Table Of Content1
QUANTUM SERIES
For
B.Tech Students of Third Year
of All Engineering Colleges Affiliated to
Dr. A.P.J. Abdul Kalam Technical University,
Uttar Pradesh, Lucknow
(Formerly Uttar Pradesh Technical University)
Advance Welding
By
Shubham Tyagi
TM
QUANTUM PAGE PVT. LTD.
Ghaziabad New Delhi
2
PUBLISHED BY : Apram Singh
Quantum Publications
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accuracy, however neither the publisher nor the authors
guarantee the accuracy or completeness of any information
published herein, and neither the publisher nor the authors
shall be responsible for any errors, omissions, or damages
arising out of use of this information.
Advance Welding (ME : Sem-5)
1st Edition : 2014-15
2nd Edition : 2015-16
3rd Edition : 2016-17
4th Edition : 2017-18
5th Edition : 2018-19
6th Edition : 2019-20
7th Edition : 2020-21 (Thoroughly Revised Edition)
Price: Rs. 65/- only
Printed Version : e-Book.
3
CONTENTS
KME-055 : ADVANCE WELDING
UNIT-1 : WELDING ARC & POWER SOURCE (1–1H to 1–22H)
Introduction: Introduction to welding, application, classification and process
selection criterion. Health & safety in welding. Welding Arc: Physics of
welding arc, arc initiation, voltage distribution, arc characteristics, arc
efficiency, arc temperatures and arc blow.Mechanism and types of metal
transfer. Welding Power Sources: Types of welding power sources,
operation characteristics and specifications.
UNIT-2 : WELDING PROCESSES (2–1H to 2–44H)
Welding Processes: Shielded Metal Arc Welding (SMAW), Gas Metal Arc
Welding (GMAW) Gas Tungsten Arc Welding (GTAW) Plasma Arc,
Submerged Arc Welding, Electro gas and Electroslag, Resistance welding,
Friction welding, Brazing, Soldering & Braze welding. Laser beam
welding, Electron beam welding, Ultrasonic welding, Explosive welding,
Friction Stir Welding, Underwater welding. Advances in Welding
Processes: Narrow Gap, Tandem (Twin /Multi Wire) Welding, A-TIG,
Hybrid Welding processes, Magnetically impelled arc butt (MIAB)
welding, welding automation and robotic applications.
UNIT-3 : HEAT FLOW WELDING (3–1H to 3–16H)
Heat Flow Welding: Weld thermal cycle, Temperature distribution, Peak
temperature; Heat Affected Zone (HAZ), heating, cooling and solidification
rates. Welding Metallurgy: Fundamentals of physical metallurgy, Principle
of solidification of weld metal, Reactions in weld pool - Gas metal reaction,
Slag metal reaction, factors affecting changes in microstructure and mechanical
properties of HAZ, Micro and macro structures in weld metal and HAZ.
UNIT-4 : REPAIR & MAINTENANCE WELDING (4–1H to 4–17H)
Repair & Maintenance Welding: Hardfacing, Cladding, Surfacing,
Metallizing processes and Reclamation welding. Weldability: Effects of
alloying elements on weldability, carbon equivalent, welding of plain
carbon steel, Stainless steel, Cast Iron and Aluminium alloys, Welding of
Dissimilar Materials.
UNIT-5 : WELD DESIGN & WELDING CODES (5–1H to 5–35H)
Weld Design: Types of welds & joints, Welding Symbols, Weld defects
and Remedies, Residual Stresses & Distortion, Inspection and testing of
welds: Introduction to Non Destructive Techniques; Destructive Techniques
- Bulk and Microhardness test, Wear test and types, corrosion test, tensile
test, bend test, SEM, EDS and XRD. Welding Codes, WPS & PQR:
Introduction to welding codes, ISO, ASME and BIS specifications, Welding
Procedure Specification (WPS) & Procedure Qualification Record (PQR),
Welding of pipe lines and pressure vessels.
