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Welding DocumentBY : MANOOSAK RERGPANEE
NDT: ISO 9712,EN 473 PT/MT/RT LEVEL III
ASNT PT/MT/UT/RT LEVEL II
IIW: INTERNATIONAL WELDING ENGINEER (IWE)
EUROPIAN WELDING FEDERATION (EWF)
AWSAmerican Welding Society
Structural Welding Code Steel
มาตรฐานการเช่ือมเหลก็โครงสร้าง
AWS D 1.1 Structural welding (steel)
AWS D 1.2 Structural welding (aluminum)
AWS D 1.3 Structural welding (sheet steel)
AWS D 1.4 Structural welding (reinforcing steel)
AWS D 1.5 Bridge welding
AWS D 1.6 Structural welding (stainless steel)
AWS A2.4Standard symbols for welding, brazing, and non-
destructive examination
AWS A3.0 Standard welding terms and definitions
AWS A5.1Specification for carbon steel electrodes for shielded
metal arc welding
AWS A5.18Specification for carbon steel electrodes and rots for
gas shielded arc welding
AWS B1.10 Guide for the nondestructive examination of welds
AWS B2.1Specification for Welding Procedure and Performance
Qualification
AWS D8.1 Automotive spot welding
AWS D8.6 Automotive spot welding electrodes supplement
AWS D8.7Automotive spot welding recommendations
supplement
AWS D8.8 Automotive arc welding (steel)
AWS D8.9 Automotive spot weld testing
AWS D8.14 Automotive arc welding (aluminum)
AWS D9.1 Sheet metal welding
AWS D10.10 Heating practices for pipe and tube
AWS D10.11 Root pass welding for pipe
AWS D10.12 Pipe welding (mild steel)
Welding Procedures
Producing a welding procedure involves:
Planning the tasks
Collecting the data
Writing a procedure for use of for trial
Making a test welds
Evaluating the results
Approving the procedure
Preparing the documentation
Metallurgical
Welding Procedures
Scope/ITP
Agenda
Criteria
Spect.
Basic of
Welding
Processing
Variable
Procedures
WPS
PQR
WQT
Testing
Tension
Bending
Impact
experience
Code Standard
Variable
Weld ability of the part
a) Suitability for welding:
- chemical composition
- metallurgical properties
- physical properties
b) Welding safety:
- structural design
- state of stresses
c) Possibility for welding:
- preparation for welding
- execution of the welding works- post treatment
• Parent material
• Welding process
• Joint design
• Welding Position
• Welding Variables
• Thermal heat treatments
Welding Variable
Welding Procedures
WPSs: Prequalification Welding Procedure Specification
Before procedure approval.
WPS: Welding Procedure Specification
After procedure approval
PQR: Procedure Qualification Record
Welding procedure test record
• WQT : Welder Qualification Test Record
• After PQR approval
WPS
Welding Procedure Specification
Revision 0 Date Nov 20,2014
By Mr.Sakon P.
Authorized byMr.Manoosak R. Date Nov 20,2014
Type Manual Semi - Automatic
Machine Automatic
IDENTIFICATION WPS No IS-GMAW-001
COMPANY NAME IS
WELDING PROCESS(ES) GMAW
SUPPORTING PQR No.(S) Prequalify
• Type (Grouping)
• Thickness
• Diameter (Pipes)
• Surface condition
Parent material
Welding process
• Type of process - SMAW, - GMAW(MIG/MAG)- GTAW(TIG)- FCAW- SAW …….etc
• Equipment parameters
• Amps, Volts, Travel speed
Welding Process
JOINT DESIGN USED
Type: BUTT WELD
Single Double Weld
Backing : Yes No
Backing Material : ASTM A36
Root Opening - Root Face -
Groove Angle : - Radius(J-U) -
Back Gouging : Yes No Method -
POSITION
Position of Groove: 3G Fillet : -
Vertical Progression : Up Down
Base Matals
Material Spec: ASTM A36
Type or Grade -
Thickness
Groove : 10 mm Fillet -
Diameter (Pipe): -
Joint design
• Edge preparation
• Root gap, root face
• Jigging and tacking
• Type of backing
Welding Joint
Edge Open & Closed Corner Lap
Tee ButtCruciform
Welding Joint
Compound weld
Fillet weldButt weld
Edge weld
Spot weld
Plug weld
4/23/2007
Joint PreparationIncluded angle
Root GapRoot Face
Angle ofbevel
Root FaceRoot Gap
Included angle
Root Radius
Single-V Butt Single-U Butt
Root GapRoot Face Root FaceRoot Gap
Root Radius
Single Bevel Butt Single-J Butt
Angle of bevel Angle of bevel
Land
Joint Preparation
Single Sided Butt Preparations
Single Bevel Single Vee
Single-J Single-U
Single sided preparations are normally made on thinner materials,
or when access form both sides is restricted
Double Sided Butt PreparationsDouble sided preparations are normally made on thicker materials, or when access form both sides is unrestricted
-VeeDouble-BevelDouble
- JDouble - UDouble
4/23/2007
Groove Weld Preparation
bevel angle
root face
root gap
included angle
Typical Dimensions
bevel angle 30 to 35°
root face ~1.5 to~2.5mm
root gap ~2 to ~ 4mm
Figure 3.4 (Continued)-Prequalified CJP Groove Welded Joint Details (see 3.13)
Figure 3.4 (Continued)-Prequalified CJP Groove Welded Joint Details (see 3.13)
POSITION
Position of Groove: 3G Fillet : -
Vertical Progression : Up Down
Welding Position
• Location, shop or site
• Welding position e.g. 1G, 2G, 3G etc.
