WELDING TRAININ G PROGRAM
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WELDING TRAININGPROGRAM
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OUTLINEI.COMPANY ORIENTATION
A. IntroductionB. Safety Standard Practices
II. FUNDAMENTALS OF WELDING
A. Introduction to Welding1. Definition of Welding2. Applications of Welding3. Different Types of Welding Processes4. Basic Tools and Equipments
5. Essentials of WeldingB. Types of ElectrodeC. Joint Design and Welding PositionsD. Basic Welding Physics
E. Types of Welding Processes1. SMAW2. GTAW3. FCAW4. SAW
F. Welding Procedure SpecificationG. Welding Defects
1. Causes and Effects2. Prevention and Repair
H. Introduction to Nondestrutctive TestinI. Introduction to Destructive Testing
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FUNDAMENTALS OF WELDING
Welding - the procesresults in joining of through their mtogether by applicatiheat, with or withoapplication of preand with or withoaddition of filler metal
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APPLICATIONS OF WELDING
Structural Weld
Piping
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TYPES OF WELDING
SMAW Shielded Metal Arc WeldingGMAW Gas Metal Arc WeldingFCAW Flux Cored Arc WeldingGTAW Gas Tungsten Arc WeldingPAW Plasma Arc WeldingSAW Submerged Arc WeldingESW Electro Slag WeldingOAW Oxy-Acetylene WeldingSW Stud Welding
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BASIC TOOLS EQUIPMENT
ElectrodesWelding HelmetOther Safety EquipmentHand Tools
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BASIC TOOLS EQUIPMENT
ElectrodesWelding HelmetOther Safety EquipmentHand Tools
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ESSENTIALS OF WELDING
Electrod*Based on metal type
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ESSENTIALS OF WELDING
Electrode Angle&
Travel Speed
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ESSENTIALS OF WELDING
Curre*Based on electrode t
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TYPES OF ELECTRODE
Rutile ElectrodeGives a very stable arc and is easy to strike and re-strike
Cellulose ElectrodeHigh penetrating spray type arc
Basic Low Hydrogen ElectrodeContains a high proportion of basic materials such as limestone and fluorides
Iron Powder ElectrodeExhibits high melting rate, deep penetration and minimum spatter loss
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E-XXXXElectric Arc
WeldingElectrodes
Position
Tensile Strength Coating Characteristic
Example: E-7018Low Hydrogen, Iron Powder
Flat, Horizontal, Vertical, Ov
70,000psi Tensile Strength
S M W ELECTRODE IDENTIFICATION SYSTEM
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EXXT-XElectric Arc Welding Electrodes
Tensile Strength Times 10,000psi
Usability aCa
Indicates an
Position
F W ELECTRODE IDENTIFICATION SYSTEM
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WELDING JOINT GEOMETRY
Jo in t
configuration of members
Weld
union between materials caused by heat, and orpressure
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Fillet BuCompound
WELDING JOINT GEOMETRY
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Edge Spot P
WELDING JOINT GEOMETRY
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WELDING JOINT GEOMETRY
Edge Open & Closed Corner L
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WELDING JOINT GEOMETRY
Tee
Cruciform
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TYPES OF JOINT PENETRATION
Included angle
Root GapRoot Face
Angle ofbevel
Root FaceRoot Gap
Included angle
RootRadius
Single -V Butt Single - U Butt
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TYPES OF JOINT PENETRATION
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SINGLE BUTT WELD PREPARATIONS
Single sided preparations are normally made on thinner materials, or when access from both sides is restri
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DOUBLE BUTT WELD PREPARATIONS
Double sided preparations are normally made on thicker materials, or when access from both sides isunrestricted
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The root gap is used for electrode accessibility to the root of the joint, the smaller the angle of bevelthe larger the root gap is required to achieve good penetration.
BUTT JOINTS
The root gap must be increased as the bevel angle decreases
BUTT JOINTS
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BUTT JOINTS
A double-V butt joint will cut down the amount of welding by one half in comparison to a single-V b
BUTT JOINTS
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BUTT JOINTS
A single-V butt joint is used on thinner materials and where access to one side only is possible e.g. pipe li
A single-V butt joint is also more simpler to prepare
BUTT JOINTS
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Single-V with backing strip/bar
BUTT JOINTS
- A backing strip or backing bar is used mainly to support the root and to prevent burn throughs fromoccurring
- May be used for large root gaps and reduced bevel angles
- It also allows for a feather edge to be used, no root face required
- A backing strip usually forms part of the weld and a backing bar is usually removable
BUTT JOINTS
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BUTT JOINTS
A double-V butt joint cuts down the amount of filler material required
A double-V butt joint reduces the amount of distortion and makes possible alternating the weld passon each side of the joint.
