Training Course in
CWI - Certified Welding Inspector
Training Course Prepared by
Dr. Eng./ Samir Saad
Deputy General Manager , Cutech Arabia LLC,
KSA
Trainer Profile
Education Certification
Samir Saad
Experience: 14 Years (Oil and Gas)
Skills & Expertise
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Welding and Welding Inspection
Non Destructive Testing
Material Technology
In Service & On-stream Inspection
Corrosion and Management
Asset Integrity Management
• Ph.D. of Welding Engineering Technology
• Postgraduate Diploma in Welding
Technology
• Bachelor of Mechanical Engineering
Professional Certification
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CSWIP 3.2 Senior Welding Inspector
BGAS-CSWIP Painting Inspector Grade- 2
Piping Inspector – API 570
Pressure Vessel Inspector – API 510
Aboveground Storage Tank Inspector – API 653
Risk-Based Inspection professional - API580
Corrosion and Materials Professional -API 571
NDT Level III (MT, PT, UT, RT,VT,ET)
ISO 9001 Lead Auditor
 Increasing Need for Weld Quality/ product quality
 economics,
 safety,
 government regulations,
 global competition, and
 the use of less conservative designs
 Inspector - Primary Responsibility

to Ensure Weld Quality

welding inspector is one of the “front line” individuals who must check to
see if all of the required manufacturing steps have been completed
properly.
 The Welding Inspector Must Have:

Training and Experience

Broad Knowledge and Skills

Certification
 Body of Knowledge

ANSI/AWS A1.1 - Metric Practice Guide for the Welding Industry

ANSI/AWS A2.4 - Standard Symbols for Welding, Brazing, & Nondestructive
Examination

ANSI/AWS A3.0 - Standard Welding Terms & Definitions

ANSI/AWS B1.10 - Guide for the Nondestructive Inspection of Welds

ANSI/AWS B1.11 - Guide for the Visual Inspection of Welds

ANSI/ASC Z49.1 - Safety in Welding, Cutting, & Allied Processes

ANSI/AWS QC1: - Standard for AWS Certification of Welding Inspectors
 A responsible person who:

Determines Weld Quality according to applicable codes and/or
specification

May be an overseer of others (variable skills for any amount or type of
workmanship)

May be an inspection and test specialist (specific task with limited
responsibility)

Or, a combination of the above
 The Welding Inspector
A Person Who Brings “KASH” to the Job.


K-----Knowledge
 Drawings ,Codes, Standards, Specifications & Welding Terms , Welding Processes &
Testing Methods

A-----Attitude
 Fair, Impartial, consistent, committed

S----Skills
 Inspection Experience , Welding Experience & Training in Welding Metallurgy

H-----Habits
 Safe practices, Record keeping , Physical condition & Good vision
 Welding Inspector should possess the following qualities:
1. Professional Attitude

(Fair, Impartial, consistent, committed), use facts,,, Not preconceived ideas
2. Good physical condition

Physically fit to access welding locations, Vision Acuity (Jaeger J2 at 12”) &
color perception
3. Ability to understand and apply docs describing weld req.

(dwgs, codes, standards, specs), pre-job review
4. Inspection Experience

Develop proper attitude, new to be paired with experienced
 Welding Inspector should possess the following qualities:
5. Basic knowledge of welding, processes, DT and NDT

Predict, witness, review and judge
6. Ability to be trained

more training the inspector receives, more valuable he’ll be to the employer
7. Safe work habits
8. Ability to complete and maintain records

understandable, neat, maintained
A. Knowledge and Skills:
(1) prepare reports
(2) communicate effectively orally and written
(3) understand the fundamentals of SMAW, SAW, OFW, RW, GTAW, FCAW, GMAW,
PAW, SW, ESW, and Thermal Spraying, Soldering, Mechanical Cutting, Thermal
Cutting/Gouging, Brazing/Braze Welding
(4) understand the fundamentals of VT, MT, UT, PT, RT, LT, quality procedures and quality
audits/surveillance
(5) understand the fundamentals of welding metallurgy
(6) understand welding symbols and drawings
(7) interpret drawings
B. Standards:
(1) verify base material compliance
(2) verify filler metal compliance
(3) verify filler metal storage/handling compliance
(4) verify inspection records compliance
(5) verify proper documentation compliance
(6) verify base material and filler metal compatibility
(7) certify documented results compliance
(8) verify procedure qualification records compliance
(9) verify welding procedure compliance
(10) verify NDE procedures compliance
C. Procedure Qualification:
(1) verify welding equipment appropriateness
(2) verify edge preparation compliance
(3) verify joint geometry compliance
(4) witness procedure qualification
(5) verify welding procedure qualification compliance
(6) review welding procedures for compliance with code and contract requirements
(7) write welding procedures
D. Performance Qualification :
(1) witness welder performance qualification
(2) verify welder qualification compliance
(3) verify welder qualification records compliance
(4) request welder performance requalification
E. Production
(1) verify welder qualification appropriateness
(2) verify production welding compliance
(3) verify personnel qualifications
F. Inspection
(1) perform visual examinations
(2) verify examination procedure compliance
(3) review examination results compliance
(4) develop visual inspection procedures (before, during, and after welding)
(5) provide NDE inspection planning and scheduling (before, during, and after a project)
(6) review welding inspection reports
(7) verify implementation of nondestructive and destructive evaluation methods
G. Safety
(1) be knowledgeable of applicable safety requirements
H. Quality Assurance
(1) perform audits and surveillance
(2) implement weld inspection quality assurance plans
I. Project Management
(1) review contract requirements
(2) review vendor proposal compliance
J. Training
(1) develop and provide a training program for the AWI
(2) develop visual inspection training
K. Evaluation
(1) evaluate AWIs performance
 Inspection Reports “Rules of etiquette”
 Reports should contain sufficient information regarding how the inspection was performed
so that similar results can be obtained later by someone else.
 Clearly and concisely stated facts
 Well organized reports presenting a total picture
 Logical sequence to reporting
 All supporting forms, reports and data included or referenced
 Completed with ink or printed
 When making corrections, cross out the previous entry and initialed & dated the correction
 Should be signed and dated by the inspector who did the job
 A welding inspector must be ethical primarily in order to
 To maintain integrity and high standards of skills, practice, and conduct in the occupation
of welding inspection
 To Safeguard the Public’s Health and Well-being
 Ethical Requirements for the Welding Inspector
 Ethics simply detail what is considered to be common sense and honesty.
 Integrity
 Inspectors should Live by rules and report to their supervisors whenever some
questionable situation occurs
 Ethical Requirements for the Welding Inspector
 Public Statements
 The welding inspector’s position also carries with it a certain responsibility to
the public.
 While inspectors may be incapable of discovering every problem, it is their
responsibility to report any condition that could result in a safety hazard.
 When performing an inspection, inspectors should only do those jobs for
which they are properly qualified. This reduces the possibility of errors in
judgment.
 Ethical Requirements for the Welding Inspector
 Public Statements
 The welding inspector’s position also carries with it a certain responsibility to the public.
 If the inspector is involved in a dispute regarding the inspection, he may be asked to publicly
express an opinion. If stated, the opinion should be based totally on facts that the inspector
believes to be valid.
 the best way to deal with public statements, however, is simply to avoid them whenever
possible.
 The inspector should not volunteer information just to gain publicity. However, in situations where
a public statement is required, the welding inspector may wish to solicit the advice of a legal
representative before speaking.
 The Welding Inspector as a Communicator
 The Welding Inspector as a Communicator
 Experience Required
 CWI Exam
 A- Fundamentals - 2 hrs.

150 questions closed book – Min. pass 108/150 ( 72% )
 B - Practical - 2 hrs.
 46 questions, measurements, calculations – Min. Pass 34/46( 72% )
 C - Code - 2 hrs.
 60 questions, open book- Min. Pass – 44/60 ( 72% )
 Code Options for CWI Exam
 AWS D1.1
- Structural
 AWS D15.1 - Railroad
AWS D1.5
- Bridge
API 1104
- Pipeline
 ASME Section VIII and ASME Section IX, ASME B31.1, ASME B31.3.
 Exam Success
 Must Pass All Three Parts With:
 72% Minimum for CWI
 60% Minimum for CAWI
Q-1 which of the following is Standard Symbols for Welding, Brazing,
& Nondestructive Examination ?
(A) ANSI/AWS A2.4
(B) ANSI/AWS A3.0
(C) ANSI/ASC Z49.1
(D) ANSI/AWS A1.1
(E) ANSI/AWS QC1
Q-2 which of the following is Standard Welding Terms & Definitions ?
(A) ANSI/AWS A2.4
(B) ANSI/AWS A3.0
(C) ANSI/ASC Z49.1
(D) ANSI/AWS A1.1
(E) ANSI/AWS QC1
Q-3 which of the following is National Standard of Safety in Welding,
Cutting, & Allied Processes?
(A) ANSI/AWS A2.4
(B) ANSI/AWS A3.0
(C) ANSI/ASC Z49.1
(D) ANSI/AWS A1.1
(E) ANSI/AWS QC1
Q-4 which of the following is/are expected function for a CWI ?
(A) Develop welding procedure
(B) Compute allowable stresses
(C) Perform radiographic examinations
(D) Conduct tests for analysis of base material composition
(E) None of the above
Q-5 which of the following is/are expected capabilities of welding
inspector to become a CWI ?
(A) Verify welding procedure qualification compliance
(B) Verify weld stress analysis compliance
(C) Verify welder qualification compliance
(D) All of the above
(E) Only A and C above
Q-6 Which of the following records does not require verification by CWI ?
(A) Welder Qualification
(B) Tacker Qualification
(C) Welding Operator Qualifications
(D Welding Supervisors Qualifications
(E) Procedure qualification
Q-7 which of the following must The welding inspector verify ?
(A) All records are completed by the time hardware is shipped even though they may not have
been completed at the end of the operations.
(B) Record of qualification, certification, fabrication and testing are complete and that they meet
appropriate code and /or specification requirements specified for the job.
(C) All the general points are covered in inspection, since detail is never allowed in such
reports
(D) The hardware was completed, and that the shop promises to complete the records before
shipment.
(E) That the quality manual meets the appropriate quality system national or international
standard for welding such as ISO 9000 or GS 9000.
Q-8 At which of the following documents specifies the required welding
condition for a specific application?
A. Procedure Qualification Record (PQR)
B. Welding Procedure Specification( WPS)
C. Welder qualification test ( WQT)
D. Pre-qualified joint detail (PJD)
E. Fit-up specification(FS).
Q-9 Who is ultimately responsible for technical accuracy of a welding
procedure?
A. The American Welding Society
B. The insurance underwriter
C. The welder
D. OSHA
E. The fabricator, manufacturer or contractor
Q-10 Which of the following constitutes proper record keeping?
a. Always use pencil so corrections can be made later
b. When making corrections, cross out the previous entry and initial the
correction
c. Use sketches and pictures wherever possible
d. All of the above
e. Only B and C above
Q-11 Which of the following is NOT important or essential to good record
keeping?
(A) Clearly and concisely stated facts
(B) A good company policy manual
(C) Well organized reports presenting a total picture
(D) Logical sequence to reporting
(E) All supporting forms, reports and data included or referenced
Q-12 Which of the following are true regarding good inspection records?
(A) they record as much detail as necessary.
(B) they include explanation of repairers.
(C) they state that the work stayed within press prescribed tolerances.
(D) all of the above
(E) only B and C above
Q-13 Why should the CWI keep accurate and up –to- date records and
reports
A. To Keep the Superintendent Informed
B. To Impress the Chief Inspector
C. So That He Can Write Better Procedures
D. To Satisfy Governments Agencies
E. To Assure proof of Compliance with Standards and Specifications
Q-14 What is/are the primary reason(s) for a welding inspector to be
ethical ?
A. insure that the employer receives fair value for inspection fees
B. To maintain integrity and high standards of skills, practice, and conduct in
the occupation of welding inspection
C. Reject Every Weld the First Time in Inspection
D. Safeguard the Public’s Health and Well-being
E. B and D above
Q-15 under the AWS QC1 code of ethics, which of the following is one of
the conditions under which the CWI can publicly express an opinion
on the welding inspection subjects ?
(A) When the CWI strongly feels an opinion is justified.
(B) When founded upon knowledge of the facts in issue.
(C) When he is the most senior CWI.
(D) When he is the consensus of the inspection department.
(E) When requested by a legitimate news organization.
Q-16 if a welding inspector feels he is not qualified to make judgment
acceptability of weldment ,what should he do?
A. Do the best he can and report accordingly
B. Call for assistance from someone who is qualified
C. Wait to make judgment until he had time to get additional training
D. Stop all work until procedures are developed within the inspector’s qualifications
E. Allow work to continue because further welder experience will improve quality
 Safety Training
 A key aspect of safety

Mandated by local occupational safety regulations (e.g., OSHA 29CFR1910.1200)
 Aids accident prevention (Welders and other equipment operators work most
safely when they are properly trained in the subject) .
 Proper training includes Instructions in the safe use of Equipment and
Processes, and safety rules that must be followed
 Personnel need to know and Understand rules and consequences of disobeying
them (Example of welder’s head positioning against fumes)
 Before work begins

users must always read and understand the
manufacturers’ instructions on safe
practices for the materials and equipment,
and the Material Safety Data Sheets
(MSDSs).

Certain AWS specifications call for
precautionary labels on consumables and
equipment.