Welding PositionsPA 1G / 1F Flat / Downhand
PB 2F Horizontal-Vertical
PC 2G Horizontal
PD 4F Horizontal-Vertical (Overhead)
PE 4G Overhead
PF 3G / 5G Vertical-Up
PG 3G / 5G Vertical-Down
H-L045 6G Inclined Pipe (Upwards)
J-L045 6G Inclined Pipe (Downwards)
Butt welds in plate
Flat – 1G Overhead – 4G
Vertical up
3G
Vertical down
3G
Horizontal – 2G
Butt welds in pipe
Flat – 1G
axis: horizontal
pipe: rotated
H-L045-6G
axis: inclined at 45°
pipe: fixed
Horizontal – 2G
axis: vertical
pipe: fixed
Vertical up – 5G
axis: horizontal
pipe: fixed
Vertical down - 5G
axis: horizontal
pipe: fixed
J-L045-6G
axis: inclined at 45°
pipe: fixed
Fillet welds on plate
Flat – 1F Overhead – 4F
Vertical up - 3F Vertical down – 3F
Horizontal – 2F
Fillet welds on pipe
Flat – 1F axis: inclined at 45°
pipe: rotated
Overhead – 4F axis: vertical
pipe: fixed
Vertical up - 5F axis: horizontal
pipe: fixed
Vertical down – 5F axis: horizontal
pipe: fixed
Horizontal – 2F axis: vertical
pipe: fixed
Horizontal – 2FR axis: horizontal
pipe: rotated
PA / 1GPA / 1F
PC / 2GPB / 2F
PD / 4FPE / 4G PG / 3G
PF / 3G
Pipe Welding Positions
Weld: FlatPipe: rotatedAxis: Horizontal
PA / 1G
Weld: Vertical DownwardsPipe: FixedAxis: Horizontal
PG / 5G
Weld: Vertical upwardsPipe: FixedAxis: Horizontal
PF / 5G
Weld: Upwards Pipe: FixedAxis: Inclined
Weld: HorizontalPipe: FixedAxis: Vertical
PC / 2G
45o
Weld: Downwards Pipe: FixedAxis: Inclined
J-LO 45 / 6G
45o
H-LO 45 / 6G
PositionAWS D1.1, Table 4.1, WPS Qualification
CJP Groove Weld (Plate or Tubular)
Position Tested Position Qualified*
1G, 1G (Rotated) F
2G F, H
3G V
4G OH
5G F, V, OH
(2G+5G), 6G, 6GR All
PositionAWS D1.1, Table 4.1, WPS Qualification
Fillet Weld (Plate or Tubular) Qualification Test:
Position Tested Position Qualified
1F, 1F (Rotated) F
2F, 2F (Rotated) F, H
3F V
4F (Plate) OH
4F (Tubular) F, H, OH 5F All
BASE METALS
Material Spec. ASTM A36
Type of Grade -
Thickness: Groove 10 mm. Fillet -
Diameter (Pipe) -
- Data from Mill Certificate- Go to …… AWS D1.1 Table 3.1Prequalified Base Metal-Filler Metal Combinations forMatching Strength
Parent material
Table 3.1 prequalified Base Material –Filler Metal Combinations for Matching Strength
Parent material
FILLER METALS
AWS Specification A 5.18
AWS Classification ER 70 S-6
SHIELDING
Flux - Gas Ar + Co2
CompositionAr84% + Co216%
Electrode-Flux (Class) - Flow Rate10-18 L/min
Gas Cup Size20 mm.