A double-V butt may require the joint to be turned over to complete the other side and access to bothsides is required
BUTT JOINTS
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U and J preparations may also be used to reduce distortion and may also be used as doublepreparations
BUTT JOINTS
„U‟ and „J‟ preparations give a more uniform and even distribution of weld metal throughout the dep
the joint and reduce distortion and residual stresses
On thicker sections the „U‟and „J‟ preparations require less weld metal again reducing distortion
saving welding cost
Main disadvantages of these preparations is that they require costly machining and may suffer from
lack of side wall fusion
TRANSITIONJOINTS
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TRANSITION JOINTS
Transitioning is carried out to reduce the wall thickness on a joint that has two different plate/pipe
thickness to match the thickness of the thinner plate/pipe.
The transition may be applied by a pneumatic beveling machine or by a disc grinder and it is a norma
requirement to have a minimum length four times the thickness of the misalignment or four times the
thickness of the thinnest plate
The transition may be applied to the inside or outside of the joint, in the case of a pipeline it is
normally applied to the inside
TRANSITIONJOINTS
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TRANSITION JOINTS
Abrupt changes in material thickness, causes stress concentrations and low fatigue strength
A smooth transition is required to reduce the chances of fatigue cracking
A taper of less than 1 in 4 is recommended for maximum fatigue strength
TRANSITIONJOINTS
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TRANSITION JOINTS
Joints a) and b) are the most common types of transitioning with c) being used to facilitate testing
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WELDINGPOSITIONS
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WELDING POSITIONS
WELDINGPOSITIONS
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WELDING POSITIONS
BASIC WELDING PHYSICS
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Electric Current (I)
• Flow of electric charge through an electric conductor• Electric charge flows when there is voltage present across a
conductor• Unit: Ampere (A)
BASIC WELDING PHYSICS
BASIC WELDING PHYSICS
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Voltage (V)
• Electrical Potential Difference• Difference in electric potential energy of a unit test charge
transported between two points• Unit: Volts (V)
BASIC WELDING PHYSICS
BASIC WELDING PHYSICS
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BASIC WELDING PHYSICS
Power (P)
• Rate at which energy is transferred, used or transformed• Power = Current X Voltage → P = IV • Unit: AV = watt
BASIC WELDING PHYSICS
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W
Power (P)
• Rate at which energy is transferred, used or transformed• Power = Current X Voltage → P = IV • Unit: AV = watt
BASIC WELDING PHYSICS
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Heat Input (Q)
• Heat supplied by the welding process• Q = k x V x I x 60 where k = thermal efficiency
v x 100 v = travel speed
Process k
SMAW 0.8FCAW 0.8SAW 1.0GTAW 0.6
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WELDING PROCESSES
WELDING PROCESSES
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Welding is regarded as a joining process in which the work pieces are in atomic contact
Solid state processes
Forge weldingFriction welding
Fusion welding processes
MMA (SMAW)
TIG/TAG (GTAW)
FCAW
Sub-arc (SAW)
FUSION WELDING FACTORS
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The four essential factors for fusion welding
1. Fusion is achieved by melting using a high intensity heat source
2. The welding process must be capable of removing any oxide andcontamination from the joint
3. Atmosphere contamination must be avoided
4. The welded joint must possess the mechanical properties required bythe specification being adapted
ARC WELDING SAFETY
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Before continuing with the welding processes section, there are 2 safetyrelated terms that should first be understood.
“Duty Cycle” relates to the current carrying capacity of all conductors,based on a 10 minute cycle i.e. 60% duty cycle means it can carry thespecified current for 6 minutes in 10 then must rest for 4 minutes. A 100%duty cycle has no rest period requirement.