These labels concerning the safe use of the
products should be read and followed
Typical Warning Label for
Arc Welding Processes and Equipment
 Equipment.
 Welding equipment, machines, cable,
and other apparatus shall be located so
that it does not present a hazard to
personnel.
 Good housekeeping shall be maintained.
 Protective Screens.

Workers or other persons adjacent to the welding areas shall be protected from the
radiant energy and spatter of welding and cutting by noncombustible or flame-resistant
screens or shields, or shall be required to wear eye and face protection, and protective
clothing.
Protective Screening Between Workstations
 Eye and Face Protection.
 Arc Welding and Cutting

Welding Helmets, or headshields (w/ appropriate filter plate or
cover plate) MUST be used by Welders and nearby personnel
(ANSI Pub Z87.1)

Lens shade to be selected according to the radiation intensity
(Lens Shade Selector – Table 2.1)

Number 2 filter plate is recommended for general purpose
protection
 Submerged Arc Welding

During SAW – use tinted safety glasses
 Respiratory Protective Equipment
 When controls such as ventilation fail to reduce air contaminants to
allowable levels or when the implementation of such controls are not
feasible, respiratory protective equipment shall be used to protect
personnel from hazardous concentrations of airborne
contaminants.
 Only approved respiratory protective equipment shall be used.
 Whenever the use of respirators is required, a program to establish the
proper selection and use of respirators shall be implemented.
 Protective Clothing
 Clothing shall be selected to minimize the potential for ignition, burning,
trapping hot sparks, or electric shock.
 Clean clothing
 Woolen is best
 Treated cotton acceptable
 No synthetics!
 Gloves
 All welders and cutters shall wear protective flame-resistant gloves.
 All gloves shall be in good repair, dry, and capable of providing
protection from electric shock by the welding equipment.
 Gloves made of leather, rubber, or other suitable materials are
recommended.
 Source of welding fumes
 The welding process
 The consumables.
 The composition of the base metals.
 The surface coating, such as paint or zinc.
 Position of the Head
 Welders and cutters shall take precautions to avoid breathing the fume
directly.
 Avoiding the fume can be done by positioning of the work, the head,
or by ventilation which captures or directs the fume away from the
face.
 The optimum airflow to keep the welder's head out the plume, The air
should flow laterally across the welder’s work station, rather than
from behind.
 Types of Ventilation
 Natural
 Mechanical
Natural
 fans
 Exhaust hood
 Downdraft tables
Air-ventilated
Mechanical
helmets
 Air-ventilated helmets
Downdraft tables
 Confined Space
 Cutting &welding in confined spaces

Prior use? Must know!
 Toxic chemicals
 Flammable chemicals

Fill with inert gas/water

Vent container

Fire extinguishers nearby

Gas cylinder and welding power sources should be located Outside the Confined
Space
 Secure Cylinders During Use. A suitable cylinder
truck, chain, or steadying device shall be used to
keep cylinders from being knocked over while in use.
 for the purpose of identifying the gas content,
Cylinders shall be legibly marked with either the
chemical or the trade name of the gas.
 Cylinders on which the labeling is missing or illegible
shall not be used. They shall be returned to the
supplier.
 Electric Shock
 Many sources for shock (welding and cutting operations)
 Shock currents > 6 (mA) are considered primary current- harmful
 Steady state currents between 0.5mA (perception threshold) and 6mA – secondary
current
 Most equipment operates between 115 and 575 V (fatalities occur from 80 V)
 Electric Shock Prevented
 Insulation - best guard
 Good connections
 Personnel training
ALL
ACCIDENTS CAN BE
PREVENTED !
Q-1 Which of the following Standards define the requirements for safety
in welding, cutting and allied processes
a. ANSI Z49.1
b. AWS QC1
c. AWS D1.1
d. API 1104
e. None of the above
Q-2 Who is responsible to ensure safety in a company during welding
a. Employer
b. Supervisors
c. Welders
d. Welding Inspectors
e. All of the above
Q-3 how should workers or other persons adjacent to the welding areas
can be protected from the radiant of arc welding?
(A) Wearing sun glasses.
(B) Wearing hardhats
(C) Using filters
(D) Wearing protective clothes
(E) Protective Screens.
Q-4 Which lens shade number is recommended when oxyacetylene
welding 16 gauge steel?
(A) Shade # 4 or 5
(B) The same lens shade as recommended for submerged arc welding
(C) Shade # 6 or 8
(D) Shade # 10 or 12
(E) Shade # 2
Q-5 The welding operator is performing welding by SAW process,
employing a current of 300 Amps. The appropriate eye protective lens is
a. Shade No. 14
b. Shade No. 12
c. Clear safety googols or safety glasses
d. No filter lens, but goggles shall be used
e. None of the above
Q-6 Protective Clothing shall be selected to minimize the potential for
a. ignition, burning, trapping hot sparks, or electric shock.
b. electric shock only.
c. Ignition and burning.
d. trapping hot sparks only .
e. None of the above
Q-7 Gloves used for welding shall be in which of the following
conditions according to ANSI-Z49.1?
(A) Dry.
(B) Flame resistant.
(C) Capable protecting from electrical shocks.
(D) All of the above
(E) Only B and C above
Q-8 which of the following contribute to particulate matter in the
welding fumes ?
(A) The welding process
(B) The consumables.
(C) The composition of the base metals.
(D) The surface coating, such as paint or zinc.
(E) All of the above
Q-9 which of the following The best describes the optimum airflow to
keep the welder's head out the plume?
(A) The air should flow down from the ceiling towards the floor.
(B) The air should flow laterally across the welder’s work station.
(C) The air should flow up from the floor towards the ceiling.
(D) The air should flow down from the ceiling towards the floor.
Q-10 During Cutting or welding in confined spaces, where should gas
cylinder and welding power sources be located?
A. Close to Operator
B. On Wheels
C. In a Pick up Truck
D. Outside the Confined Space
E. In the Immediate Area
Q-11 the maximum recommended safe working pressure for Acetylene
is:
(A) 10 psi
(B) 15 psi
(C) 25 psi
(D) 30 psi
(E) 35 psi
Q-12 Whenever the use of respirator is required , what should be
implemented:
(A) a program to establish proper selection and use of respirators.
(A) An increase in lens shade selection.
(B) Shutdown of plant exhaust systems.
(C) All of the above .
(E) Only B and C above
Chapter 4
Metal Joining
&
Cutting Processes
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 3 Basic ‘Process’ Groups
 Welding
 Brazing
 Cutting
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 Shielded Metal Arc Welding
 is an arc welding process wherein coalescence is produced by heating with an electric
arc between a covered metal electrode and the work.
 Sometimes called “Stick”

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Manual process “The SMAW process is almost totally WELDER dependent”
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 The electrode coating, It Provides:
1. Shielding
 some of the coating decomposes to form a gaseous shield for the molten metal.
2. Deoxidation
 the coating provides a fluxing action to remove impurities and oxygen and other
atmospheric gases.
3. Alloying
 the coating provides additional alloying elements for the weld deposit.
4. Ionizing
 when the flux coating becomes molten it improves electrical characteristics to increase
arc stability.
5. Insulating
 the solidified slag provides an insulating blanket to slow down the weld metal cooling
rate.
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 AWS Shielded Metal Arc Covered Electrode Classification System
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 AWS Shielded Metal Arc Covered Electrode Classification System
 Example
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 Stainless Steel Electrodes
Alloy type
of Stainless Steel
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 Electrode Coating Classification F #:
 F-1 High Deposition Group
 (Exx20, Exx24, Exx27, Exx28)
 F-2 Mild Penetration Group
 (Exx12, Exx13, Exx14)
 F-3 Deep Penetration Group
 (Exx10, Exx11) Cellulosic electrode
 F-4 Low Hydrogen Group
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 (Exx15, Exx16, Exx18)
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 Low Hydrogen Electrodes.
 Types end in a ‘5’, ‘6’, or ‘8’
 Purchase in sealed, metal containers
 Store after opening in heated, vented oven
 Most codes require that low hydrogen
electrodes be held at a minimum oven
temperature of 250°F [120°C] after removal
from their
 Limit atmospheric exposure
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 a low moisture content(less than 0.2%),
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 Stainless Steel Electrodes
 E308, E308L - Weld 304 and 304L
 E316, E316L - Weld 316 and 316L
 E309 - Weld Stainless to Carbon Steel
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 Welding Current Types
 AC
 DCEN- DC Electrode Negative ---(Straight) Polarity
 DCEP – DC Electrode Positive ------(Reverse) Polarity
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 Arc length
 The distance between the tip of electrode and the weld surface
Factors affecting the arc
length are
 the class of electrode,
 joint design,
 metal thickness and
 Current setting
 As arc length increases, voltage goes up; and
 as arc length decreases, voltage goes down.
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 Traditional Welding Power Source

Constant Current Power Source
 Electrode moved closer, Arc V falls, Arc A rises
 Electrode moved away, Arc V rises, Arc A drops
 Arc current directly related to heat input
 Welder controls heat input to work
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 Arc blow
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
welding problems is the result of a distorted magnetic field that deflects the
welding arc

Porosity can also result from the presence arc blow
Distorted Magnetic Fields at Ends
of Welds
Dr. Eng./ Samir Saad
Magnetic Field
101
Around Electric Conductor
 To reduce the effects of arc
blow, several alternatives can
be tried. They include:
1.
2.
3.
4.
5.
6.
1. Change from DC to AC.
2. Hold as short an arc as possible.
3. Reduce welding current
4. Use a back-step technique.
5. Wrap work cable around the workpiece
and pass work current through it
6. Extend the end of the joint by attaching
runoff plates.
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 SMAW Advantages
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 SMAW Limitations
1.
Field or shop use
1.
High welder skill required
2.
Inexpensive power supply
2.
Rate deposition is very low
3.
Very portable
3.
Slag removal
4.
All positions
4.
Electrode storage considerations
5.
Welds most alloys
5.
Arc blow
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 Gas Metal Arc Welding
 An arc welding process that uses an arc between a continuous filler metal electrode and
the weld pool the process is used with shielding from an externally supplied gas
 Sometimes called “MIG” or MAG
 Used as automatic or semiautomatic process
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 Process Principles
 Heat source- electric arc between electrode (wire) and the work
 Shielding- an external gas supply
 Filler metal- fed automatically from a spool or reel
 Flux- not applicable
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 Welding Current Types
 DCEP- normal type of current used
 Shielding Gas
 Inert- ( Argon )a gas that does not combine chemically with the base or filler
material
 Carbon Dioxide- not inert, is the most common gas used on low carbon steel
 75% Argon,25%CO2- is used to produce a smoother bead with less spatter, but
will reduce penetration
 Argon/Oxygen- this mixture with 5% Oxygen as maximum will produce a spray
transfer with no spatter
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 GMAW Modes of Transfer
 Spray
 80 %AR -20 CO2
 High amperage and voltage
 flat and horizontal
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 GMAW Modes of Transfer
Pulsed Arc
 various amperage levels
 spray transfer
 all positions
 transition current
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 GMAW Modes of Transfer
Globular

100 % CO2

higher amperage and voltage

flat and horizontal
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 GMAW Modes of Transfer
 Short-Circuiting
 AR/CO2
 low amperage and voltage
 all positions
 provides the lowest amount of heat
to the workpiece and therefore is
prone to incomplete fusion
 This type of transfer produces a
small, fast-freezing weld pool that is
generally suited for the joining of
thin sections, out-of-position
welding, and filling of large root
openings.
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 GMAW Modes of Transfer
Factors for Transfer Modes
 Shielding gas
 Current level
 Voltage level
 Power supply
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 GMAW Electrode Identification System
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 Low Alloy (Solid) Electrode Classification GMAW, GTAW,
and PAWS
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 Stainless Steel (Solid) Electrode Classification GMAW,
GTAW, and PAWS
Alloy type
of Stainless Steel
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 GMAW Power Source Types and Characteristics
 Constant Voltage- 100% duty cycle with flat volt/amp curve
 Is ‘self-regulating’ (maintains constant arc length)
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 GMAW Advantages
1. Works faster as compared to SMAW due to Continuous filler
metal feed
2. High deposition rates as compared to S.M.A.W.
3. produce welds with deeper penetration
4. No slag formation takes place
5. Clean process
6. Welds most alloys
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 GMAW Limitations
1. Equipment is more complex
2. The equipment are Costly and less portable.
3. GMAW is not suitable for Filed since strong wind may below
away the shield
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 Flux Cored Arc Welding
 An arc welding process that uses an arc between a continuous filler metal electrode and
the weld pool.
 the process is uses with shielding gas from a flux contained within the tubular electrode
with or without additional shielding from an externally supplied gas
Self-shielded FCAW Flux-Cored
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 Flux Cored Arc Welding
 Dual-Shielded Flux Cored Arc Welding
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 FCAW Guns - Gas & Self-shielded
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 Welding Current Types
 DCEN or DCEP depending on type of wire
 Shielding Gas
 Carbon dioxide (CO2) is the most widely used for use in welding steel because

