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Weld Joints Of Clad Material
By L D Poyyara
POYYARA CONSULTANTS 2
Clad Material What Is Clad Material / Clad Plate?
Non Corrosive SS / NFS Clad
CS / LAS Base Material
Any ferrous (CS / LAS) base plate which is integrally bonded with a thin sheet / layer of non corrosive (SS / non ferrous) material on one side.
Clad Plate
POYYARA CONSULTANTS 3
Clad Plates Bonding Process
Non Corrosive SS / NFS Clad
CS / LAS Base Material
Clad Bonding by Explosion / Hot Rolling / Fusion Welding.
Clad Plate
POYYARA CONSULTANTS 4
Clad Plates
Non Corrosive SS / NFS Clad CS / LAS Base Material
Base Material: CS / LAS Clad Material:
SS -304, 304 L, 316, 316 L,317, 317 L, 318, 321, 347
NFM / NFA – Copper, Aluminium, Titanium, Monel, Inconel, Cupronickel
Clad Plate
POYYARA CONSULTANTS 5
Clad Plates Where Clad Plates are In Use?
For Fabricating Pressure Vessels & Pipe
Lines which are subjected to high
pressure & corrosion from inside surface
Corrosion Resistant Part 3 to 5 mm thick
Corrosive
Media
Pressure Resistant PartWeld Joint
Clad Restoration
POYYARA CONSULTANTS 6
Clad Plates What is the advantage of using Clad Plates in Pressure Vessel Fabrication?
Saving in Material Cost. Allows to use low cost CS / LAS corrosive base material as pressure retaining pats for highly
corrosive fluid. An inside thin layer of non corrosive clad prevents internal corrosion
Corrosion Resistant Part 2 to 5 mm thick
Corrosive
Media
Pressure Resistant PartWeld Joint
Clad Restoration
POYYARA CONSULTANTS 7
Clad Plates What is the disadvantage of using Clad Plates in Pressure Vessel Fabrication?
Additional Precautions in Fabrication. Cutting, WEP, Rolling, Handling, Set up, Welding, PWHT
Corrosion Resistant Part 2 to 5 mm thick
Weld Joint
Clad Restoration Corrosive
Media
Pressure Resistant Part
POYYARA CONSULTANTS 8
Cladding By Weld Overlay
What is weld Overlay Clad?
One or more layers of corrosion resistant weld metal is deposited on CS / LAS base material
Dilution :- 5 to 8%
ESSC
Final Layer – E 308L First Layer - E309
POYYARA CONSULTANTS 9
Cladding By Weld Overlay Weld Cladding Process: ESSC – Electro Slag Strip Cladding. Applicable to large
inside area of Shell, D/E, Cone, & TS
SASC – Submerged Arc Strip Cladding Applicable to large inside area of Shell, D/E, Cone, TS
FCAW – Flux Cored Arc Welding. Applicable to Flange face, Small size TS, Pipes of smaller diameter,
MIG – Metal Inert Gas Welding. Applicable to Flange face, Small size TS, Pipes of smaller diameter,
SMAW – Shielded Metal Arc Welding. Applicable to small components and repairs of clad
POYYARA CONSULTANTS 10
Cladding By Weld Overlay Typical Section Of Weld Overlay
SASC
Dilution :- 10 to 15%
Final Layer – E 308L
Final Layer – E 308L First Layer - E309
First Layer – E 309
Dilution :- 5 to 8%
ESSC
POYYARA CONSULTANTS 11
Cladding By Weld Overlay
Dilution :- 15 to 20%
FCAW / MIG
Typical Section Of Weld Overlay
SMAW
Dilution :- 20 to 25%
Final Layer
Final Layer First Layer
First Layer
E308L
E309
E308L
E309
POYYARA CONSULTANTS 12
What Is Overlap In Weld Overlay?
The extent of covering or over lapping on previous weld bead by the adjacent bead.
40 to 50 % Over Lap
Less Dilution More Dilution
10 to 15 % Over Lap
More Thickness Less
Thickness
POYYARA CONSULTANTS 13
What Is Significant Of Overlap In Weld Overlay?
Overlap of 40 to 50% in SMAW & FCAW results in Less Dilution & more weld overlay Thickness per layer
Less dilution results weld metal chemistry more towards filler metal chemistry
40 to 50 % Over Lap 10 to 15 % Over Lap
Less Dilution More DilutionMore Thickness
Less Thickness
POYYARA CONSULTANTS 14
Overlap In ESSC & SASC
The extent of covering or over lapping on previous weld bead by the adjacent bead.