ARC WELDING SAFETY
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Fume or gas Exposure Limit Effect on Health
Cadmium 0.025Mg/m 3 Extremely tox
General Welding Fume 5Mg/m 3 Low toxicit
Iron 5Mg/m 3 Low toxicit
Aluminium 5Mg/m 3 Low toxicit
Ozone 0.20 PPM Extremely toxic
Phosgene 0.02 PPM Extremely toxic
Argon No OEL ValueO 2 air content to be controlled
Very low toxic
OEL/MEL (Occupational or Maximum Exposure Limit) which is used inreference to fume exposure such as that caused in arc welding. The valuemay be in PPM or mg/m 3 depending on a particulate fume, or a gas. Typ
values in EH/40 are
SHIELDED METAL ARC WELDING
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Parent material
Electric Arc
Gas shieldMolten weld pool
Solidified slag
PeBuild up of weld metal
Electrodecovering
Electrode
core wire
• uses a consumable electrode coated in flux tthe weld
• the flux coating disintegrates, giving off spaserve as a shielding gas and providing a layer slag, both of which protect the weld area fromatmospheric contamination
SHIELDED METAL ARC WELDING
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Welding position has a big effect on weld quality.More welder skill is required to weld in the overhead p
(4G), when compared to down hand position (1G)
SHIELDED METAL ARC WELDING
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In the down hand position (1G) the welder can drag the tthe electrode along the joint. In the case of vertical (3overhead welding (4G) the welder always gauges the arc
SHIELDED METAL ARC WELDING
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Current (amps) primarily controls depth of penetration, thigher the current the deeper the penetration. If the current
too high this may lead to high spatter, undercut and thepossibility of burn-through. Arc length is another important consideration in weld quathe arc length is too short the arc will become unstable and
may short circuit. If the arc length is too long, this causes hspatter and incorrect shielding from the atmosphere.
SMAW BASIC EQUIPMENT
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Pow
Hold
Inve
sour
Elect
PoweWelding
visor/filter glass
Return lead
Electrodes
Electrodeoven
Control panel
(amps, volts)
SHIELDED METAL ARC WELDING
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Welder controls
Arc length
Angle of electrode
Speed of travel
SMAW VARIABLE PARAMETERS
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VoltageThe arc voltage in the SMAW process is measured as close to the arc as possible. It isvariable with a change in arc lengthO.C.V.The open circuit voltage is the voltage required to initiate, or re-ignite the electrical arc awill change with the type of electrode being used e.g 70-90 voltsCurrentThe current used will be determined by the choice of electrode, electrode diameter andmaterial type and thickness. Current has the most effect on penetration.
PolarityPolarity is generally determined by operation and electrode type e.g DC +ve or DC -ve
SHIELDED METAL ARC WELDING
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The four electrode covering types used in SMAW weldin
Rutile - general purpose Basic - low hydrogen Cellulose - deep penetration/fusion Iron Powder
SMAW PREPARATION AND CHECKING
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The welding equipment
A visual check should be made on the equipment to ensure that it is in good
working orderThe electrodes
Checking should be made to ensure that the correct specification of electrode is
being used, the electrode has the correct diameter and in good condition. In the
case of basic fluxed electrodes, ensure that the correct heat treatment is being
carried out before use
e.g Baked at 350 ° C, holding 150 ° C, quiver temps 70 ° C
Cellulose and rutile electrodes do not require pre-baking but should be stored i
a dry condition.
SMAW PREPARATION AND CHECKING
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OCV open circuit volts
A check should be made to ensure that the equipment can produce the OCV
required by the consumable and that any voltage selector has been moved to thcorrect position
Current & polarity
A check should be made to ensure that the current type and range is as detailed
on the WPS
Other variables
Checks should be made for correct electrode angle, arc gap and travel speed
Safety
SMAW ADVANTAGES AND DISADVANTAGES
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Advantages Disadvantages
Field or shop use
Range of consumables
All positions
Portable
Simple equipment
High welder skill requir
Low operating factor*
High levels of fume
Hydrogen control (flux
Stop/start problems
* Comparatively uneconomic when compared to some other processesi.e. SAW and FCAW
GAS TUNGSTEN ARC WELDING
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Filler wire
Depositedweld metal
Cap
Switch Han
Shielding gas
Electrode
• uses a non-consumable tungsten electrode toproduce the weld
• the weld area is protected from atmosphericcontamination by an inert shielding gas (argon orhelium), and a filler metal is normally used.
GTAW BASIC EQUIPMENT
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Power
Invertersource
Source panel
Power c
Flow-mTungstenelectrodes
Torch assembly
Return lead
Power controlpanel
GTAW TORCH ASSEMBLY
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Spare ceramicshielding cup
Gas diffuser
Split collet
On/Off switch
Fitted ceramicshielding cup
Tungstenhousing
GTAW VARIABLE PARAMETERS
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VoltageThe voltage of the TIG welding process is variable only by the type of gas being used, andchanges in the arc length
CurrentThe current is adjusted proportionally to the tungsten electrodes diameter being used. Thehigher the current the deeper the penetration and fusion
PolarityThe polarity used for steels is always DC –ve as most of the heat is concentrated at
pole. This is required to keep the tungsten electrode at the cool end of the arc. Whenwelding aluminium and its alloys AC current is used.