CO2 provides deep penetration and low cost
 Methods of Application
 Manual N/A
 Semiautomatic Most Popular
 Mechanized widely used
 Automatic widely used
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 FCAW Electrode Identification System
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 Low Alloy (tubular) Electrode Classification FCAW
Tubular
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 Stainless Steel (tubular) Electrode Classification FCAW
Alloy type
of Stainless Steel
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 FCAW Power Source Types and Characteristics
 Constant voltage with flat volt amp curve
 Constant speed system with a constant current machine
 The wire feeder is a variable speed system
 100% duty cycle
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 FCAW Advantages
1. High quality welds
2. High deposition rates
3. Deep penetration
4. Relatively high travel speeds
5. Suitable for field work
6. Easily mechanized
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 FCAW Limitations
1. Equipment is more expensive
2. Equipment is more complex
3. Slag needs to be removed
4. Primarily only welds steels
5. Very smoky process
6. Filler metal more expensive
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 Gas Tungsten Arc Welding
 An arc welding process that uses an arc between a tungsten electrode (non-consumable)
and the weld pool .
 the process is used with shielding gas
 T.I.G.-Tungsten Inert Gas
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 Tungsten Electrode Classifications
 Tungsten electrode classifications are based on the chemical composition of the
electrode and also shows the color identification system for the various classes of
tungsten electrodes.
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 GTAW Filler Metals (Consumable)
 selection of a filler metal GTAW application
 a filler metal should match the properties of the base metal in the welded
condition
 GTAW cut lengths
 These filler metals do not produce any slag so there is no need for post-weld
cleaning.
 Cut lengths are available in a range of diameters (from 1/16 to 1/8 inches) and in
industry standard lengths of 36 inches (0.9 m)
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 GTAW Filler Metals (Consumable)
 Low Alloy (Solid) Electrode Classification
 ER70S-2, ER70S-3, etc
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 Stainless Steel (Solid) Electrode Classification GMAW,
GTAW, and PAWS
Alloy type
of Stainless Steel
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 GTAW Power Source Types and Characteristics
 Transformer- AC- constant current
 Rectifier- DC- constant current
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 Welding Current Types
Great for AL
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 GTAW Advantages
1. High quality welds /Good appearance
2. No slag
3. Very little, if any, post-weld cleaning required
4. Autogenous welding (welding without filler metal /Good for thin
materials such as AL)
5. Can be automated
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 GTAW Limitations
1. High skill factor required
2. Low deposition rate / Low productivity
3. Lower productivity
4. Higher initial cost of the equipment
5. Shielding gas expensive
6. Purging gas expensive
 to Prevent Oxidation in the root area during welding stainless steel, titanium
and other corrosion-resistant materials
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 Submerged arc welding
 an arc welding process that uses an arc or arcs between a bare metal electrode or
electrodes.
 The arc and molten metal are shielded by a blanket of granular flux on the workpiece
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 SAW Power Source Types and Characteristics
 Constant Voltage (flat) - most of the power sources
 Constant Current (drooping)
 Wire feeder is a variable speed system
 100% duty cycle
 Welding Current Types
 AC
 DCEN or DCEP depending on type
of wire
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 SAW Electrode Identification System
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 Fluxes for SAW Welding
 The 2 methods of flux manufacture are:
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1)
Fused

Baked at high temperature, glossy, hard and black in
colour, cannot add ferro-manganese, non moisture
absorbent and tends to be of the acidic type
2)
Agglomerated

Baked at a lower temperature, dull, irregularly
shaped, easily crushed can easily add alloying
elements, moisture absorbent and tend to be of the
basic type
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 SAW Advantages
 SAW Limitations
1. High quality weld metal
1. Flat or horizontal fillets only
2. Deep penetration
2. Extensive setup time
3. High deposition rates
3. Slag removal
4. Smooth, uniform finish, no spatter
5. Little or no smoke
6. No arc flash
7. High utilization of electrode wire
8. Good for overlay of large areas
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9. Easily automated
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 Electroslag Welding
 ESW is characterized by the joining of
members who are placed edge to edge
so that the joint is vertical
 ESW is not an arc welding process
 Heating from the electrical resistance
of the molten flux to melt the base and
filler metals.
 Vertical ‘casting’ process
 Welding is done in a single pass
 Common defects associated with ESW
1.
Gross porosity
how may cracks may be avoided?
(A) Maintaining proper current
2.
Slag inclusions
(B) Maintaining proper spacing between
electrodes or guide tubes
3.
Large grains
4.
Gross shrinkage
5.
Centerline Cracks due to weld metal shrinkage.
 ESW Advantages
1. Joins heavy sections
2. High deposition rates
3. Single or multiple electrodes
4. Minimum joint preparation
5. Low distortion
 ESW Limitations
1. vertical and flat position only
2. Very extensive setup time
3. Uses water-cooled shoes
4. Flux storage
 arc stud welding
 An arc welding process using an arc between
a metal stud, or similar part, and the other
workpiece..
 DC power source,
 little operator skill is required
 Inspection SW .
 First a visual examination is made to assure the presence of a 360° flash.
 reinforcing fillet, or “flash,” around the entire circumference of the stud base.
 the stud can be either struck with a hammer or pulled to judge its acceptability. OR

torque tested to determine its quality.
 High quality with Arc Stud Welding can be obtained when
(A) Making test before starting.
(B) Using sufficient power energy source.
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 Brazing vs welding Processes
 welding Processes
 The base metals are melted.
 Brazing
 The base metals are not melted.
 The melting temperature of filler metal above 840°F (450°C)
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 Brazing
 The brazing processes achieve a bond between materials by heating them in the
presence of a filler metal that has a liquidus above 840°F (450°C) and below the
solidus of the base metal.
 The filler metal flows between the closely fitting joint surfaces by means of capillary
action.
 Brazing Aspects
 Large surface area
 Very small clearance
 Clean surfaces
 Flux often used
 Capillary action
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 Braze Joint Configurations
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 The most widely used processes are
 torch (TB),
 furnace (FB),
 induction (IB),
 resistance (RB),
 dip (DB),
 infrared (IRB), and
 diffusion brazing (DFB).
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 Brazing Advantages
 Strong joints
 Joins dissimilar metals
 Joins metals to nonmetals
 Joins “unweldable” metals
 Less heat, less distortion
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 Brazing disadvantages
 Cleanliness requirements
 Joint design requirements
 Difficult to inspect
Brazing joint can be inspected by ?
(A) Nondestructive testing methods

PT, RT , UT, AET, Proof testing, Leak testing &Thermal
transfer examination
(B) destructive and mechanical testing methods.

Peel testing ,Tension and shear testing , Metallographic
examination, Fatigue testing, Impact testing &Torsion
testing
 Brazing Discontinuities
 Voids, unbonded areas
 Base metal erosion
 Corrosion by flux
 Trapped flux
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 Soldering
 The base metals are not melted.
 The melting temperature of filler metal below 840°F (450°C)
 The solder is distributed between closely fitted joint surfaces by capillary
action.
 Unsatisfactory joints Soldering generally result from
 poor surface conditions (Contaminated or dirty surfaces)
 Improper joint fit-up, and
 incorrect flux selection
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 Soldering
 Some metals are easier to solder.