4 to 5 mm Over Lap
DilutionMinimum Overlay Thickness
POYYARA CONSULTANTS 15
Weld Joints In Clad Plates
Normally Only Base Metal Thickness Is Considered For Design Calculations
Base Metal to be welded with qualified WPS
NDT (RT, UT, MT, PT) of weld joint on base metal to be cleared prior to clad restoration
Clad to be restored by welding (SMAW, FCAW, SAW, SASC, ESSC) with qualified WPS
Base Metal Joint
Clad Restoration Clad Base Metal
POYYARA CONSULTANTS 16
Typical Butt Weld In Clad Plate
Base Metal Weld Joint
Clad Stripping Clad Base Metal
Base Metal Butt Weld
Final Weld
Base Metal Joint
Clad Base Metal
Clad Restoration – Final Layer
Base Metal Joint
Barrier Layer Clad Base Metal
Clad Restoration – Barrier Layer
1
2
3
POYYARA CONSULTANTS 17
Typical Fillet Weld In Clad Plates
3
2
1
SS 304L Clad
SS 304L Clad
SS 304L Clad
SS 304L Support
SS 304L Support
SS 304L Support
Clad Stripping
CS
CS
CS
E309
E308L
18
Liner Attachment
By L D Poyyara
POYYARA CONSULTANTS 19
What Is Liner Attachment?A thin sheet / Strip / Pipe of corrosion resistant material (SS / non ferrous) is attached on corrosive metal surface by welding along the outer edges.
Unlike clad, Liner is not an integral part of base material
It is a substitute for Clad
CS / LAS Base MaterialVent
Attachment Weld Liner
Liner Attachment
POYYARA CONSULTANTS 20
Advantages
- Easy to attach
- Cheaper than integral clad / weld overlay
Disadvantages
- Less durable compared to integral clad
- More chances for leakage through liner in service
- Frequent repair / replacement of liner in service
- Needs vent holes below each liner
CS / LAS Base MaterialVent
Attachment Weld Liner
Liner Attachment
POYYARA CONSULTANTS 21
Typical Liner Attachment Weld
CS / LAS Base MaterialVent
Attachment Weld Liner
Liner
LinerFinal Layer
1St Fillet 2nd Fillet
1 2
3
22
Qualification Requirements For Weld Joints In Clad Material
By L D Poyyara
POYYARA CONSULTANTS 23
Welding Qualification For Clad Material
Generally Qualifications Separately Done For
1) Weld Joints On Base Material
2) Restoration Of Clad On Weld Joints In Base Metal
Base Metal Weld Joint
Clad Stripping Clad Base Metal
Base Metal Butt Weld
Final Weld
Base Metal Joint
Clad Base Metal
Clad Restoration – Final Layer
1
2
POYYARA CONSULTANTS 24
Welding Qualification For Clad Material
Qualifications For Welding Of Base Material 1) Procedure As Per QW 200 & QW 451 2) Performance As Per QW 300 & 452
Test Coupon May Be With or Without Clad
Base Metal Weld Joint
Clad Stripping Clad Base Metal
Base Metal Weld Joint
OR
POYYARA CONSULTANTS 25
Qualification For Weld Overlay / Clad Restoration
Qualifications For Restoring Clad By Weld Overlay
1) Procedure & Performance As Per QW 217(b), QW 451.4 & QW 453
Test Coupon may be with or without clad
Clad Stripping Clad Base Metal
Base Metal – Without Cladding
Base Metal For Welding Qualification – Weld Overlay / Clad Restoration
OR
Base Metal – With Cladding
POYYARA CONSULTANTS 26
Qualification For Weld Overlay / Clad Restoration
How to qualify procedure?1 Prepare WPS – Format available in ASME Sec. IX
2 Prepare a test coupon of P number in WPS
3 Coupon may be with or without clad
4 Coupon size minimum 150 mm X 150 mm
5 Coupon thickness minimum equal to production weld, maximum need not be more than 25 mm
POYYARA CONSULTANTS 27
Qualification For Weld Overlay / Clad Restoration
Test Coupon For Qualification of Weld Overlay / Clad Restoration
OR
Base Metal – Without Cladding
Clad Stripping Clad
Base Metal – With Cladding
37 mm min
37 mm min
POYYARA CONSULTANTS 28
Qualification For Weld Overlay / Clad Restoration
Welding Of procedure Test Coupon
1. Clean the surface
2. Weld barrier layer as per WPS
3. Width minimum 37 mm and length minimum 150 mm
4. PT examine the barrier layer (optional) – Acceptance as per QW – 195
5. Weld subsequent layers as per WPS
6. PT examine the final layer – Acceptance as per QW – 195
7. Each bead shall have uniform width and height
POYYARA CONSULTANTS 29
Qualification For Weld Overlay / Clad Restoration
Procedure / Performance Qualification Test Coupon
OR
Base Metal – Without Cladding
Clad Stripping Clad
Base Metal – With Cladding
37 mm min
37 mm min Min Job Size – need not > 25 mm
Barrier Layer Final Layer
Weld Area 37 X 150 mm Min
POYYARA CONSULTANTS 30
Procedure Qualification For Weld Overlay / Clad Restoration
Physical Tests , QW – 453
1. Side Bends - Transverse to welding direction - 4 No, WQ – 161
(Location of bend specimens as per QW – 462.5)
Acceptance Standard, QW - 163
1. No open discontinuity more than 1.5 mm in any direction within the weld overlay cladding.
2. No open discontinuity more than 3 mm along the weld interface.
POYYARA CONSULTANTS 31
Procedure Qualification For Weld Overlay / Clad Restoration
Chemical Analysis. QW – 462.5 (a) Requires only when WPS / Spec. Calls for All elements specified in WPS / Spec. are to be
analyzed. Location of chips based on minimum thickness
of clad / overlay envisaged on production welds.
