weld Size
(Length of Leg)
Plug Welding Symbol
Not
Used
Not
Used
Chain Intermittent Fillet Welding Symbol
6
4
Omissions of Length Indicates that
Weld Extends Between Abrupt Changes in
Direction or as Dimensioned
Not
Used
Not
Used
Not
Used
Not
Used
Not
Used
Location
Significance
Not
Used
Not
Used
1/4
3/16
Not
Used
Not
Used
Other Side
Arrow of
Welding
Symbol
Length
Typical Welding Symbols
Flush Contour Symbol
‘R’ Indicates Backing
Removed After Welding
Convex Contour Symbol
With Modified Groove Weld Symbol
Back Weld
G
Double-Bevel Groove
It should be understood that these charts are intended only as shop aids. The only complete and official presentation of the standard welding symbols is in AWS A2.4, Standard Symbols for Welding, Brazing, and Nondestructive Examination.
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