Copper, silver, and gold are easy.
 Titanium, magnesium, cast irons, some high-carbon steels, ceramics, and
graphite can be soldered but it involves a process similar to joining carbides:
they are first plated with a suitable metallic element that induces interfacial
bonding.
 Some metals are difficulty to solder
 Iron, mild steel and nickel are next in difficulty. Because of their thin, strong
oxide films.
 stainless steel and aluminium are even more difficult to solder.
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 Soldering methods and equipment
 dip (DS),
 iron (INS),
 resistance (RS),
 torch (TS),
 induction (IS),
 furnace (FS)
 infrared (IRS),
 ultrasonic (USS),
 wave (WS), and cascade soldering (CS
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 Cutting Processes
 Oxyfuel Cutting
 Air Carbon Arc Cutting
 Plasma Arc Cutting
 Mechanical Cutting
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 Oxyfuel Cutting Gases Commonly used
 Acetylene
 Methane
 Propane
 MPS (Methylacetylene-propadiene)
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 Oxyfuel Cutting (OFC)
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 OFC - Kerf and Drag
 OFC Cut
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 OFC Advantages
 Simple equipment
 Very portable
 Cuts thin or thick materials
 Good accuracy
 Manual or mechanized
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 OFC disadvantages
 Inadequate to cut stainless steels.
 the finished cut may require additional cleaning or grinding to prepare it for
welding
 the flame and hot slag produced result in safety hazards for personnel near
the cutting operation
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 Air Carbon Arc Cutting (CAC-A)
 This process uses a carbon electrode to create an arc for
heating along with a high pressure stream of compressed air to
mechanically remove the molten metal.
 it can be used to cut all metals
 It is capable of cutting metals that cannot be cut by the oxyfuel
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gas cutting process.
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 Plasma Arc Cutting (PAC)
 This process is similar in most respects to PAW except that now the purpose
is to remove metal rather than join pieces together.
 Advantages (PAC)
 cutting of non-ferrous metals, PAC is also useful for the cutting of carbon
steels. That’s means can cut all metals
 ability to cut metals which cannot be cut with OFC,
 the resulting high quality cut, and
 increased cutting speeds for carbon steel.
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Q-1 The distance between the tip of electrode and the weld surface is
called
a. Arc force
b. Arc length
c. Arc blow
d. Arc Strike
e. Arc Chamber
Q-2 The function of the covering on a covered arc welding electrode is
providing………
A. Shielding Gas Cover
B. Protective Slag
C. Deoxidized Weld Metal
D. Arc Stabilization
E. All of The Above
Q-3 In the SMAW electrode designation E 308L , what does the
designator 308 signify:
a. Lime coating
b. Alloy type
c. Tensile Strength
d. Hydrogen content
e. Welding Position
Q-4 when are optimum results more likely obtained when using EXX16
and EXX18 low hydrogen electrodes??
(A) When used with a long arc on downhill welding and a short arc on uphill
welding
(B) When stored in a refrigerator when the container has been opened .
(C) When stored in a hold oven at proper temperature
(D) When used with a whipping technique on light gage metal
(E) When replace with Exx13 electrodes on vertical work
Q-5 In SMAW the correct arc length is essential to good welding
performance. Which factors affect arc length?
(A) Electrode classification
(B) Electrode diameter
(C) Welding position
(D) all of the above
(E) Only A and B above.
Q-6 The sketch below shows
a. SMAW
b. GMAW
C. GTAW
d. ESW
e. PAW
Q-7Which of the following is a significant disadvantage of SMAW
compared to GMAW?
a. It is more sensitive to wind and drafts.
b. Shielded gases are usually required.
c. Deposition rates are considerably low .
d. It can only be used on ferrous metals.
e. None of the above.
Q-8 The sketch shows what mode of metal Transfer related to GMAW
Process:
a. Pulsed arc transfer mode.
b. Spray transfer mode.
c. Short circuiting transfer mode.
d. Globular transfer mode.
e. Open circuiting transfer mode.
Q-9 GMAW is essentially replaced for welding process ………………. In
many applications.
a. GTAW
b. SMAW
c. FCAW
d. PAW
e. SAW
Q-10 What does the prefix ‘’ER’’ indicate in the ER 309L filler metal
classification?
(A) The electrode is in a rolled from
(B) It can be used as an electrode or rod
(C) It is for rust-resistant applications
(D) It is intended for reverse polarity application.
Q-11Gas metal arc welding (GMAW) is suitable for what metals?
(A) Carbon steel
(B) Stainless steel
(C) Aluminum
(D) all of the above
(E) Only A and B above
Q-12 In GMAW, which of the following is NOT affected by selecting
shielding gas?
(A) Electrode Extension.
(B) Welding Speed.
(C) Metal transfer mode
(D) Penetration.
(E)Weld metal Mechanical Properties.
Q -13 In GMAW, which of the following is the greatest affected by
selecting shielding gas?
(A) Electrode Extension.
(B) Mechanical Properties.
(C) Welding Speed.
(D) Metal transfer mode
(E) Penetration.
Q-14 FCAW electrode classification uses the letter “ T ” TO INDICATE
which of following electrode constructions?
(A) Tungsten
(B) Tubular
(C) Tantalum
(D) Thorium
(E) Titanium
Q-15 when other welding variables are held constant, increasing the
welding current during FCAW will do which of the following ?
(A) Increase electrode deposition rate
(B) Increase penetration
(C) Produce concave weld beads with poor appearance
(D) All of the above
(E) Only A or B above
Q-16 why is CO2 widely used as a shield gas component for FCAW?
(A) It is not reactive in the arc
(B) It has a reducing effect on components in the weld pool.
(C) It promotes deep penetration and is lower in cost
(D) It promotes short-circuit metal transfer
(E) It reduces the need for de-oxidation elements in the electrode.
Q-17 GTAW can be used to weld most metals, which of the following is
most useful
A. Galvanized Parts
B. Thin Gauge Aluminum
C. Reinforcing rod
C. Heavy Steel Plate
E. Cast Iron
Q-18 GTAW process a typical cause of tungsten inclusion
A. Excessive Fit Up
B. Insufficient Welding Current
C. Straight Polarity Welding
D. Contact on the Electrode Tip with the Weld Pool
E. None of The Above
Q-19 The most accurate regarding the selection of a filler metal of
GTAW application
A. GTAW electrodes are not consumed in the GTAW process
B. AWS not specified the selection of filler metal in GTAW
C. Generally ,filler metals are selected To match the properties of the base metal in the
welded condition
D. Reaction between filler metal and shielding gas is very important
E. Because of tungsten, in GTAW process filler materials do not clean like other process
Q-20 The filler metals for Manual GTAW are usually in which of the
following forms:
A. Cut lengths rods usually 0.9 m (36 inches ) long
B. Large wire spools (30 lbs)
C. 12 inch (0.3 m) coated electrodes
D. Coils of tubular electrode
E. 3.16 inch diameter electrodes
Q-21 What does the prefix ‘’ER’’ indicate in the ER 309L filler metal
classification?
(A) The electrode is in a rolled from
(B) It can be used as an electrode or rod
(C) It is for rust-resistant applications
(D) It is intended for reverse polarity application.
Q-22 Tungsten electrodes for GTAW are classified based upon chemical
composition and rely on which of the following for identification
a. Printed identification on each electrode
b. Heat numbers on the original packing
c. A system of specific color markings on electrode
d. Unique size for each type of electrode
Q-23 Electrodes for GTAW are different from other welding processes in
which of the following ways?
(A) They are non-consumable
(B) they are autogenous
(C) They can be tubular or solid
(D) They contain flux
(E) They do no contribute to conductivity
Q-24 Arc voltage in GTAW is affected by which of the following
parameters?
(A) The amount of thorium in the electrode
(B) The ambient air temperature
(C) The distance between the electrode and the workpiece
(D) The filler metal feed speed
(E) The travel speed
Q-25 Most influence on the shielding effectiveness of argon
A. High Conductivity
B. Low Cost
C. High Density
D. Ability to Form Plasma
E. Ionization potential
Q-26 which of the following would be considered an advantages of the
GTAW process?
(A) Ability to make autogenous welds
(B) No spatter.
(C) High quality weld deposits
(D) Ability to weld almost all dissimilar metals
(E) All of the above .
Q-27 in which of the following ways are fluxes for SAW classified
according to the manner in which they modify the composition of the
weld metal ?
(A)Oxidizing or reducing
(B) Fused or agglomerated
(C) Granular or powdered
(D) neutral, active, or alloy
(E) Covered or self-shielded
Q-28 A CWI shall be familiar with and understand the fundamentals of
what?
(A) SMAW
(B) FCAW
(C) GMAW
(D) GTAW
(E) all of the above
Q-29 Which of the following processes can be used to join quenched
and tempered steels?
(A) SMAW
(B) SAW
(C) GMAW
(D) all of the above
(E) Only B and C above
Q-28 when choosing a welding process, which of the following
considerations is the most important and most expensive?
(A) Selection of the power supply
(B) Selection of the ground clamp
(C) Selection of the electrode holder
(D) Selection of the welding cables
(E) Selection of the welding position desired
Q-29 The sketch below shows
a. SMAW
b. FCAW
c. ESW
d. GTAW
e. SW
Q-28 The sketch shows a test procedure for
a. SMAW
b. GMAW
c. ESW
d. GTAW
e. SW
Q-29 High quality with Arc Stud Welding can be obtained when
a. Making test before starting.
b. Using sufficient power energy source.
c. High skillful operators are required.
d. All of the above.
e. Only a& b.
Q-30 Brazed joints can be tested by which of the following testing
methods
A. UT
B. leak
C. Torsion
D. All of The Above
E. Only A and C above
Q-31 Brazed joints can be destructively tested by which of the following
testing methods?
(A) Metallographic
(B) Peel
(C) Tension
(D) all of the above
(E) None of the above
Q-32 The brazing differs from other welding Processes in that:
A. The base metals are not melted.
B. The melting temperature of filler metal is greater than 840 F
C. no filler metal is used
D. Only A and B above
Q-33 Which of the following is the least factor when selecting a brazing
filler metal?
A. Base Metal
B. Joint Design
C. Service Requirement
D. Brazing process
E. Position
Q-34 In braze welding, flux may be applied by which of the following
methods?
(A) Using a filler rod pre-coated with flux
(B) Introducing flux through the oxyfule gas flame
(C) Brushing the flux on the joint prior to brazing
(D) Any of the above
(E) Only A or B above
Q-35 to be classified as brazing, the joining process must use a filler
metal wire which of the following characteristics?
(A) The filler metal cannot wet the surfaces to be joined
(B) The filler must melt at above 840 F
(C) The filler metal must melt in an oxidizing atmosphere
(D) The filler metal must have acceptable mechanical properties when mixed with
the base metal
(E) The filler metal must have non-ferrous properties
Q-36 Which of the following is not considered soldering process?
A. dip Soldering
B. iron Soldering
C. Resistance Soldering
D. Induction Soldering
E. Cold Soldering
Q-37 The greatest limitation related to using Soldering processes is:
a. Lack of fusion of welds.
b. Great amount of spatter produced.
c. Contaminated or dirty surfaces.
d. High skills & performance required.
e. Used only for joining metals lower than 840 F.
Q-38 which of the following is The most likely problem to be
encountered by soldering process?
a. dissimilar metals being joined.
b. Uncontrolled melting of base materials.
c. Embrittlement in the HAZ.
d. Contaminated or dirty surface condition
e. porosity.
Q-39 The width of the cut produced during a cutting process is referred
to as:
a. Root Opening
b. Kerf.
c. Bevel
d. Bevel Angle
e. Chamfer
Q-40 An advantage of plasma arc gouging over carbon arc gouging
A. Elimination of Carbon Pick Up Problem
B. Less Grinding To Clean Up the Join
C. Less Cost Equipment Problem
D. All of The Above
(E) Only A & B above .
Q-41 Which of the following is true regarding air carbon arc cutting?
(A) Metal removal is accomplished by an oxygen stream
(B) Cutting is accomplished by metal oxidation
(C) It is capable of cutting metals that cannot be cut by the oxyfuel gas cutting
process.
(D) All of the above
(E) Only A and B above
Q-42 Plasma Arc cutting (PAC) is better suited than oxyfuel gas cutting
(OFC) for cutting which of the following materials?
(A) Ferrous sheet metal
(B) Non ferrous metals ( i.e., aluminum ,copper ,brass ,etc)
(C) Any metals with a thickness over 5 inches
(D) Stainless steel and plate
(E) A, B and D above
Q-43 which cutting process in shown below figure
(A) Air carbon arc cutting (CAC-A)
(B) oxyfuel gas cutting (OFC)
(C) Gas tungsten arc cutting (GTAC)
(D) Mechanical cutting
(E) Plasma arc cutting (PAC)
 Welding Terminology
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 Basic considerations in welding
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Butt
Lap
Tee
Corner
Butt
Edge
Spot
Fillet
Plug
 Single sided preparations are normally made on thinner materials,
or when access from both sides is restricted
Single
Bevel
Single
Vee
Single
J
Single
U
 Double sided preparations are normally made on thicker materials,
Double Bevel
Double Vee
Double J
Double U
Groove angle
Groove angle
Angle of
bevel
Groove
Radius
Depth of bevel
Root opening
Root Face
Single -V Butt
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Root Face
Root opening
Single - U Butt
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Weld reinforcement.
Weld metal in excess of the quantity required to fill a weld groove.
 A surfacing weld
 a weld applied to a surface, as opposed to making a joint, to obtain desired
properties or dimensions. Other terms associated with surfacing are:
a) Buildup
 a surfacing variation in which surfacing material is deposited to achieve the
required dimensions.
b) Buttering
 a surfacing variation that deposits surfacing metal on one or more surfaces to
provide metallurgically compatible weld metal for the subsequent completion of a
weld.
c) Cladding,
 a surfacing variation that deposits or applies surfacing material, usually to
improve corrosion or heat resistance.
Weld interface
The boundary between
weld metal and
base metal in a fusion
weld
Depth of fusion
the difference between the fusion
face and the weld interface
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 The welding symbol is the weld symbol with all the additional
element information (e.g., size, pitch, length, etc.) applied to it.
 The weld symbol identifies the specific type of weld (e.g., fillet,
groove, plug, slot, etc.).
 The weld symbol is one of the element of a welding symbol
Required Elements
Optional Elements
• Reference Line - always horizontal
• Arrow
• Multiple reference lines
• Tail
• Weld Symbol
• Dimensions
• Supplementary Symbols
• Finish
• Specification, Process
 Information applicable to the arrow
side of the joint is placed below the
reference line
 Information applicable to the other
side of a joint is placed above the
reference line
 A break in the arrow line
signifies that the member the
arrow points to is the member
receiving the edge
preparation.
 A break in the arrow line
signifies that the member the
arrow points to is the member
receiving the edge
preparation.
 Two or more reference lines may be used to indicate a sequence of
operations.
 The first operation is always on the reference line nearest the arrow.
 The Tail is used to specify welding process information or other such
information needed to convey the necessary welding details.
Arrow side - V- groove
Other side - V- groove
Both sides - V- groove
Back or Backing, single Jgroove, fillet
Single-bevel-groove,
double fillet
Square- groove Weld with MeltThrough
Single-bevel-groove with MeltThrough
Single-V-groove with MeltThrough
 Edge weld with melt-Through
 Depth of Bevel, S, and Size of
Weld, (E) placed to the left of the
symbol
1/4 inch Depth bevel with a 3/8
inch weld
(No dimensions means complete
penetration)
 The Root Opening is placed within
the weld symbol or just outside,
and only on one side of the
reference line
 Inches or mm per shop practice
 Groove Angle is placed just
outside the weld symbol
 Pitch is the distance between centers of adjacent weld
segments. Pitch length is shown to the right of the weld
length dimension
 Chain intermittent weld dimensions are to be placed on
both sides of reference line, and opposite each other
 Staggered intermittent weld dimensions are to be placed
on both sides of reference line, and offset from each other.
 The fillet weld size is shown to the left of the symbol.
Plug Weld Size.
Angle of Countersink.
Depth of Filling.
WELD PITCH )Spacing of Plug Welds.
Number of Plug Welds.
Mechanical Methods:
C = Chipping
G = Grinding
H =Hammering
M = Machining
R = Rolling
U = Unspecified
Q-1 Which of the following is not a recognized AWS Joint type?
A) Butt joint
B) Fillet joint
C) T-joint
D) Corner joint
E) Edge joint
Q-2 The number 1 in the above figure represents which of the following?
A) Beads
B) Weld Root
C) Weld Toe
D) Face Reinforcement
E) Weld Face
Q-3The number 2 in the above figure represents which of the following?
A) Beads
B) Weld Root
C) Weld Toe
D) Face Reinforcement
E) Weld Face
Q-4 The number 3 in the above figure represents which of the following?
A) Beads
B) Weld Root
C) Weld Toe
D) Face Reinforcement
E) Weld Face
Q-5 The number 4 in the above figure represents which of the following?
A) Beads
B) Weld Root
C) Weld Toe
D) Face Reinforcement
E) Weld Face
Q-6 The number 5 in the above figure represents which of the following?
A) Beads
B) Weld Root
C) Weld Toe
D) Face Reinforcement
E) Weld Face
Q-7 The number 1 in the above figure represents which of the following?
A) Weld convexity
B) Weld face
C) Weld root Reinforcement.
D) Weld Face Reinforcement
E) Weld backing
Q-8 The number 2 in the above figure represents which of the following?
A) Weld convexity
B) Weld root
C) Weld root Reinforcement.
D) Weld Face Reinforcement
E) Weld backing
Q-9 The number 3 in the above figure represents which of the following?
A) Weld convexity
B) Weld root
C) Weld root Reinforcement.
D) Weld Face Reinforcement
E) Weld backing
Q-10 The number 4 in the above figure represents which of the following?
A) Weld convexity
B) Weld root
C) Weld root Reinforcement.
D) Weld Face Reinforcement
E) Weld backing
Q-11 Weld reinforcement is best described by which of the following
statements ?
A) Bars that are tacked to back of the welding joint
B) Materials that are inserted into a weld to fill it up
C) The crown of the fillet weld
D) Weld metal in excess of the quantity required to fill the weld groove
E) The degree of penetration of the weld metal into the weld joint
Q-12 Buttering is best described by which of the following statements ?
A) surfacing variation in which surfacing material is deposited to achieve the
required dimensions.
B) surfacing variation that deposits surfacing metal on one or more surfaces
to provide metallurgically compatible weld metal for the subsequent
completion of a weld.
C) a surfacing variation that deposits or applies surfacing material, usually to
improve corrosion or heat resistance.
D) a weld applied to a surface, as opposed to making a joint, to obtain
desired properties or dimensions
Q-13 The number 1 in the below figure represents which of the
following?
A) Depth of fusion
B) Depth of penetration
C) fusion face
D) Weld interface
E) HAZ
Q-14 The number 2 in the below figure represents which of the
following?
A) Depth of fusion
B) Depth of penetration
C) fusion face
D) Weld interface
E) HAZ
Q-15 The number 3 in the below figure represents which of the
following?
A) Depth of fusion
B) Depth of penetration
C) fusion face
D) Weld interface
E) HAZ
Q-16 The number 4 in the below figure represents which of the
following?
A) Depth of fusion
B) Depth of penetration
C) fusion face
D) Weld interface
E) HAZ
Q-17 what is the proper term for the boundary between weld metal and
base metal?
A) Fusion face
B) Weld interface
C) Groove face
D) Fusion interface
E) None of the above
Q-18 What does dimension # 1 designate in the below figure ?
(A) Theoretical throat
(B) Effective throat
(C) Actual throat
(D) Convexity
(E) Size of weld
Q-19 What does dimension # 2 designate in the below figure ?
(A) Theoretical throat
(B) Effective throat
(C) Actual throat
(D) Convexity
(E) Size of weld
Q-20 What does dimension # 3 designate in the below figure ?
(A) Theoretical throat
(B) Effective throat
(C) Actual throat
(D) Convexity
(E) Size of weld
Q-21 What does dimension # 4 designate in the below figure ?
(A) Theoretical throat
(B) Effective throat
(C) Actual throat
(D) Convexity
(E) Size of weld
Q-22 What does dimension # 5 designate in the below figure ?
(A) Theoretical throat
(B) Effective throat
(C) Actual throat
(D) Convexity
(E) Size of weld
Q-23 Weld No.(A) in the above figure is in what position?
(A) Flat Position
(B) Horizontal position
(C) Vertical position
(D) Over Head position
(E) None of the above
Q-24 Weld No.(B) in the above figure is in what position?
(A) Flat Position
(B) Horizontal position
(C) Vertical position
(D) Over Head position
(E) None of the above
Q-25Weld No.(C) in the above figure is in what position?
(A) Flat Position
(B) Horizontal position
(C) Vertical position
(D) Over Head position
(E) None of the above
Q-26 what weld test position is shown in the above figure?
(A) 1G
(B) 1F
(C) 2F
(D) 3F
(E) 4F
Q-27 What is the weld test position shown in the below figure?
(A) 1 G
(B) 2 G
(C) 3 G
(D) 4 G
(E) 5 G
Q-28 The symbol in figure below shows the configuration of a ---------.
(A) u-groove weld
(B) bevel- groove weld
(C) J-groove weld
(D) Fillet weld
(E) flare-v-groove weld
Q-29 Which welding symbol represents a groove weld with MeltThrough?
(A) 6
(B) 3
(C) 7
(D) 10
(E) 8
Q-30 which of the following is represented by the symbol in figure
below ?
(A) An edge weld with melt-through
(B) CJP groove with backing
(C) Flange weld with melt-through
(D) Square groove weld with melt-through
Q-31 Which is the correct welding symbol for the desired weld in figure
below?
(A) A
(B) B
(C) C
(D) D
(E) E
Q-33 Which is the correct welding symbol for the desired weld in figure
below?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
Q-34 Which is the correct welding symbol for the desired weld in figure
below?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
Q-35 Which of the following does the symbol in the above figure specify ?
A) Double bevel groove weld with a 3 mm root opening
B) Double V groove weld with a 3 mm root opening
C) Double bevel groove weld with a 3 mm depth of bevel on other side
D) Double V groove weld with a 3 mm depth of bevel on other side
E) Double bevel groove weld with a 3 mm root face
Q-36 Which welding symbol represents an Intermittent Fillet Weld?
(A) 1
(B) 9
(C) 4
(D) 7
(E) 6
Q-37 Which welding symbol represents a plug weld Depth of fill ?
(A) 6
(B) 3
(C) 7
(D) 5
(E) 8
Q-38 The NDT symbol shown in the above figure refer to?
A) Visual test & penetrant test made on both side of the part
B) Visual test mad on the other side of the part & penetrant test made on arrow side
C) Visual test mad on arrow side & penetrant test made on the other side of the part
D) Visual test mad on the back of the part & penetrant test made on the front of the part
E) None of the above
Q-39 The symbol in Figure below requires what kind of the testing?
(A) penetrant testing on the other side of part
(B) proof testing on the other side of the part
(C) penetrant testing on the arrow side of the part
(D) proof testing on the arrow side of the part
(E) penetrant and radiographic testing from the other side
Q-40 What is required by the nondestructive testing symbol shown
below ?
(A) Radiographic testing at the 3 inch location for 8 inches.
(B) 3 radiographic tests with a pitch of 8 inches.
(C) 3 inch long radiographic tests every 8 inches.
(D) Radiographic testing for 8 inches at 3 random locations.
(E) 8 radiographic tests every 3 inches.
Q-41 What does the supplementary symbol in the figure below?
(A) Laser radiation
(B) Neutron radiation source
(C) Phased array
(D) Radiation direction
(E) Oblique lighting
Q-42 The welding symbol below indicates
a. double bevel-groove weld ,ultrasonic test either in filed side
b. double bevel-groove weld ,ultrasonic test both in filed side
c. double V-groove weld , ultrasonic test either in filed side
c. double V-groove weld , ultrasonic test both in filed side
e. none of the above
Q-43 Which of the symbols shown in figure below is used to indicate a
field weld as noted in the current edition of AWS A2.4 standard symbols
for welding brazing and nondestructive examination?
(A) 1
(B) 2
(C) 3
(D) 4
(E) Field welds are not shown on the drawings.
Q-45 Which welding symbol represents a weld that extends all around
the joint?
(A)
9
(B)
4
(C)
7
(D)
3
(E)
8
Q-46 What is the first operation specified in the below figure?
A) Conduct MT
B) Back-Gouge
C) Weld the U groove
D) Weld the V groove
E) Conduct CJP
Q-47 What is the last operation specified in the below figure?
A) Conduct MT
B) Back-Gouge
C) Weld the U groove
D) Weld the V groove
E) Conduct CJP
Q-48 where is MT +VT Performed as specified in the below figure?
A) On the V- groove face surface
B) On the V- groove intermediate surface
C) On the backgouged surface.
D) On the finish weld V- groove weld surface
E) On the finish weld U- groove weld surface
Q-49 Which of the following is represented by the symbol as specified
in the below figure?
A) A spot weld with a 1/2 –inch nugget.
B) A plug weld with a 1/2 –inch weld size.
C) A slot weld with a 1/2 –inch nugget.
D) A plug weld with a 1/2 –inch overlap.
E) A plug weld with a 1/2 –inch fill depth.
Q-50 Which of the following is represented by the symbol as specified
in the below figure?
A) Weld pitch.
B) overlap.
C) Weld length.
D) Fill depth.
E) Countersink angle.
Q-51 Which of the following is represented by the symbol as specified
in the below figure?
A) Two 1/8 inch fillet welds on 4 inch centers.
B) Four 2 inch fillet welds inches long at 1/8 inch spacing .
C) Intermittent 1/8 inch fillet welds 2 inches long on 4 inch center.
D) Intermittent 1/8 inch fillet welds 4 inches long on 2 inch center.
E) None of the above.
Q-52 when added to a welding symbol, what does the symbol in the
below figure require?
A) Grind flush.
B) Grind in on direction.
C)Groove weld.
D) Gouge flat.
E) Gas backing.
Q-53 what is the correct welding symbol for the desired weld shown in
the below figure?
A) 1.
B) 2.
C) 3.
D) 4.
E) 5.
 Destructive Testing
 destroying, a part, or a portion thereof, to determine its properties
 Nondestructive Testing
 Does not affect the serviceability of the part after testing is completed
 Mechanical Properties of Metals
 The important mechanical properties of metals