GTAW VARIABLE PARAMETERST t l t d
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Tungsten electrodesThe electrode diameter, type and vertex angle are all critical factors considered as essenvariables. The vertex angle is as shown
Vertex angleNote: when welding aluminium with
tungsten end is chamfered and forwhen welding
DC -ve
Note: too fine an angle will promote melting of theelectrodes tip
AC
GTAW TUNGSTEN ELECTRODES
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GTAW VARIABLE PARAMETERS
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Gas type and flow rateGenerally two types of gases are used in TIG welding; argon and helium, though nitromay be considered for welding copper and hydrogen may be added for the welding of
austenitic stainless steels. The gas flow rate is also important .
Argon (Ar) Inert Suitable for welding carbon steel, stainless
steel, aluminium and magnesium
Lower cost, lower flow rates
More suitable for thinner materials andpositional welding
Helium Argon mixes Suitable for welding carbon
stainless steel, copper, alumi
magnesium High cost, high flow rates
More suitable for thicker matmaterials of high thermal co
GTAW PREPARATION AND CHECKING
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The welding equipment
A visual check should be made to ensure the welding equipment is in good
condition
The torch head assembly
Check the diameter and specification of the tungsten electrode, the required
vertex angle and that a gas lens is fitted correctly. Check the electrode stick-ou
length and that the ceramic is the correct type and in good condition
Gas type and flow rateCheck the shielding gas if it is the correct type, or gas mixture and the flow ra
correct for the given joint design, welding position as stated in the WPS
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GTAW ADVANTAGES AND DISADVANTAGES
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Advantages Disadvantages
High quality
Good control
All positions
Low hydrogen
Minimal cleaning
High skill factor re
Small consumable
High protection req
Low productivity
High ozone levels
FLUX-CORED ARC WELDING
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FLUX-CORED ARC WELDING
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• requires a continuously-fedconsumable tubular electrodecontaining a flux and aconstant-voltage/constant-current welding power supply
• an externally suppliedshielding gas is sometimesused, but often the flux itself isrelied upon to generate thenecessary protection from theatmosphere.
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SUBMERGED ARC WELDING
Filler wire spool
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- +
Powersupply
Filler wire spoolFlux hopper
Wire electrode
Flux
Slide rail
• requires a noncontinuousconsumable solid or tubul(flux cored) electrode
• the molten weld and the zone are protected fromatmospheric contaminationbeing “submerged” under
blanket of granular fusibleconsisting of lime, silica,magnesium oxide, calciumfluoride and other compou
SAW BASIC EQUIPMENT
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TransRecti
Power return
cablePower control
panel
Weldcontr
Granulated flux
Granulated flux
We
Electreel
SAW FLUXES
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Fused SAWFluxes Agglomerated SAW F
SAW FLUXES
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Fused Flux
Flaky appearance
Lower weld quality
Low moisture intake
Low dust tendency
Good re-cycling
Very smooth weld profile
Agglomerated Flux
Granulated appearanc
High weld quality
Addition of alloys
Lower consumption
Easy slag removal
Smooth weld profile
SAW ADVANTAGES AND DISADVANTAGES
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Advantages Disadvantages
Low weld-metal cost Easily automated
Low levels of ozone
High productivity
No visible arc light
Minimum cleaning
Restricted welding po
Arc blow on DC curre
Shrinkage defects
Difficult penetration c
Limited joints
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WELDING PROCEDURE SPECIFICATIONS
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WELDING PROCEDURES
Components of a welding procedure
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Parent material• Type (Grouping)• Thickness• Diameter (Pipes)• Surface condition)
Welding process• Type of process (SMAW, FCAW,
TIG, SAW etc)• Equipment parameters• Amps, Volts, Travel speed
Welding Consumables• Type of consumable/diam
consumable• Brand/classification• Heat treatments/ storage
Joint design• Edge preparation• Root gap, root face• Jigging and tacking• Type of baking
Components of a welding procedure
WELDING PROCEDURES
Components of a welding procedure
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Welding Position• Location, shop or site
• W elding position e.g. 1G, 2G, 3G• Any weather precaution
Welding Variables• Run sequences• Back gouging• Interpass temperatures
Thermal heat treatments• Preheat, temps• Post weld heat treatments e.g.
stress relieving
Components of a welding procedure
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Example:Welding ProcedSpecification (W
WELDERS QUALIFICATION
Numerous codes and standards deal with welder qualification e g BS EN 287
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Numerous codes and standards deal with welder qualification, e.g. BS EN 287Once the content of the procedure is approved the next stage is to approve thewelders to the approved procedure. A welders test know as a Weld
Qualif icat ion Test (WQT).