Welding Consumables
• Type /diameter of consumable
• Brand/classification
• Heat treatments/ storage
Welding ConsumablesEach consumable is critical in respect to:
• Size, (diameter and length)
• Classification / Supplier
• Condition
• Treatments e.g. baking / drying
• Handling and storage is critical for consumable control
• Handling and storage of gases is critical for safety
SMAW Welding ConsumablesPlastic foil sealed cardboard box•rutile electrodes
•general purpose basic electrodes
Tin can•cellulosic electrodes
Vacuum sealed pack
•extra low hydrogen electrodes
AWS A5.1 Alloyed Electrodes
Covered Electrode
Tensile Strength (p.s.i)
Welding Position
Flux Covering
E 60 1 3
AWS A5.5 Alloyed Electrodes
Covered Electrode
Tensile Strength (p.s.i)
Welding Position
Flux Covering
Moisture Control
Alloy Content
E 70 1 8 M G
TYPES OF ELECTRODES
(for C, C-Mn Steels)
AWS A5.1
•Cellulosic EXX10
EXX11
•Rutile EXX12
EXX13
•Rutile Heavy Coated EXX24
•Basic EXX15
EXX16
EXX18
MIG/MAG Welding ConsumablesWelding wires:
• carbon and low alloy wires may be copper coated
• stainless steel wires are not coated
•wires must be kept clean and free from oil and dust
•flux cored wires does not require baking or drying
Courtesy of Lincoln Electric Courtesy of ESAB AB
MIG/MAG – shielding gases
Type of material Shielding gas
Carbon steel
Stainless steel
Aluminium
CO2 , Ar+(5-20)%CO2
Ar+2%O2
Ar
MIG/MAG shielding gases
Argon (Ar):
higher density than air; low thermal conductivity the arc has a high energy inner cone; good wetting at the toes; low ionisation potential
Helium (He):
lower density than air; high thermal conductivity uniformly distributed arc energy; parabolic profile; high ionisation potential
Carbon Dioxide (CO2):
cheap; deep penetration profile; cannot support spray transfer; poor wetting; high spatter
Ar Ar-He He CO2
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MIG/MAG shielding gasesGases for Short-Circuiting transfer:
• CO2: carbon steels only: deep penetration; fast welding speed; high spatter levels
• Ar + up to 25% CO2: carbon and low alloy steels: minimum spatter; good wetting and bead contour
• 90% He + 7.5% Ar + 2.5% CO2:stainless steels: minimises undercut; small HAZ
• Ar: Al, Mg, Cu, Ni and their alloys on thin sections
• Ar + He mixtures: Al, Mg, Cu, Ni and their alloys on thicker sections (over 3 mm)
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MIG/MAG shielding gasesGases for spray transfer
• Ar + (5-18)% CO2: carbon steels: minimum spatter; good wetting and bead contour
• Ar + 2% O2: low alloy steels: minimise undercut; provides good toughness
• Ar + 2% O2 or CO2: stainless steels: improved arc stability; provides good fusion
• Ar: Al, Mg, Cu, Ni, Ti and their alloys
• Ar + He mixtures: Al, Cu, Ni and their alloys: hotter arc than pure Ar to offset heat dissipation
• Ar + (25-30)% N2: Cu alloys: greater heat input
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Gas Metal Arc WeldingTypes of Shielding Gas
MAG (Metal Active Gas)
• Active gases used are Oxygen and Carbon Dioxide
• Argon with a small % of active gas is required for all steels (including stainless steels) to ensure a stable arc & good droplet wetting into the weld pool
• Typical active gases are
Ar + 20% CO2 for C-Mn & low alloy steels
Ar + 2% O2 for stainless steels
100% CO2 can be used for C - steels
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MIG/MAG - metal transfer modes
Current/voltage conditions
Current
Voltage
Short-Circuit
Spray
transfer
Globular
transfer
Electrode diameter = 1,2 mm
WFS = 3,2 m/min
Current = 145 A
Voltage = 18-20V
Electrode diameter = 1,2 mm
WFS = 8,3 m/min
Current = 295 A
Voltage = 28V
Current type influence
++
+
++
+
++
+
--
-
--
-
--
-
Electrode capacity
Current type & polarity
Heat balance
Oxide cleaning action
Penetration
DCEN DCEPAC (balanced)
70% at work 30% at electrode
50% at work 50% at electrode
35% at work 65% at electrode
Deep, narrow Medium Shallow, wide
No Yes - every half cycle Yes
Excellent (e.g. 3,2 mm/400A) Good (e.g. 3,2 mm/225A) Poor (e.g. 6,4 mm/120A)
Old types: (Slightly Radioactive)