Strength

Ductility

Toughness

Fatigue Strength
Mechanical Test Samples
Tensile Specimens
CTOD Specimen
Bend Test
Specimen
Charpy Specimen
Fracture Fillet
Specimen
 Strength
 The property of metals that
describes their ability to carry a load
 Two common methods of
expression:
 Ultimate tensile strength (UTS)
 Yield strength (or yield point)
 Tensile Testing
 Metal Behavior Under Load
 Elastic - No permanent deformation
 Plastic - Permanent deformation.
 Offset Method
 Used for Deterring Yield Point
 Usually Offset at 0.2% (0.002 IN/IN)
 Line Parallel to Elastic Limit
 Intersection With Curve Is Y. P
 The result of the tensile test include
 Ultimate Tensile Strength
 Yield Strength
 Percent Elongation
 Percent Reduction of Area
 Ultimate Tensile Strength
Maximum load applied = 22000 Ib.
Least cross sectional area = 0.5 in2
UTS =
Maximum load applied
cross sectional area
UTS =
22000
0.5
UTS = 44000 psi= 44 ksi
 Percent Elongation
Original gage length = 2.0 in.
Final gage length
= 2.6 in.
%Elongation = final length - original length x 100
original length
%Elongation = 2.6 - 2.0 x 100 = 30%
0.2
 Percent Reduction of Area
Original area
= 0.2 in.2
Final area
= 0.1 in. 2
%Reduction of area (%RA) = ?
%RA =
original area - final area x 100
original area
%RA = 0.2 - 0.1 x 100 = 50%
0.2
Stress-Strain Diagram
High and Medium Strength Steels
High Strength Steel
High Carbon Spring Steel
Medium Strength Steel
 Hardness
 Ability to resist indentation
 hardness tests
 Brinell
 Rockwell
 Hardness Tests Microhardness
 Vickers
 Knoop
 Indenters, and Shapes of Indentation
 Brinell
 can use it DT or NDT
Approximate Tensile Strength = BHN X 500
 Rockwell
 uses both minor and major load
 Microhardness
 Two Major Types
 Vickers
 Knoop
 Temperature Effects
 As metal temperatures increase:
Strength decreases
Hardness decreases
Ductility increases
 Toughness
 “The ability to absorb energy”
 The common notch toughness or impact tests include
 Charpy V notch
 crack tip opening displacement (CTOD).
 Charpy Testing
 Charpy Testing
Transition Temperature Samples
 Charpy Test Results
 Energy absorption - Ft. lbs.
 Lateral expansion - Mils
 Ductility
 The ability of a metal to deform without breaking
 Brittle vs Ductile Failure
Brittle
Ductile
 Percent elongation
 Percent reduction of area
 Transition Temperature
 The temperature at which a metal fracture mode changes from ductile
to brittle
 Fatigue Strength
 The strength of a metal when exposed to
repeated reversals of cyclic stresses
 Endurance Limit
 “The maximum stress at which no failure
will occur, regardless of cycles”
 Only Ferrous alloys and titanium alloys
have Endurance Limit

Other structural metals such as
aluminium and copper, do not have
Typical S-N Curves
 Soundness
 “Freedom from discontinuities”
 Soundness Testing
 Bend testing
 Nick-break
 Fillet break
Wrap-around
Bend Test Jig
Guided Bend Test Jig
Transverse Weld Bend Specimens
“t” up to 12 mm
Root / face
bend
Thickness of material - “t”
“t” over 12 mm
Side bend
Bend Test Samples
Transverse Weld Bend Specimens
Bend Test Samples
Longitudinal Weld Bend Specimens
Face bend
Side bend
Root bend
Defect indication
Generally this
specimen would be
unacceptable
Acceptance for
minor ruptures on
tension surface
depends upon code
requirements
Fillet Break - Sample Fracture
Fillet Break Specimen - T-Joint
Nick Break Test Samples
Evaluation of Nick-Break
Test
 Metallographic Testing
 Metallographic Testing
 Macroscopic – specimens examined at magnification of
10x or lower
 Microscopic - specimens examined at use magnifications
greater than 10X, usually 100X or higher.
 Photomacrograph
 Macroscopic - 10x or lower
 Macro specimen “for determining
such as depth of fusion ,depth of
penetration ,effective throat, weld
soundness, degree of fusion,
presence of weld discontinuities,
weld configuration, number of
passes”
 Photomicrograph
 Microscopic - usually 100X or higher100X
 Micro specimen “used to determine
various features as well included are
microstructure constituents,
presence of inclusions, presence of
microscopic defects, and nature of
cracking”
 Photomicrograph
 Microscopic of the welded joint
including:a) Base metal (BM).
b) Fusion Zone- Weld metal (WM).
c) Coarse grain heat affected zone
(CGHAZ).
d) Fusion line (FL).
e) Fine grain heat affected zone
(FGHAZ).
 Chemical Properties
 Metals are mixtures of elements, and are referred to as
alloys
 Minor changes in alloy composition can have major
effects on alloy properties such as mechanical strength,
corrosion resistance
 Common Steel Alloys
 Effects of Carbon on the Properties of Iron
0.83 % Carbon (Eutectoid)*
Tensile Strength
Hardness
Ductility
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.2 1.4 1.6 % Carbon
 Elements in Steels
 C
- Most important
 Mo - Hardenability
 S
- Undesirable
 Ni
- Toughness, Ductility
 P
- Undesirable
 Al
- Deoxidizer
 Si
- Deoxidizer
 V
- Hardenability
 Mn - Combines with S
 Cr
- Hardenability, Corrosion Resistance
 Nb - Stabilizer
 Alloying
 “Adding elements to change mechanical or physical properties”
 Two Methods of Alloying:
 Interstitial
 Substitutional
 Interstitial Alloying
 Atoms Go Into the Space of the Atomic Structure
 Example - C Into Fe
 Substitutional Alloying
 Add Atoms Almost the Same Size Which Replace the Other Element in That
Placement
 Example - Cr Into Fe
 Dissolved Gases
 Hydrogen
 Oxygen
 Nitrogen
 Dissolved Gases in the molten weld metal can cause

Embrittle ( crack) steels,
 Porosity
 Stainless Steels
 The stainless steels are defined as having at least 12% chromium.
 The five main classes of stainless steels
 Ferritic- identified by “400” series grades, A 430
 Martensitic- identified by “400” series grades, A 416
 Austenitic-more common stainless steels, identified by the “200” and “300” series grades;
such as A 304 and A 316.
 Precipitation Hardening (PH)- One of the common PH stainless steels is a 17-4 PH grade.
 Duplex -are approximately half ferrite and half austenite at room temperature with
improved resistance to chloride stress corrosion cracking. A popular duplex grade is
2205.
 Sensitization of Austenitic Alloys
 “Formation of chromium carbides between
800 - 1600 degrees F”

The most severe temperature for this
formation is about 1250°F,

the chromium and carbon present in the
metal combine to form chromium
carbides.

reduction of the chromium content within
the grain itself adjacent to the grain
boundary, called chromium depletion.

reduced corrosion resistance
 Sensitization of Austenitic Alloys
 Sensitization reduces the corrosion resistance in many environments
 In certain corrosion environments, the edges of the grains corrode at a high rate, and this
is called intergranular corrosion attack, or IGA
 Sensitization of austenitic stainless steels during welding can be prevented by
several methods.