Object of a welder qualification test
To give maximum confidence that the welder meets the requirements of the approvedprocedure (WPS).
The test weld should be carried out on the same material and same conditions as for thesite weldsThe welder who carries out the procedure qualification weld automatically qualify whethe procedure qualifies
WELDERS QUALIFICATION
Information that should be included on a welders test certificate are:
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Information that should be included on a welders test certificate are:
1. Welders name and identification number2. Date of test and expiry date of certificate3. Standard/code e.g. BS EN 2874. Test piece details5. Welding process, welding parameters, amps, volts6. Welding parameters, amps, volts7. Consumables, flux type and filler classification details8. Sketch of run sequence, welding positions9. Joint configuration details10. Material type qualified, pipe diameter etc11. Test results, remarks12. Test location and witnessed by13. Extent (range) of approval
WELDERS QUALIFICATION
Th i ti f ld lifi ti t t
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The inspection of a welders qualification test.
It is normal for a qualified inspectors usually from an independent body to
witness the welding. Under normal circumstances only one test weld per welder is permitted If the welder fails the test weld and the failure is not the fault of the welder e.g
faulty welding equipment then a re-test would be permitted. The testing of the test weld is done in accordance with the applicable code, but
is not normal to carry out tests that measure the mechanical properties of weldse.g. tensile, charpy and hardness tests.
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Example:
Welder Approva
QualificationCertification
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WELD DEFECTS
Defects which may be detected by visual inspection can be grouped und
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y y p g pthe following headings
CracksSolid inclusions
Surface and profiles
Misalignment (set-upirregularities)
Gas pores and porosity
Lack of fusionMechanical damage
Parent material damage
Miscellaneous
Cracks that may occur in welded materials are caused generally by manfactors and may be classified by shape and position Cracks are classed
CRACKS
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Classif ied b y Shape
Longitudinal
Transverse
Branched
Classif ied by Posi t ion
HAZ
Centreline
Crater
Fusion zone
Parent metal
factors and may be classified by shape and position. Cracks are classedas planar.
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MECHANICAL TESTING
MECHANICAL TESTING
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MECHANICAL TESTING
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MECHANICAL TESTING
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Tensile tests
Toughness testing (Charpy, Izod)
Hardness tests
The following mechanical tests have units and are termedquanti tat ive tests
MECHANICAL TESTING
Th f ll i h i l h i d d
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Macro testing
Bend testing
Fillet weld fracture testing
Butt weld nick-break testing
The following mechanical tests have no units and are termedtests
MECHANICAL PROPERTIES
Malleability - Can be deformed a great deal by compression before crack
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Malleability Can be deformed a great deal by compression before crack
Ductile -Can be deformed considerably by tension before it fractures
Toughness -Ability to withstand bending without fracture
Hardness -Measure of the resistance of a material to indentation
BEND TEST
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To determine the soundness of the weld zone. Bend testing can
also be used to give an assessment of weld zone ductility.
