Welding Joint Design & Welding Symbols
Welding Joint Design & Welding Symbols
Welding Joint Design & Welding Symbols
Welding symbols
Weld strength
Extent of joint penetration
Strength of filler wire / weld metal
Discontinuities in the weld
Weld strength
Weld Penetration
Partially
Penetrated
weld
Weld strength
Weld with
defects
Weld with
poor
contour
Weld strength
Using a filler metal that results in weld metal
with matching strength of base material.
Achieving full penetration of the thickness in
a groove weld and the required design size in
fillet welds
Obtaining a sound, defect free weld joint free
from fusion related discontinuities
Achieving a weld with smooth surface
contours and profiles without geometric
discontinuities
Penetration
SMAW PROCESS
Penetration
SMAW PROCESS
Penetration
P
P
SMAW PROCESS
Penetration
P1
P1
SMAW PROCESS
Penetration
SMAW PROCESS
Penetration
Penetration
HEAT FLOW
Penetration
HEAT FLOW
HEAT FLOW
Penetration
HEAT FLOW
Penetration
Penetration
Edge Preparation
Full penetration is achieved by Providing
Root gap between joint edges
Chamfer at the joint edges to provide
approach / access to the arc
Suitable root face at the edges
Method of achieving
Full Penetration
Penetration
Method of achieving
Full Penetration
Penetration
Method of
achieving Full
Penetration
Method of
achieving Full
Penetration
Penetration
Method of
achieving Full
Penetration
Penetration
Groove Dimensions
Included angle
Root Face
Root Gap
Depends on
The heat input of the process
The diameter of the electrode
The thermal expansion/ contraction of
the material
Use of backing strip if any
Included Angle ()
Depends on
The diameter of the electrode
The position of welding
The thickness of the plates
The type of joint
Thickness
Root Gap 2 mm
12
16
20
12
16
20
SV
790
1340
2050
840
1410
2120
DV
424
704
1062
502
830
1222
Design
Distortion
Free
h1: h2 - 7:3
h1
h1: h2 - 6:4
h2
h1: h2 - 1:1
h1: h2 - 4:6
0
1/2
1 1/2
2
2 1/2
Plate thick in inches
Selection of Process
5
4
CO2
GTAW
SAW
SMAW
GW
PAW
EBW
welding process
Welding Position
Thickness of the section
The thermal properties of the material
The main objective is to achieve the required
penetration with minimum weld metal deposit
S2
s1
1
= 55
G = 1.6 3.15 mm
S = 1.6 - 3.15 mm
1= 10-15
2= 45-50
d2
S
d1
1= 10-15
2= 45-40
1 = 30 40
2 = 20
Groove type
T < 3/4
T - 1/2 to 2
T < 3/4
T - to 2
SV
DV
SB
DB
T - 3/4 to 1.5
T > 1.5
SJ
DJ
T - 3/4 to 1.5
SU
T > 1.5
DU
Convexity
Leg Size
Leg Size
Actual throat
Convex
fillet weld
Effective throat
Theoretical throat
aa
Concavity
Actual throat
Leg Size
Effective throat
Leg Size
Theoretical throat
Double
grooved fillet
weld
0.5 t
60
0.29 t
0.29 t
Single fillet
weld
13 mm
Weld area = 80 mm 2
Single
grooved weld
13 mm
Single
grooved
weld with
reinforcing
fillet
13 mm
45
Weld area = 80 mm 2
Single
grooved
weld with
reinforcing
fillet
13 mm
60
Weld area = 90 mm 2
Relative cost
20
Relative cost
of fillet
10
0.5
1.0
1.5
2.0
Weld
symbol
Arrow line
Identifying
line
Joint
Fillet Weld
Seam Weld
Surfacing
SUPPLEMENTARY SYMBOLS
Weld
Profile
Flat
Peripheral Welds
(All around )
Site welds
Convex
Concave
EXAMPLES OF APPLICATION
Welding on the Arrow Side
DIMENSIONING OF WELDS
Groove welds
Fillet welds
z5
l
a5
DIMENSIONING OF WELDS
Spot
Weld
Plug
Weld
n (e)
Seam
Weld
n (e)
Slot Weld
d
n x l (e)
n x l (e)
lap
corner
edge
Fillet weld
3G
2G
4G
1G
2G
5G
6G
45
4F
5F
Size of Electrodes
Dia. - 0.3, 0.5, 1.0, 1.6, 2.0, 2.4, 3.0, 3.2, 4.0,
4.8, 5.0, 6.4, 8.0 mm
Length - 50, 75, 150, 175, 305, 455, 610 mm
Types of Electrodes and Colour Code
AWS
Classification
EWP
EWCe-2
EWla-1
EWla-1.5
EWla-2
EWTh-1
EWTh-2
EWZr-1
Colour *
Green
Orange
Black
Gold
Blue
Yellow
Red
Brown
Alloying
Element
---Cerium
Lanthanum
Lanthanum
Lanthanum
Thorium
Thorium
Zirconium
Alloying
Oxides
---CeO2
La2O3
La2O3
La2O3
ThO2
ThO2
ZrO2
Weight ( % ) of
Alloying Oxide
---1.8 2. 2
0.8 1. 2
1.3 1. 7
1.8 2. 2
0.8 1. 2
1.7 2. 2
0.15 0.4 0
GTAW Equipment
Power Source
Torch
HF Unit
Gas Cylinder
Tungsten Electrode
SAFETY ACCESSORIES
>> Welding hand screens & helmet
>> Chipping goggles.
>> Apron
>> Jacket
>> Gloves
>> Sleeves
>>
Leggings
>>
Shoes
>>
Cap
E8018-B1H4R
Diff. H2
SUF
CELLULOSE SODIUM
CELLULOSE POTASSIUM
DCEP
AC/DCEP/DCEN
2 TITANIA SODIUM
AC/DCEN
3 TITANIA POTASSIUM
AC/DCEP
4 IRON POWDER TI
AC/DCEN/DCEP
5 LOW HYDROGN Na
DCEP
6 LOW HYDROGEN K
AC/DCEP
AC/DCEP
%Mn
%Ni
Moisture
Resistant
%Cr
A1
%Mo
1/2
B1
B2
1-
B3
2-1/4 1
C1
2-1/2
C2
3-1/4
C3
D1&
D2
%V
1.2 2.00
0.50
0.15
.25 .35
0.30
0.20
0.10
E6010
Electrode
60 Ksi
70
80
90
100
110
120
Welding
position
Coating and
current conditions
COMPOSITION OF FLUX
7. Ionizing Substances
Used for stabilizing the arc
Substances : Chalk, Marble
8.Binding substance
Help the coating to grip firmly around the core wire
Substances: Sodium Silicate, Potassium Silicate
COMPOSITION OF FLUX
4.Iron powder
Gives good operating characteristics
Improves arc stability
Makes the coating electrically conducting
5.Oxidizing Substance
Makes the weld metal flow freely
Oxidizing substance are: iron oxide, Lamitite, Magnetite
6.Reducing Substances
They compensate for manganese Ferro Silicon
Substances: Ferro Manganese, Ferro Silicon, Ferro Titanium
contd
2. Rutile:
Found in sand
Arc stabilizer
Good slag former
3. Ball Clay:
Compound of silica & alumina
Slag former & Gives plasticity in the wet paste
contd
CHARACTERISTICS OF ELECTRODES
Rutile Electrodes:
Electrode:
Cellulose
TYPES OF COVERING
Based on covering
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Rutile electrodes
Basic coated electrodes
Cellulose coated electrode
Iron powder,iron oxide electrodes
Based on application:
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Deslaging