Weld Design Symbols

Welding Symbols

(ISO 2553)

and

Weld Joint Design

ELEMENTARY WELD SYMBOLS

Square Groove Weld

Single V Groove Weld

ELEMENTARY WELD SYMBOLS

Single Bevel Groove Weld

Single V Groove Weld with Broad Root Face

ELEMENTARY WELD SYMBOLS

Single Bevel Groove Weld with Broad Root Face

Single U Groove Weld

ELEMENTARY WELD SYMBOLS

Single J Groove Weld

Backing Weld

ELEMENTARY WELD SYMBOLS

Fillet Weld

Plug / Slot Weld

ELEMENTARY WELD SYMBOLS

Spot Weld

Seam Weld

ELEMENTARY WELD SYMBOLS

Edge Weld

Surfacing

SUPPLEMENTARY SYMBOLS

FlatConvex Concave

Weld Profile

SUPPLEMENTARY SYMBOLS

Toes blended

smoothlyPermanent

Backing Strip

M

Removable

Backing Strip

MR

SUPPLEMENTARY SYMBOLS

Peripheral Welds

SUPPLEMENTARY SYMBOLS

Site welds

SUPPLEMENTARY SYMBOLS

Tail Optional)

Sequence of Information in the Tail

• Process (as per ISO 4063)

• Acceptance Level (as per ISO 5817 or ISO 10042)

• Working Position (as per ISO 6947)

• Filler Materials (as per ISO 544 or ISO 2560 or

ISO 3581)

EXAMPLES OF APPLICATIONMethod of representation

Weld Joint

Arrow

Line

Reference Line (Continuous)

Reference Line (Dashed)

EXAMPLES OF APPLICATION

Welding on the Arrow Side

Arrow Side

Other Side

EXAMPLES OF APPLICATION

Welding on the Other Side

Arrow Side

Other Side

EXAMPLES OF APPLICATIONWelding on the Other Side

Other

Side

Arrow

Side

EXAMPLES OF APPLICATION

Welding on the Arrow Side

Other

Side

Arrow

Side

EXAMPLES OF APPLICATIONWhich is the Other Side in this case?

Side A

Side C

Side B

Side D

EXAMPLES OF APPLICATIONWelding on both Sides

Other Side

Arrow Side

EXAMPLES OF APPLICATIONSymmetric Welding on both Sides

EXAMPLES OF APPLICATIONPointing of Arrows for Bevel and J Joints

OR

EXAMPLES OF APPLICATIONPointing of Arrows for Bevel and J Joints

DIMENSIONING OF WELDSButt Joints

l

s l s

DIMENSIONING OF WELDSFillet Welds

z5 l5

5

a5 l

5

DIMENSIONING OF WELDSFillet Welds

a a a

DIMENSIONING OF WELDSIntermittent Fillet Welds

l (e) l (e)

z n x l (e)

z n x l (e)

DIMENSIONING OF WELDSStaggered Intermittent Fillet Welds

z n x l (e)

z n x l (e)

l (e) l (e)

l (e) l (e)

DIMENSIONING OF WELDSSpot Weld

d n (e)

d

e e

DIMENSIONING OF WELDSSeam Weld

d n x l (e)

d

l e

DIMENSIONING OF WELDSPlug Weld

d n (e)

d

e e

DIMENSIONING OF WELDSSlot Weld

d n x l (e)

d

l e

WELD JOINT DESIGN

Edge Preparation - Need

Poor penetration

Poor strength

Good penetration

Good strength

(100% joint

efficiency)

Edge Preparation

Factors which influence choice of edge preparation

- Thickness

- Material

- Welding process

- Extent of penetration required

- Welding distortion

- Cost

Basic Joint Types

butt

teelap

corner

edge

Basic Weld Types

Groove welds

Fillet weldPlug / slot weld

Spot / seam weld

Applicable Welds for Butt joint

Square Groove weld V Groove weld

U Groove weldBevel Groove weld

J Groove weld

Applicable Welds for Butt joint

Double V Groove weld

Double U Groove weld

Double Bevel Groove weld

Double J Groove weld

Applicable Welds for Tee joint

Applicable Welds for Lap joint

Plug / slot weldSpot / seam weld

Fillet weld

Applicable Welds for Corner Joint

Applicable Welds for Edge Joint

Edge weld

Butt joint

Square Groove weld

Root gap

Butt jointSingle V Groove weld

Groove angle αααα

Root face

Root gap

Weld Reinforcement

Correct

reinforcement

Minimum cost

Good joint

strength

Excess

reinforcement

High cost

Poor joint strength

Under

reinforcement

Poor joint strength

Butt joint – Complete Joint penetration

Weld from face side

Back gouging

Back weld

Butt joint – Complete Joint penetration

Backing weld

Back gouging

Butt joint – Complete Joint penetration

(welding from one side)

TIG / SMAW

welding

Consumable

guide

Butt Joint – Double V groove

Less weld metal

Less distortion

Higher edge preparation cost

Better for thickness > 20 mm

More weld metal

More distortion

Lower edge preparation cost

Better for thickness < 20 mm

Double V groove

Single V groove

Butt Joint – U groove

Good access at the root

Less weld metal

Higher edge preparation cost

Better for thickness > 40 mm

Groove angle

Root face

Root gap

Root radius

Butt Joint – Bevel groove

Double bevel groove

Single bevel grooveBevel angle 40 to 50°

Difficult to approach

the root

Weld defects

Back gouging to

remove root defects

Good weld quality

Butt Joint – J groove

Good access at the root

Back gouging and back welding to get good weld quality

Less weld metal

Higher edge preparation cost

Better for thickness > 40 mm

Tee Joint – Full strength joint

leg

leg throat

throat = 0.707 x leg

leg = 1.414 x throat

In a full strength

joint, leg = 0.75 x

thickness

Tee Joint – Full penetration joint

leg = throat leg = throat

45° or 60°

Tee Joint

Theoretical throat

Actual throat

AWS D 1.1 recommendation when gap > 1.6 mm –

to increase leg size of fillet by the amount of gap

Lap Joint

AWS D 1.1 recommendation

Overlap = 5 x thickness (1 inch minimum)

Gap between mating faces = 1.6 mm max

overlap

Welding Position – Groove

1 G

2 G

3 G

4 G

Welding Position – Groove

1 G 2 G

5 G 6 G

45°

Welding Position – Fillet

1F

2F

3F

4F

Welding Position – Fillet

1F

2F

5F

Welding Positions – Groove

Position Inclination of axis Rotation of face

Flat 0° to 15° 150° to 210°

Horizontal 0° to 15° 80° to 150°

210° to 280°

Overhead 0° to 80° 0° to 80°

280° to 360°

Vertical 15° to 80° 80° to 280°

80° to 90° 0° to 360°

Welding Positions – Fillet

Position Inclination of axis Rotation of face

Flat 0° to 15° 150° to 210°

Horizontal 0° to 15° 125° to 150°

210° to 235°

Overhead 0° to 80° 0° to 125°

235° to 360°

Vertical 15° to 80° 125° to 235°

80° to 90° 0° to 360°