There are three ways to perform a bend test
1. Face bend
2. Root bend3. Side bend
BEND TEST
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Weld dressed flush Su
Form
Root bend Face bend
BEND TEST
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Defect indicationGenerally thisspecimen would beunacceptable
Minor ruptension
Acceptance du
requ
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TENSILE TEST
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TENSILE TEST
s t
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A l l - W e l d
M e t a l
T e n s i l e T e s
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IMPACT TEST
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C H A R P Y I M P A C T T E S T
IMPACT TEST
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I Z O D I M P A C T T E S T
IMPACT TEST
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Object of test
T b k h j i h h h ld i i i
FILLET WELD FRACTURE TEST
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1. Specimens are cut to the required length
2. A saw cut approximately 2mm in depth is applied along the fillet welds length
3. Fracture is usually made by striking the specimen with a single hammer blow
4. Visual inspection for defects
To break open the joint through the weld to permit examination othe fracture surfaces
FILLET WELD FRACTURE TEST
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MACRO/MICROSCOPIC EXAMINATION
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Macro/microscopic examinations are used to give a visual evaluatiof a cross-section of a welded joint
Carried out on full thickness specimens
The width of the specimen should include HAZ, weld and parentplate
Will Reveal
MACRO/MICROSCOPIC EXAMINATION
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Weld soundness
Distribution of inclusions
Number of weld passes
Metallurgical structure of weld, fusion zone and HAZ
Location and depth of penetration of weld
Measure the leg length and throat thickness
Macro Micro
MACRO/MICROSCOPIC EXAMINATION
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Visual examination for defects
Cut transversely from the weldGround and polished P400 grit paper
Etched using 10-15% nitric acid solution
Wash and dry
Visual inspection under 5X magnification
Report on results
Visual examination for defects & gra
Cut transversely from the weld
Ground and polished P1200 grit pape
Etched using 1-5% nitric acid solutio
Wash and dry
Visual inspection under 100X-1000X
Report on results
MACRO REPORT
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NON DESTRUCTIVE TESTING
A welding inspector should have a working knowledge of NDT methodsand their applications, advantages and disadvantages.
NON DESTRUCTIVE TESTING
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Magnetic particle inspection (MT)
Dye penetrant inspection (PT)
Radiographic inspection (RT)
Ultrasonic inspection (UT)
Four basic NDT methods
DYE PENETRANT TESTING
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DYE PENETRANT TESTING
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DYE PENETRANT TESTING
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DYE PENETRANT TESTING
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DYE PENETRANT TESTING
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DYE PENETRANT INSPECTION
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Advantages Disadvantages
DYE PENETRANT TESTING
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Simple to useInexpensiveQuick resultsCan be used on any non-porousmaterial
PortabilityLow operator skill required
Surface breaking defect little indication of depthPenetrant may contamincomponentSurface preparation criti
Post cleaning requiredPotentially hazardous ch
MAGNETIC PARTICLE INSPECTION
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Surface and slight sub-surface detection
Relies on magnetization of component being tested
MAGNETIC PARTICLE INSPECTION
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Ferro-magnetic materials only can be tested
A magnetic field is introduced into a specimen being testedMethods of applying a magnetic field, yoke, permanent magnet, prods and flexible cab
Fine particles of iron powder are applied to the test area
Any defect which interrupts the magnetic field, will create a leakage field, which attracparticles
Any defect will show up as either a dark indication or in the case of fluorescent particleunder UV-A light a green/yellow indication
MAGNETIC PARTICLE INSPECTION
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MAGNETIC PARTICLE INSPECTION
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Advantages Disadvantages
MAGNETIC PARTICLE INSPECTION
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Simple to useInexpensive
Rapid results
Little surface preparation required
Possible to inspect through thin
coatings
Surface or slight sub-surfaceonly
Magnetic materials only
No indication of defects dep
Only suitable for linear defe
Detection is required in two
ULTRASONIC INSPECTION TEST
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Surface and sub-surface detection
This detection method uses high frequency sound waves typically above 2
ULTRASONIC INSPECTION TEST
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This detection method uses high frequency sound waves, typically above 2to pass through a material
A probe is used which contains a piezo electric crystal to transmit and receultrasonic pulses and display the signals on a cathode ray tube or digital di
The actual display relates to the time taken for the ultrasonic pulses to travthe distance to the interface and back
An interface could be the back of a plate material or a defect
For ultrasound to enter a material a couplant must be introduced between tprobe and specimen
ULTRASONIC INSPECTION TEST
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The principles of radiography
X or Gamma radiation is imposed upon a test object
RADIOGRAPHIC INSPECTION
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Radiation is transmitted to varying degrees dependant upon the density
of the material through which it is travelling
Thinner areas and materials of a less density show as darker areas on
the radiograph
Thicker areas and materials of a greater density show as lighter areas on
a radiograph
Applicable to metals,non-metals and composites
RADIOGRAPHIC INSPECTION
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RADIOGRAPHIC INSPECTION
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RADIOGRAPHIC INSPECTION
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Permanent recordExpensive consumablesBulky equipment
Advantages Disadvantages
RADIOGRAPHIC INSPECTION
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Little surface preparation
Defect identification
No material type limitation
Not so reliant upon operator skill
Thin materials
y q pHarmful radiationDefect require significantrelation to the radiation bSlow resultsVery little indication of d
Access to both sides requ