Heat treatment ( SAWQ )

Solution annealing + Water quenched

Solution annealing, reheat treating the complete structure by heating to 1950°F–2000°F.

Following rapidly quenched in water to avoid reformation of the chromium carbides, to Maximize
Corrosion Resistance

Stabilized grades

Use of Stabilizers (T & Nb )

When titanium is added, we have the austenitic stainless alloy 321; when niobium is added, we
have the 347 grade

Low carbon grades

Use of ELC OR L Alloy ( less than 0.03%.)
 Distortion
 Distortion will occur in all welded joints if the
material are free to move i.e. not restrained
 Restrained materials result in low distortion
but high residual stress
 Highly restrained joints also have a higher
crack

The action of residual stress in welded joints
is to cause distortion
Angular Distortion
 Control of distortion my be achieved in the following way
 Pre-set or Offsetting:

The amount of offsetting required is generally a function of trial and error.
 Control of distortion my be achieved in the following way
 Back-step welding technique
1.
2.
3.
4.
5.
6.
 Control of distortion my be achieved in the following way
 Clamping and jigging:
 Residual Stresses
 Residual Stress Caused by the Heating, Melting and Cooling and Solidifying of
Metals

Remain after welding is completed (residual stress)

Can cause distortion
 welding stress exceeds yield strength of material

Can cause cracking
 welding stress exceeds tensile strength of material
 Residual Stresses
 Relieved Residual Stresses by three methods
 Thermal - Controlled Heating and Cooling (PWHT)
 Vibratory Treatment - High Frequency Probes
 Mechanical Treatment ( Peening) - Use of Heavy
Pneumatic Hammer

Most Stress Relief Done Thermally (PWHT), but
Peening During Welding Can Be Effective, As Is
Vibratory Stress Relief.
 Heat Treatments For Steels
All heat treatments applied to metals are cycles of 3 elements.
Temp
1)
Heating
2)
Soaking
3)
Cooling
2
1
3
Time
 Heat Treatments For Steels
 Preheating
 Stress Relieving
 Normalizing
 Annealing
 Quenching and Tempering
 Others
 Preheat
 Preheat with higher carbon content or increased workpiece thickness, a higher
preheat and inter-pass temperature should be used to

Decrease the weld cooling rate

Reduces distortion

Reduces hydrogen

control the weld hardness

Minimize the risk of cracking.
 The primary purpose of preheating is to minimize the risk of hydrogen cracking.
 Preheat for steel
C.E.
< 0.45
0.45 - 0.60
>0.60
Preheat Temperature
Optional
2000 - 4000 F
4000 - 7000 F
 Carbon Equivalent ( C.E.)
CE = % C + % Mn + % Ni + % Cr + % Cu + % Mo
6
15
5
13
4
 The carbon equivalent determine hardenability of that steel.
 The carbon equivalent unit is employed to predict the tendency to Martensite
 Heat Treatments For Steels
PWHT:
 Used after welding to release residual stresses, caused by welding operations
 Steels is heated above its LCT, or Lower critical temperature
 Temperature: 550-650 C no phase transformation
 Cooling: Hold, furnace or controlled cooling
 Relieves residual stresses , reduces hydrogen levels, prevents stress
corrosion cracking
 Heat Treatment for steel
Annealing:
Used to make metals soft and ductile
 Steels is heated above its UCT, or upper critical temperature
 Temperature: 920°C hold for sufficient time (full austenitization)
 Cooling: Hold (soaked ) for 1 hour/25mm , slow cooling in furnace
 Produces a coarse grain structure & low toughness
Normalising:
Used to make steels tough
 Steels is heated above its UCT, or upper critical temperature
 Temperature: 920°C hold for sufficient time (full austenitization)
 Cooling: Hold (soaked ) for 1 hour/25mm , slow cooling in air
 Produces a fine grain structure with good toughness
 Heat Treatment for steel
Quenching:
Used to make some steels harder
 Steels is heated above its UCT, or upper critical temperature
 Temperature: 920°C hold for sufficient time (full austenitization)
 Cooling: Fast cool, quench in water, oil.
 Produces high tensile strength and hardness.
Tempering:
Used after Quenching to balance the properties of Toughness &
Hardness
 Steels is heated above its LCT, or Lower critical temperature
 Temperature: 550°C to 700°C hold for sufficient time
 Cooling: slow cooling in air
 Produces Increases toughness of quenched steel, relieves residual stres
A
B
(A) Normalised
(B) Fully Annealed
(C) Water-quenched
(D) Water-quenched & tempered
C
D
Q-1 The sketch below is a specimen for :
(A) Bend Test
(B) Tensile Test
(C) Charpy V Test
(D) Neck Break Test
(E) Macro Specimen Test
Q-2 The property of metals that describes their resistance to indentation
is called:
a. strength
b. toughness
c. hardness
d. ductility
e. none of the above
Q-3 Hardness test method(s) for metal include(s) which of the
following?
(A) Rockwell
(B) knoop
(C) vickers
(D) brinell
(E) all of the above
Q-4 Hardness of base metals can be affected by which of the following
conditions?
(A) heat treatment
(B) Cold working of the metal
(C) composition of the base and metal
(D) metallurgical effects of the welding process
(E) all of the above
Q-5 Which of the following destructive tests may be used to determine
toughness?
A. Drop-weight
B. Crack tip displacement (CTOD)
C. Charpy V-notch (CVN)
D. All of the above
E. Only A and C only
Q-6 The sketch below is a specimen for :
(A) Bend Test
(B) Tensile Test
(C) Charpy V Test
(D) Neck Break Test
(E) Macro Specimen Test
Q-7 The fillet weld break test is used to check for which of the
following?
(A) quality of fractured the weld metal
(B) compression strength of the weld joint
(C) ductility of the weld metal
(D) the weld s resistance to lamellar tearing
(E) impact strength of the weld joint
Q-8 What can be determined with metallographic:
A. Depth of weld penetration
B. Number of weld passes
C. Weld of ductility
D. All of the above
E. Only A and B above
Q-9 When the weld structure is to be examined at magnification of 10x
or lower, what kind of specimens are used?
A. Macro specimens
B. Micro specimens
C. Tensile specimens
D. Charpoy specimens
E. Chemical Tests
Q-10 Microscopic examination will reveal the microstructure of which of
the following?
(A) base metal
(B) heat-affected zone
(C) fusion zone
(D) all of the above
(E) only B and C above
Q-11 Which of the following materials have the best weldability ?
A. Low carbon steel
B. Medium carbon steel
C. High carbon steel
D. Cast iron
E. Low alloy steel
Q-12 Sensitization of stainless steel primarily refers to its loss of which
property?
(A) Strength
(B) Toughness
(C) Ductility
(D) Corrosion resistance
(E) Impact resistance
Q-13 Which of the following is/are sometimes used to control distortion
in a weldment?
(A) Peening
(B) Preheating
(C) Fixtures and stress relief
(D) Back step welding
(E) all of the above
Q-14 Back step sequence welding is often used ----------.
(A) For ease of operation
(B) For tacking the welded material
(C) To speed up welding
(D) To reduce distortion
(E) To prevent crater cracks
Q-15 The maximum preheat and inter-pass temperatures for quenched
and tempered steel are specified for what reason?
A. Minimize deposit rate
B. Maintain the strength HAZ
C. Avoid excessive weld metal strength
D. Avoid hydrogen cracking
E. Minimize dilution
Q-16 Which of the following slows the rate of cooling in a weld bead?
(A) Decreasing the Heat Input per Inch of Weld
(B) Preheating the Weldment
(C) Reducing the Electrode Size
(D) Increasing the Speed of Travel
Q-17 A stress relief heat treatment {approximately 1150 F (620 C) on
carbon steel} is intended to accomplish which of the following?
A. Change the microstructure of the weld
B. Increase the tensile strength of the weld
C. Reduce the residual stress across the weld
D. Increase the impact strength of the weld
E. Provide a method of oven heating for the removal of gas pokets trapped in
the weld
Q-18 The carbon equivalent unit is employed to predict the tendency to
form which of the following:
A. Lammelar Pearlite
B. Upper Bainite
C. Martensite
D. Austenite
E. Acicular Ferrite
Q-19 The base metal next to the weld that has been heated to a
sufficiently high temperature to cause a change in microstructure is the
(A) Tempered zone
(B) heat-affected zone
(C) Untempered zone
(D) Pearlite area
(E) Base plate
 Discontinuity Versus Defect
 An interruption of the typical structure of a material, such as

a lack of homogeneity in its mechanical, metallurgical, or physical characteristics.
 A discontinuity is not necessarily a defect.
 Defect is
 a flaw or flaws
 by nature or accumulated effect renders a part or product unable to
meet minimum applicable acceptance standards or specifications.
 the term designates rejectability.
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1) Incomplete root penetration.
2) Lack of root fusion.
3) Root concavity.
4) Burn through.
5) Excess penetration.
6) Root piping.
7) Oxidized Root (Root Coking)
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1) Incomplete root penetration.
DEFINITION:
Failure of weld metal to extend into the root of a joint.
CAUSES:
1) Root faces too large
2) Root gap too small
3) Electrode diameter too large
4) Incorrect electrode angle
5) Arc length too long
6) Travel speed too high for current
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1) Incomplete root penetration.
Note: two straight edges
equal to the root gap
preparation. Also absence
of weld metal
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Lack of root penetration
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2) Incomplete root fusion.
DEFINITION:
Lack of union at the root of the weld.
CAUSES:
1) Amperage too low / too high
2) Contaminated weld preps
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Weld Root Imperfections
Lack of Root Fusion
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Lack of Root Penetration
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Weld Root Imperfections
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Lack of root penetration
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Lack of root fusion
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3) Concave root (suckback).
DEFINITION:
A shallow groove that may occur in the root of a butt weld.
CAUSES:
1) Root face too large
2) Low arc energy
3) Excessive back purge
4) Excessive root grinding
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3) Concave root (suckback).
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Concave root
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4) Excessive Root Penetration.
DEFINITION:
Excess weld metal protruding through the root
of a fusion weld made from one side only
CAUSES:
1) Excessive amperage during welding of root
2) Excessive root gap
3) Poor fit up
4) Excessive root grinding
5) Improper welding technique
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4) Excessive Root Penetration.
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Excess root penetration
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5) Burn Through.
DEFINITION:
A localized collapse of the molten pool due to
excessive penetration, resulting in a hole in
the weld run.
CAUSES:
1) Excessive amperage during welding of root
2) Excessive root grinding
3) Improper welding technique
4) Slow travel speed
5) Large root gap/small root face (irregular fit up)
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5) Burn Through.
Burn Through
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6) Root Piping (Hollow Bead)
ROOT PIPING (HOLLOW BEAD)
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7) Oxidized Root (Root Coking).
DEFINITION:
During TIG , Purging gas used
to Prevent Oxidation in the root area
during welding stainless steel, titanium
and other corrosion-resistant materials
CAUSES:
1) Loss or insufficient back purging gas
2) Most commonly occurs when welding
stainless steels
3) Purging gases include argon, helium
and occasionally nitrogen
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1) Lack of side wall fusion.
2) Lack of inter run fusion.
3) Porosity.
4) Slag inclusions.
5) Tungsten Inclusion
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1) Lack Of Side Wall Fusion.
DEFINITION:
Lack of union in a weld.
CAUSES:
1) Contaminated weld prep.
2) Amperage too low (Insufficient heat input )
3) flooding the joint with too much weld metal
(blocking Out)
4) improper joint design
Lack of sidewall fusion + incomplete filled
groove (underfill)
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2) lack of interun fusion
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3) Porosity.
DEFINITION:
 A group of gas pores, formed by entrapped
gas during the solidification of molten
metal.
Clustered porosity
Linear porosity
Piping porosity or worm holes
or blow holes
POROSITY
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4) Slag inclusions
DEFINITION:
Slag entrapped within the weld
CAUSES:
1) improper techniques.
2) improper manipulation of the welding
electrode
3) insufficient cleaning between passes.
Slag Inclusion
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5) Tungsten inclusions
DEFINITION:
A tungsten particle embedded in a weld. (Typically GTAW & PAW only)
CAUSES:
1) amperage too high,
2) electrode tip not snipped,
3) electrode contact with the weld pool.
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1) Arc strikes.
2) Spatter.
3) Porosity.
4) Crater pipe.
5) Undercut.
6) Overlap.
7) Incompletely filled groove (Underfill).
8) Excess weld metal.
9) Poor weld profile.
10) Misalignment (hi-lo)
11)Surface cracks.
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1) Arc Strike (STRAY FLASH)
DEFINITION:
A localized coalescence outside the weld zone
CAUSES:
1) Accidental striking of the arc onto the
parent material
2) Faulty electrode holder
3) Poor cable insulation
4) Poor return lead clamping.
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2) Spatter
DEFINITION:
Small particles (droplet) of weld metal
expelled from the welding operation
which adhere to the base metal surface
CAUSES:
1) Excessive arc energy
2) Arc - blow
3) Damp electrodes
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3) Surface porosity
DEFINITION:
A gas pore is a cavity generally under 1.5mm in
dia. Porosity is a group of gas pores.
CAUSES:
1) Excessive arc energy
2) Arc - blow
3) Damp electrodes
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4) Crater pipe
DEFINITION:
A depression due to shrinkage at the end of a
weld run, where the source of heat was
removed.
CAUSES:
1) Too fast a cooling rate
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5) Undercut.
DEFINITION:
A groove cut at the toe of the weld
and left unfilled.
CAUSES:
1) High welding speed
2) Wrong electrode angle
3) Excessive weaving
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Undercut
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5) Undercut.
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5) Undercut.
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Root undercut
Cap undercut
462
6) Overlap
DEFINITION:
When the face of the weld
extends beyond the weld toe.
CAUSES:
1) Slow travel speed
2) High amperage
3) Welding technique
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COLD LAP/OVERLAP
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7) Incompletely filled groove (Underfill).
DEFINITION:
The weld surface is below the
adjacent surfaces of the base
metal .
CAUSES:
1) Improper welding
techniques
2) Travel speed too high
Incompletely Filled Groove/lack
of sidewall fusion
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8) Excess weld metal.
DEFINITION:
Additional weld metal, at either the root
or the face, which may or may not
be acceptable. Excess weld metal can
cause a poor toe blend.
CAUSES:
1) Slow travel speed
2) Incorrect welding technique
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8) Excess weld metal.
WELD APPEARANCE - TOE BLEND
>3mm
 3mm
GOOD
POOR
> 3mm +
cold lap
> 3mm
POOR
POOR
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9) Poor Profile .
DEFINITION:
A non uniform/irregular appearance at either
the weld face or root. Can include excessive
root penetration/cap height
and poor cap profile.
CAUSES:
1) Poor welding technique.
2) Too slow/fast travel speed
3) Arc blow
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Poor profile /
bulbous contour
467
9) Poor Profile .
WELD APPEARANCE - WIDTH
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REGULAR
IRREGULAR
IRREGULAR
IRREGULAR
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9) Poor Profile .
Incorrect Weld Profile
Overlap of a weld
10) Misalignment (hi-lo).
DEFINITION:
Amount a joint is out of alignment at the root.
CAUSES:
1) Carelessness. Also due to joining different thicknesses (transition thickness)
Linear Misalignment
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11) Cracks.
DEFINITION:
A linear discontinuity produced by fracture.
Welds, Cracks
Longitudinal (centerline)
Longitudinal (HAZ)
Transverse Crack
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Crater
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11) Cracks.
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Longitudinal Crack
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11) Cracks.
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Transverse Crack
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11) Cracks.
Toe Cracks
• Toe cracks occurring in service
are often the result of fatigue
loading of welded components.
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Hot Crack Vs. Cold Crack.
• Hot Crack is intergranular.
• Cold crack may be intergranular or transgranular.
Transgranular
Intergranular
Underbead Cracks