Acceptance Limit Within the WPS / Spec / Clad Chemistry.
POYYARA CONSULTANTS 32
Procedure Qualification For Weld Overlay / Clad Restoration
Location Of Chemical Analysis & Minimum Thickness Qualified
1st 2nd
3rd X
Weld inter Face Base metal
Fusion Face
1st 2nd
3rd
Weld inter Face Base metal
Fusion Face
Location of Chips for Chemical Analysis – Depth Minimum Possible
X X
X = Min. Overlay Thickness Qualified
POYYARA CONSULTANTS 33
Procedure Qualification For Weld Overlay / Clad Restoration
Special Process Essential Variables. QW –251.4 Welding in each position requires separate
qualification
Welding in vertical up hill position qualifies all position ( SMAW, GMAW, GTAW).
Welding with single layer and multilayer needs separate qualification
POYYARA CONSULTANTS 34
Procedure Qualification For Weld Overlay / Clad Restoration
Procedure Qualification Thickness range – Base metal & Overlay
Thickness Of Test Coupon
Base metal thickness Qualified
Weld Overlay Thickness
Min MaxMin Max
Less Than 25 mmTest
Coupon Thickness
AnyMinimum thickness where chemical analysis found within limit
Any
Above 25 mm 25 mm Any
POYYARA CONSULTANTS 35
Performance Qualification For Weld Overlay / Clad Restoration
How to qualify Welders Performance? QW-381
1 Prepare WPS & Qualify the procedure
2 Prepare a test coupon of P number in WPS
3 Coupon may be with or without clad
4 Coupon size minimum 150 mm X 150 mm
5 Coupon thickness minimum equal to production weld, maximum need not be more than 25 mm
POYYARA CONSULTANTS 36
Qualification For Weld Overlay / Clad Restoration
Welding Of Performance Test Coupon
1. Clean the surface
2. Weld barrier layer as per WPS
3. Minimum three beads in first layer
4. Width minimum 37 mm and length minimum 150 mm
5. PT examine the barrier layer (optional) – Acceptance as per QW – 195
6. Weld subsequent layers as per WPS
7. PT examine the final layer – Acceptance as per QW – 195
8. Each bead shall have uniform width and height
POYYARA CONSULTANTS 37
Procedure Qualification For Weld Overlay / Clad Restoration
Physical Tests , QW – 453 Side Bends - Transverse to welding direction - 4
No, WQ – 161
(Location of bend specimens as per QW – 462.5)
Acceptance Standard, QW - 163 No open discontinuity more than 1.5 mm in any
direction within the weld overlay cladding. No open discontinuity more than 3 mm along the
weld interface.
POYYARA CONSULTANTS 38
Applicable Essential variables QW – 350 & 360 No upper limit for thickness of overlay qualified
Welders qualified on Clad restoration or liner attachment are also qualified in weld overlays QW – 381 (d)
No limits in pipe diameters, if welded in longitudinal direction QW – 381 (c)
Performance Qualification For Weld Overlay / Clad Restoration
POYYARA CONSULTANTS 39
Performance Qualification For Weld Overlay / Clad Restoration
Performance Qualification Thickness range – Base metal & Overlay
Thickness Of Test Coupon
Base metal thickness Qualified
Weld Overlay Thickness
Min MaxMin Max
Less Than 25 mmTest
Coupon Thickness
Any
Procedure Qualified
Any
Above 25 mm 25 mm Any
POYYARA CONSULTANTS 40
Qualification Requirements for Liner Attachment
procedure :- WPS qualified on Groove / Fillet as per QW – 202.2 (a), (b) or (c) also qualifies for liner attachments within the essential variables, If chemical analysis is not a requirement
Performance:- Welders those who are qualified for groove / fillet welds as per QW 301 are also qualified for liner attachments within the essential variables
CS / LAS Base MaterialVent
Attachment Weld Liner
Liner Attachment
POYYARA CONSULTANTS 41
Alternate Qualification. QW – 218.2, QW - 383.2 (b) procedure & Performance
- Weld a liner attachment assembly as shown below as per the WPS.
- Base plate thickness min. job size max. need not be more than 25 mm
- One Cross Section from each position for macro exam
- Chemical analysis if required as per WPS only for procedure
- Each position needs separate qualification
- Procedure in vertical up qualifies all position
Liner Attachment
LinerFinal Layer
Thank You