• Thoriated: DC electrode -ve - steels and most metals
• 1% thoriated + tungsten for higher current values
• 2% thoriated for lower current values
• Zirconiated: AC - aluminum alloys and magnesium
New types: (Not Radioactive)
• Cerium: DC electrode -ve - steels and most metals
• Lanthanum: AC - Aluminum alloys and magnesium
Tungsten Electrodes
AWS A 5.12
AWS A 5.12
Electrode tip for DCEN
Electrode tip prepared for low current welding
Electrode tip prepared for high current welding
Vertex angle
Penetration increase
Increase
Bead width increase
Decrease
2-2
,5 t
ime
s e
lect
rod
e d
iam
ete
r
Electrode tip for AC
Electrode tip groundElectrode tip ground and then
conditioned
Tungsten electrodes
The electrode diameter, type and vertex angle are all critical factors
considered as essential variables. The vertex angle is as shown
Vetex angle
Note: when welding
aluminium with AC current,
the tungsten end is
chamfered and forms a ball
end when welding
DC -ve
Note: too fine an angle will
promote melting of the
electrodes tip
AC
TIG Welding Variables
Shielding gas requirements
Preflow
and
Postflow
(6-10 l/min)
Preflow Postflow
Shielding gas flow
Welding current
Flow rate too low
Flow rate too high
TIG Welding ConsumablesWelding consumables for TIG:
• Filler wires, Shielding gases, tungsten electrodes
(non-consumable).
• Filler wires of different materials composition and
variable diameters available in standard lengths,
with applicable code stamped for identification
• Steel Filler wires of very high quality, with copper
coating to resist corrosion.
• shielding gases mainly Argon and Helium, usually
of highest purity (99.9%).
Welding rods:
•supplied in cardboard/plastic tubes
•must be kept clean and free from oil and dust
•might require degreasing
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Fusible Inserts
Before Welding
Pre-placed filler material
After Welding
Other terms used include:
EB inserts (Electric Boat Company)
Consumable socket rings (CSR)
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Fusible InsertsConsumable inserts:
• used for root runs on pipes
• used in conjunction with TIG welding
• available for carbon steel, Cr-Mo steel, austenitic stainless
steel, nickel and copper-nickel alloys
• different shapes to suit application
Radius
Fusible InsertsApplication of consumable inserts
Shielding gases for TIG weldingArgon
• low cost and greater availability
Helium
• costly and lower availability than Argon
• lighter than air - requires a higher flow rate compared with argon (2-3 times)
Nitrogen
• not an inert gas
• high availability - cheap
• added to argon (up to 5%) - only for back purge for duplex stainless, austenitic stainless steels and copper alloys
• not used for mild steels (age embritlement)
Shielding gases for TIG welding
Hydrogen
• not an inert gas - not used as a primary shielding gas
• increase the heat input - faster travel speed and increased penetration
• better wetting action - improved bead profile
• produce a cleaner weld bead surface
• added to argon (up to 5%) - only for austenitic stainless steels and nickel alloys
• flammable and explosive
Welding Variables
• Run sequences
• Back gouging
• Interpass temperatures
TECHNIQUE
Stringer or Weave Bead Stringer or Weave Bead
Multi-pass or Single Pass(per side) Multi-pass
Number of Electrodes 1
Electrode Spacing
Longitudinal -
Lateral -
Angle -
Contact Tube to Work Distance 15-20 mm.
Peening -
Interpass Cleaning Wire Brush
PREHEAT
Preheat Temp.,Min -
Interpass Temp.,Min - Max -
POST WELD HEAT TREATMENT
Temp -
Time -
Thermal heat treatments
Preheat- Table 3.2 Prequalified Minimum Preheat and
Interpass Temperature
Post weld heat treatments• Chapter 5.8 Stress Relief Heat Treatment pg.196
- Table 5.2 Minimum Holding Time page.208
- Table 5.3 Alternate Stress Relief Heat Treatment
page.208
WELDING PROCEDURE
Pass
or
Layer
Process
Filler Metals CurrentAmps/Wire
Feed SpeedVolts
Travel
Speed
(cm/min)
Joint DetailsClass
Dia
mm.
Type/
Polarity
1 GMAW ER 70 S-6 1.2 DCEP 100-120 18 8
2 GMAW ER 70 S-6 1.2 DCEP 120-160 20 10
3 GMAW ER 70 S-6 1.2 DCEP 120-160 20 10
THE END