Underbead crack is located in HAZ.

Adjacent to the weld fusion line and running parallel to the
weld interface.

It takes hours after welding to appear (Delayed cracks).

So if expected, final inspection should not be performed until
48 to 72 hours after the weld has cooled to ambient
temperature.

High strength steels (HSLA) ,T&Q steel are susceptible to this
cracking type.

They result from the presence of hydrogen in the weld zone.
• Hydrogen could come from filler metal, base metal, surrounding
atmosphere or organic contamination.
Cellulosic electrodes produce
hydrogen as a shielding gas
Hydrogen produced from
oil, or paint on plate
Hydrogen absorbed in
a long, or unstable arc
Hydrogen crack
H2
Martensite forms from γ
H2
H2 diffuses to γ in HAZ
Underbead Cracks
 Best techniques for the prevention of underbead cracking is:
 To eliminate sources of hydrogen when welding susceptible materials.
 With SMAW low hydrogen electrodes may be used.
 Preheat may help eliminate this cracking problem.
11) Cracks.
Toe Cracks
• Toe cracks occurring in service
are often the result of fatigue
loading of welded components.
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11) Cracks.
Solidification Cracking Fe Steels
Liquid Iron Sulphide films
Solidification crack
*
Contractional strain
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11) Cracks. Prevention of Solidification Cracking
Add Manganese to weld metal *
Spherical Mn Sulphide balls
form between solidified grains
Cohesion and strength
between grains remains
Contractional strain
1) Lamination
2) Seams
3) Laps
4) Delamination
5) Lamellar tears
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During rolling at mill
laminations that have separated due to stresses.
During welding or after welding
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1) Lamination
DEFINITION:
 “A discontinuity with separation or weakness generally aligned parallel to the
worked surface of a metal”
 If there is slag or blowholes in the part, it will elongate forming Lamination.
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1) Lamination
Plate Lamination
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2) Delamination
DEFINITION:
 “Delaminations are laminations that have separated due to stresses.”
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3) Seams
DEFINITION:
 Straight Line longitudinal crevices or openings that may appear on surface.
 They differ from laminations in that they are open to the rolled surface of the
metal instead of the edge.
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Cluster
Seams
486
4) Laps
DEFINITION:
 Laps are the result of overfilling in the mill passes that causes fins or projections
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5) Lamellar tears
DEFINITION:
 Lamellar tears are discontinuities that occur during or after welding.
 They usually appear as a stair step defect caused by contraction forces during
solidification.
 They may extend over long distances and are deeper than heat-affected zone
cracks.
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Q-1 Incomplete joint penetration can be caused by which of the
following?
(A) Insufficient root opening
(B) Excessive travel speed
(C) Excessive electrode diameter
(D) all of the above
(E) Only A and C above
Q-2 Which of the following can cause incomplete fusion?
(A) metal flooding a head of the arc
(B) Insufficient heat input
(C) Proper joint design
(D) Any of the above
(E) Only A and B above
Q-3 What is the discontinuity shown at No. 1 in a below figure?
(A) Underfill
(B) Toe Crack
(C) Overlap
(D) Undercut
(E) Incomplete fusion
Q-4 What is the discontinuity shown at No. 2 in a below figure?
(A) Underfill
(B) Toe Crack
(C) Overlap
(D) Undercut
(E) Incomplete fusion
Q-5 What is the discontinuity shown at No. 3 in a below figure?
(A) Underfill
(B) Toe Crack
(C) Overlap
(D) Undercut
(E) Incomplete fusion
Q-6 Which of the following the may minimize slag entrapment ?
(A) changing the electrodes types
(B) thorough stag removal between passes
(C) proper bead placement
(D) all of the above
(E) only B and C above
Q-7 Why should inter-pass cleaning be verified?
(A) to ensure slag removal
(B) to avoid welding over cracks
(C) to avoid subsequent porosity
(D) to avoid subsequent incomplete fusion
(E) All of the above
Q-8 Which of the following is a typical of tungsten inclusion in GTAW
Weld?
A. Excessive Fit Up
B. Insufficient Welding Current
C. Straight Polarity Welding
D. Contact on the Electrode Tip with the Weld Pool
E. None of The Above
Q-9 Which of the following is/are recommended to prevent cracking in
the welding low-alloy steel?
(A) Controlling hydrogen content during welding
(B) Using minimum required preheat and inter-pass temperature
(C) Using grades with low carbon and alloy content
(D) all of the above
(E) Only B and C above
Q-10 In radiography, a weld which contains a large crack ,how will
appear on the film ?
(A) as a fine dark transverse line.
(B) as a light irregular transverse line.
(C) as a fine dark longitudinal line.
(D) as either a dark or light irregular
(E) A and C Above
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NDT
Surface
Surface/sub-surface and
Volumetric
1.Visual Testing(VT)
1.Radiography Testing(RT)
2.Magnetic Particle Testing (MT)
2.Ultrasonic Testing(UT)
( surface and near surface , applied on only ferromagnetic material)
3. Penetrant Testing (PT) (any defects open to surface)
4. Eddy Current (ET) ( surface and near surface)
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☼ Visual examination



is the most extensively used NDE method for welds.
The oldest and most widely used inspection techniques
The eyes of inspector are the only ‘equipment’ used for the
inspection

Applicable to virtually any material at any stage of
manufacture at any point in its service life

VT is commonly performed on castings, forgings, and
welds and it is performed after machining processes as
well.

It includes either the direct or indirect observation of the
exposed surfaces of the weld and base metal.
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☼ Direct visual examination

is conducted when access is sufficient
to place the eye within 6 in. through
24 in. (150 mm through 600 mm) of
the surface to be examined and at
an angle not less than 30 degrees to
the surface as illustrated in Figure.

Mirrors may be used to improve the
angle of vision.
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ASME
Section V,
Article 9, lists
requirements
for visual
examination.
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• Codes and specifications may list compliance with these requirements as
mandatory.
• Some requirements listed in this article include the following.
• a) A written procedure is required for examinations.
• b) The minimum amount of information that is to be included in the
written procedure.
• c) Demonstration of the adequacy of the inspection procedure.
• d) Personnel are required to demonstrate annually completion of a J-1
Jaeger-type eye vision test.
• e) Direct visual examination requires access to permit the eye to be
within 6 in. through 24 in. (150 mm through 600 mm) of the surface, at
an angle not less than 30 degrees.
• f) The minimum required illumination of the part under examination.
• g) Indirect visual examination permits the use of remote visual
examination and devices be employed.
• h) Evaluation of indications in terms of the acceptance standards of the
referencing code.
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☼ Optical Aids
 Optical aids used in visual inspection
include the following.
a) Lighting

the inspection surface illumination is of
extreme importance.

Adequate illumination levels should be
established in order to ensure and effective
visual inspection.

Standards such as ASME Section V Article 9
specify lighting levels of 100 foot-candles
(1000 lux) at the examination surface.
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 Effective program of visual inspection
 It has been proven that EFFECTIVE program of visual inspection will discover
vast majority of the defects which would be found later using expensive NDE
methods
 This only possible when the VT is accomplished:
 BEFORE, DURING and AFTER welding
 By a trained and qualified inspector (that’s why AWS developed the CWI program)
 Proper tools
 Why VT is very cost effective:
 Relative simplicity
 It is least expensive inspection method
 Minimal amount of equipment required
 Minimize the repair time and cost;
 It allows for detection and correction of many discontinuities before weld
completion
 Application of VT
 Before welding
 During welding
 After welding
☼ Optical Aids
 Optical aids used in visual inspection
include the following.
b) Mirrors
 valuable to the inspector allowing them to
look inside piping, threaded and bored
holes, inside castings and around
corners if necessary.
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☼ Optical Aids
 Optical aids used in visual inspection include the following.
c) Magnifiers
 helpful in bringing out small details and defects.
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☼ Optical Aids
 Optical aids used in visual inspection
include the following.
d) Borescopes and Fiberscopes
 widely used for examining tubes, a deep
hole, long bores, and pipe bends, having
internal surfaces not accessible to direct
viewing metal.
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☼ Weld Examination Devices
 Typical inspection tools for weld inspection include the following.
a) a) Inspector’s kit
 contains some of the basic tools needed to perform an adequate visual examination of a weld
during all stages of welding {Before welding ,During welding and After welding}
 It includes as the following:-
1.
2.
3.
4.
5.
6.
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6 inch Ruler
1 inch Micrometer
Metric Dial Caliper
Palmgren Gage
Undercut Gage
Fillet Weld Gages
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☼ Weld Examination Devices
 Typical inspection tools for weld
inspection include the following.
b) Bridge cam gauge
 can be used to determine the weld
preparation angle prior to welding.
 This tool can also be used to measure
excess weld metal (reinforcement),
depth of undercut or pitting, fillet
weld throat size or weld leg length
and misalignment (high-low).
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☼ Weld Examination Devices

Typical inspection tools for weld inspection include
the following.
c)
Bridge Fillet weld gauge-The types of fillet weld
gauges include.
1)
Adjustable fillet weld gauge —measures weld sizes for
fit-ups with 45 degree members and welds with unequal
weld leg lengths.
2)
The weld fillet gauge —a quick go/no-go gauge used to
measure the fillet weld leg length. Gauges normally come
in sets with weld leg sizes from 1/8 in. (3 mm) to 1 in.
(25.4 mm). a weld fillet gauge being used to determine if
the crown has acceptable concavity or convexity.
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☼ Weld Examination Devices

Typical inspection tools for weld inspection include the
following.
c)
Digital pyrometer or temperature sensitive crayons
 measures preheat and interpass temperatures.
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 Penetrant examination is a sensitive method of detecting and locating
discontinuities, provided the discontinuities are clear and open to the surface.
 Method
 The method employs a penetrating liquid dye which is applied to the properly cleaned
surface to be examined and which enters the discontinuity.
 After a suitable dwell time, the excess penetrant is removed from the surface and the part is
dried.
 A developer is then applied which acts as a blotter, drawing the penetrant out of the
discontinuity.
 The penetrant, drawn from an opening on the surface, indicates the presence and location
of a discontinuity
Method
Apply Penetrant
Clean then apply Developer
Result
 basic classifications of the penetrant method
There are two basic classifications of the penetrant method, both
using a similar principle.
 One uses a visible dye and the other uses a fluorescent dye which is only visible
with exposure to ultraviolet light.
 Visible penetrant is usually red in color to provide a contrast against the white
developer background. Normal white light is usually sufficient to view the
discontinuities.
 Fluorescent penetrants provide a greenish yellow indication against a dark
background when viewed in a darkened area under a black (ultraviolet) light
source. The fluorescent method is more sensitive due to the fact that the human
eye can more easily discern a fluorescent indication.
Visible dye
PT Types
Fluorescent dye
Three removal systems:
 Solvent
 Water
 Emulsifiable
Solvent removal , Visible dye type
 These Are the Medias by Which They Can Keep
Permanent Records.
 Sketches
 Photographs
 Lift off tapes
 Advantages and Disadvantages
Advantages
Disadvantages
1) Low operator skill level
1) Highly clean metal
2) All materials (Non Porous)
2) Open Surface flaws only
3) Low cost method
3) Somewhat slow
4) Simple equipment
 Application
 Magnetic particle inspection may be applied to detect surface and near surface defects in
ferromagnetic materials only .
 Method
 Clean area to be tested
 Apply contrast paint
 Apply magnetism to the component
 Apply ferromagnetic ink to the component during magnetising
 Interpret the test area
 Post clean and demagnetise (if required)
 Method
Contrast paint
Magnet & Ink
Result
 Magnetic Field Orientation and Flaw Detectability
 If the magnetic field is parallel to the defect, the field will see little disruption
and no flux leakage field will be produced.
 An orientation of 45 to 90 degrees between the magnetic field and the
defect is necessary to form an indication.
 Circumferential Magnetization
 Circular magnetic fields are produced by
1) passing current through the part
2) A headshot on a wet horizontal test unit an
3) Prods
4)Central conductors
 longitudinal Magnetization
 a longitudinal magnetic fields are produced by
1) Permanent magnets and Electromagnetic yokes
2) Coils & Solenoids
Question
?
From the previous slide regarding the optimum test sensitivity, which
kinds of defect are easily found in the images below?
Cracks at 90° to line force will show
Cracks at parallel to line force will not
show
Question
?
From the previous slide regarding the optimum test
sensitivity, which kinds of defect are easily found in the
images below?
Longitudinal (along the axis)
Question
? From the previous slide regarding the optimum test
sensitivity, which kinds of defect are easily found in
the images below?
Longitudinal (along the axis)
Transverse (perpendicular the axis)
 Magnetic Particles
 MT Equipment
 ferromagnetic iron oxides
AC / DC bench units
Dry or wet
AC yokes
 Types
AC / DC yokes
Color dyed
AC / DC prods
Fluorescent
AC / DC coils
 These Are the Medias by Which They Can Keep
Permanent Records.
 Sketches
 Photographs
 Lift off tapes
 Magnetic Particles
Advantages
Disadvantages
1) Low operator skill level
1) Fe Magnetic metal only
2) Rapid
2) De-magnetize may be required
3) Relatively cheap
3) Can cause arc strikes #
4) Portable
4) Poor with thick coatings
# When using the straight current prod technique
 Overview of Radiographic Testing

X or Gamma radiation is imposed upon a test object

Radiation is transmitted to varying degrees dependent upon the density
of the material through which it is travelling

Thinner areas and low density materials show as darker areas on the
radiograph

Thicker areas and High density materials show as lighter areas on a
radiograph

Applicable to metals, non-metals and composites
Method
Load film
Exposure to Radiation
Radioactive source
IQI
Film cassette
Interpret Graph
Developed
Graph
Latent image on the film
 Areas of high radiation transmission, or low absorption, appear as dark areas on the
developed film.
 Areas of low radiation transmission, or high absorption, appear as light areas on the developed
film.
Source
High dense
discontinuity
Low dense
discontinuity
Lighter region
on radiograph
Film
Darker region
on radiograph
Metal Densities
Grams/cubic centimeter
Aluminum
2.70
Steel
7.87
Copper
8.96
Lead
11.34
Tungsten
19.30
Flaw Orientation
Flaw Orientation
0o
10o
20o
Radiographic Techniques
Radiographic Techniques
Radiographic Techniques
Radiographic Techniques
Radiographic Sensitivity ( 2% thickness test object)
 Image Quality Indicators (IQIs) (Penetrameters)
Hole type IQI
Wire type IQI
Radiographic Sensitivity
Placement of IQI
Hole Type IQI
Wire Type IQI
Advantages
Disadvantages
1) A permanent record
1) High operator skill
2) Most materials
2) Difficult interpretation
3) Little surface preparation
3) Requires access to both sides
4) Flaw orientation
5) Safety requirements*
Main Features:

Surface and sub-surface detection

This detection method uses high frequency sound waves, typically above 2MHz to
pass through a material

A probe is used which contains a piezo-electric crystal to transmit and receive
ultrasonic pulses and display the signals on a cathode ray tube or digital display.

a piezo-electric crystal “Refers to materials which can convert electrical energy
to mechanical energy and vice versa.”

For ultrasound to enter a material ,a couplant must be introduced between the probe
and specimen
Method
Apply Couplant
Sound wave
Result*
CRT display
Signal rebounded
from Lack of fusion
Pulse echo
signals
A scan Display
Compression probe
Digital
UT Set,
checking the material ThicknessThickness
 Longitudinal (straight beam)-Compression Probe
 Thickness measurement
Back wall
echo
defect
echo
initial pulse
 Lamination check
Material Thk
defect
0
Compression Probe
10
20
30
40
50
CRT Display
UT Set
A Scan
Display
Angle Probe
 Shear (angle beam) Probe
 Weld check
initial pulse
defect echo
defect
0 10 20 30 40 50
½ Skip
CRT Display
initial pulse
defect echo
defect
Full Skip
0 10 20 30 40 50
CRT Display
UT Advantages
UT Limitations






• Highly skilled operator
• Smooth surfaces
• Groove welds > 1/4” thick
A true volumetric test
One side access
Very accurate
Deep penetration - 200”
Critical flaws found
Equipment fully portable
Eddy Current Testing
“Based on the principle of eddy currents being formed in conductive
materials in the presence of an AC coil and changes in those eddy
currents by material changes.”
Induced Eddy Currents
ET application
 Flaw detection
 Metal thickness
 Coating thickness
 Metal hardness
 Heat treatment
ET Advantages
ET Limitations

No contact required with part

Highly skilled operator

No couplant required

“Too sensitive”

Readily Automated

Shallow penetration - 3/16”

Applicable to all metals

Calibration standards
required

Requires surface cleanliness

Magnetic materials more
difficult
Q-1 When should visual inspection be performed preferably to produce
the most cost effective quality per specification?
A. After Welding
B. When the Foreman Tells You
C. Prior to Welding
D. During Welding
E. A, C and D Above.
Q-2 Which of the following may an inspector use to perform visual
inspection?
(A) magnifying glass
(B) Micrometer
(C) Fillet weld gage
(D) all of the above
(E) Only B and C above
Q-3 which of the following items should inspector check during
welding?
A. Check Preheat and inter-pass temperature
B. Filler metal control and handling
C. Use of welders qualified for specific operations
D. All of The Above
E. Only A and B above
Q-4 which of the following fit-up variables in groove welds is/are
important for an inspector to check before welding?
A. Planar alignment (hi-low)
B. Angular alignment
C. Groove angle
D. All of The Above
E. Only A and B above
Q-5 At which of the following times should the CWI inspect to assure
compliance with the welding procedure?
A. Only During the Qualification Activity
B. Prior To, During and After Production Welding
C. When Requested To By the Welding Foreman
D. Once each Job
E. Approximately Every 6 Months.
Q-6 Which NDT method can be used to detect all of the following :wrong
electrode, excessive travel speed, and /or improper edge preparations?
A. Radiographic
B. Visual
C. Dye Penetrant
D. Hardness
Q-7 What is/are advantage(s) of visual inspection?
A. It is least expensive inspection method
B. Subsurface defects can be found upon completion of welding
C. It allows for detection and correction of many discontinuities before weld
completion
D. All of the above
E. Only A and C above
Q-8 When welds are going to be hidden or inaccessible for inspection in
a finished weldment or structure, they should be inspected ---------.
(A) By barescopic methods to provide access to the hidden welds
(B) After postweld treatment of the completed weldment or structure
(C) Before the start of the welding
(D) During the progress of the assembly as welds are completed
(E) After completion of the work
Q-9 Which of the following occurs when liquid penetrant is applied to
the surface of a test specimen?
(A) flows into discontinuities upon application of developer
(B) is absorbed by discontinuities
(C) is drawn into a discontinuities by capillary action
(D) runs into discontinuities by gravity
(E) penetrates the surface by chemical action
Q-10 Which of the following is an advantage of florescent penetrants
over visible penetrants?
(A) The inspection can be carried out in a well-light area
(B) Small indication are more easily seen because it is more sensitive test
(C) It can be used where contact with water is objectionable
(D) It is less sensitive to contamination of discontinuities.
(E) The visible dye require no vehicle or solvent
Q-11 Liquid penetrant inspection is used for detecting ---------.
(A) weld undercut
(B) excessive weld reinforcement
(C) weld discontinuities open to the surface
(D) short fillet weld leg size
(E) depth of weld penetration
Q-12 Which one of the following conditions will affect the rate and
extent to which a liquid penetrant will enter crack, fissures, and other
small openings?
(A) The hardness of the specimen being tested
(B) The surface condition of the specimen being tested
(C) The color of the penetrant
(D) The conductivity of the specimen being tested
(E) The magnetic field residual in the specimen
Q-13 Which of the following statements is correct regarding magnetic
particle testing?
A. It is sensitive enough to readily detect deep subsurface discontinuities
B. It can be performed on all types of materials, ferrous and non-ferrous
C. Subsurface discontinuities are easily seen and interpreted with this method
D. Subsurface discontinuities near the surface may be observed,but they may not be cleary
defined
E. None of the above
Q-14 During examination of a production weldment the inspector noted
that discontinuity indications found by MT method were not found by
PT method what dose the indicate?
(A) there are no flaws
(B) the discontinuities are all on the surface
(C) the discontinuities size are too small for PT
(D) the discontinuities are not exposed to the surface
(E) none of the above
Q-15 In comparison to surface cracks, the sensitivity of magnetic
particle inspection to flaws1/4 – inch or more below the surface of a
thick.
A. Generally Much Less
B. Approximately Equal
C. Nearly Equal If the Flaws Are Fine Non-Metallic Strings
D. Nearly Equal If the Internal and External Flaws Have Equal Widths
E. Greater If The Flaws Are Located Near The Welds Axis And Ac Current Is
Used.
Q-16 which means is/are best when a permanent record of a
discontinuity discovered by MT is required?.
A. Use clear pressure sensitive tape on the metallic media indication.
B. Take photographs of the metallic media indicating the discontinuity
C. Make a hand drawn sketch from memory
D. Leave the metallic media in place
E. Only A and B above
Q-17 which of the following is needed to obtain maximum detection
capability in the inspection of welds by MT?
A. Use a longitudinal magnetic field
B. Use a circular magnetic field
C. Apply the magnetic field Perpendicular to the weld
D. Apply the magnetic field Direction to the weld
E. Apply the magnetic field in two Directions – 90 Degree a part.
Q-18 Which of the following is/are used to perform MT?
(A) Colored Ferro-magnetic oxide powders
(B) AC and DC articulated leg yokes
(C) DC coils
(D) All of the above
(E) Only A and C above
Q-19 If the prods shown in below figure , which of the following flaws
would cause the clearest indication?
(A) A transverse surface crack
(B) Lack of fusion on the root
(C) A plate lamination
(D) A longitudinal surface crack
(E) A tungsten inclusion
Q-20 the Coil shown in below figure, which of the following flaws would
cause the clearest indication?
(A) A transverse surface crack
(B) Lack of fusion on the root
(C) A plate lamination
(D) A longitudinal surface crack
(E) A tungsten inclusion
Q-21 the yoke shown in below figure, which of the following flaws would
cause the clearest indication?
(A) A transverse surface crack
(B) Lack of fusion on the root
(C) A plate lamination
(D) A longitudinal surface crack
(E) A tungsten inclusion
Q-22 which factor is most important to the reliability of a test ?
A. Ease of Conducting Test
B. Cost of Required Equipment
C. Reproducibility of Test Conditions
D. Speed of Testing
E. Portability of Equipment
Q-23 in film radiography, which of the following are usually used as
image quality indicator (IQIs)?
A. Hole type
B. Step type
C. Wire type
D. Only A and B above
E. Only A and C above
Q-24 Which of the discontinuities is not commonly detected by RT?
A. Undercut
B. Porosity
C. Lamination
D. Slag
Q-25 Which NDT method is suitable and economical for detecting
tungsten inclusion in Aluminum weld ?
A. RT
B. ET
C. PT
D. MT
E. VT
Q-26 In film radiography, IQI s (pentameters) in most instances are
placed to show the quality of the radiograph for the least favorable
geometry. Which of the following answers would be correct for the
placement of the IQI for least favorable geometry?
(A) Between the intensifying screen and the film
(B) On the source side of the test object
(C) On the film side of the test object
(D) Between the operator and the radiation source
(E) At the window of the x-ray tube
Q-27 laminations are best detected by which inspection method?
a. RT
b. UT
c. ET
d. LT
e. AET
Q-28 During examination of a production weldment , The inspector
noted that discontinuity indications found by the UT method were not
found by the PT method. What does that indicate?
A. There are no flaws
B. The discontinuities are all on the Surface
C. The discontinuity sizes are too small for PT Sensitivity.
D. The discontinuity are not open to the Surface
Q-29 An ultrasonic test of a plate shows a trace on the CRT with peaks
as shown in below figure. If the sweep is from left to right, the peak at
(2) may indicate ------.
(A) A flaw at the surface
(B) A flaw near the center
(C) A reflection from the back
(D) A flaw at the back
(E) There is no flaw indicated on the trace