SHORT QUESTIONS (SQ-1 H to SQ-13 H)
SOLVED PAPERS (2016-17 TO 2018-19) (SP-1 H to SP-10 H)
MECHANICAL(cid:3)ENGINEERING(cid:1)
(cid:3)
Semester(cid:3)–(cid:3)V:(cid:3)Departmental(cid:3)Elective(cid:3)–(cid:3)II:(cid:3)Specialization(cid:3)–(cid:3)Manufacturing(cid:3)and(cid:3)Automation(cid:3)
Subject(cid:3)Code:(cid:3)KME(cid:3)055(cid:3) Advance(cid:3)welding(cid:3) L(cid:3)T(cid:3)P(cid:3):(cid:3)3(cid:3)0(cid:3)0(cid:3) Credits:(cid:3)3(cid:3)
(cid:3)
Bloom(cid:3)
Course(cid:3)Outcome:(cid:3)Student(cid:3)will(cid:3)be(cid:3)able(cid:3)to(cid:3)
Taxonomy(cid:3)
Understand(cid:3)the(cid:3)physics(cid:3)of(cid:3)arc(cid:3)welding(cid:3)process(cid:3)and(cid:3)various(cid:3)operating(cid:3)characteristics(cid:3)
CO(cid:3)1(cid:3) K2(cid:3)
of(cid:3)welding(cid:3)power(cid:3)source.(cid:3)
CO(cid:3)2(cid:3) Analyse(cid:3)various(cid:3)welding(cid:3)processes(cid:3)and(cid:3)their(cid:3)applications.(cid:3) K3(cid:3)
Apply(cid:3)the(cid:3)knowledge(cid:3)of(cid:3)welding(cid:3)for(cid:3)repair(cid:3)&(cid:3)maintenance,(cid:3)along(cid:3)with(cid:3)the(cid:3)
CO(cid:3)3(cid:3) K3(cid:3)
weldability(cid:3)of(cid:3)different(cid:3)materials.(cid:3)
Apply(cid:3)the(cid:3)concept(cid:3)of(cid:3)quality(cid:3)control(cid:3)and(cid:3)testing(cid:3)of(cid:3)weldments(cid:3)in(cid:3)industrial(cid:3)
CO(cid:3)4(cid:3) K3(cid:3)
environment.(cid:3)
CO(cid:3)5(cid:3) Evaluate(cid:3)heat(cid:3)flow(cid:3)in(cid:3)welding(cid:3)and(cid:3)physical(cid:3)metallurgy(cid:3)of(cid:3)weldments.(cid:3) K4(cid:3)
(cid:3)
UNIT(cid:882)I:(cid:3)
Introduction:(cid:3)Introduction(cid:3)to(cid:3)welding,(cid:3)application,(cid:3)classification(cid:3)and(cid:3)process(cid:3)selection(cid:3)criterion.(cid:3)Health(cid:3)
&(cid:3)safety(cid:3)in(cid:3)welding.(cid:3)
(cid:3)
Welding(cid:3)Arc:(cid:3)Physics(cid:3)of(cid:3)welding(cid:3)arc,(cid:3)arc(cid:3)initiation,(cid:3)voltage(cid:3)distribution,(cid:3)arc(cid:3)characteristics,(cid:3)arc(cid:3)efficiency,(cid:3)
arc(cid:3)temperatures(cid:3)and(cid:3)arc(cid:3)blow.Mechanism(cid:3)and(cid:3)types(cid:3)of(cid:3)metal(cid:3)transfer.(cid:3)
(cid:3)
Welding(cid:3)Power(cid:3)Sources:(cid:3)Types(cid:3)of(cid:3)welding(cid:3)power(cid:3)sources,(cid:3)operation(cid:3)characteristics(cid:3)and(cid:3)specifications.(cid:3)(cid:3)
(cid:3)
UNIT(cid:882)II:(cid:3)
Welding(cid:3)Processes:(cid:3)Shielded(cid:3)Metal(cid:3)Arc(cid:3)Welding(cid:3)(SMAW),(cid:3)Gas(cid:3)Metal(cid:3)Arc(cid:3)Welding(cid:3)(GMAW)(cid:3)Gas(cid:3)Tungsten(cid:3)
Arc(cid:3) Welding(cid:3) (GTAW)(cid:3) Plasma(cid:3) Arc,(cid:3) Submerged(cid:3) Arc(cid:3) Welding,(cid:3) Electro(cid:3) gas(cid:3) and(cid:3) Electroslag,(cid:3) Resistance(cid:3)
welding,(cid:3)Friction(cid:3)welding,(cid:3)Brazing,(cid:3)Soldering(cid:3)&(cid:3)Braze(cid:3)welding.(cid:3)Laser(cid:3)beam(cid:3)welding,(cid:3)Electron(cid:3)beam(cid:3)
welding,(cid:3)Ultrasonic(cid:3)welding,(cid:3)Explosive(cid:3)welding,(cid:3)Friction(cid:3)Stir(cid:3)Welding,(cid:3)Underwater(cid:3)welding.(cid:3)
(cid:3)
Advances(cid:3)in(cid:3)Welding(cid:3)Processes:(cid:3)Narrow(cid:3)Gap,(cid:3)Tandem(cid:3)(Twin(cid:3)/(cid:3)Multi(cid:3)Wire)(cid:3)Welding,(cid:3)A(cid:882)TIG,(cid:3)Hybrid(cid:3)
Welding(cid:3)processes,(cid:3)Magnetically(cid:3)impelled(cid:3)arc(cid:3)butt(cid:3)(MIAB)(cid:3)welding,(cid:3)welding(cid:3)automation(cid:3)and(cid:3)robotic(cid:3)
applications.(cid:3)
(cid:3)
UNIT(cid:882)III:(cid:3)
Heat(cid:3)Flow(cid:3)Welding:(cid:3)Weld(cid:3)thermal(cid:3)cycle,(cid:3)Temperature(cid:3)distribution,(cid:3)Peak(cid:3)temperature;(cid:3)Heat(cid:3)Affected(cid:3)
Zone(cid:3)(HAZ),(cid:3)heating,(cid:3)cooling(cid:3)and(cid:3)solidification(cid:3)rates.(cid:3)(cid:3)
(cid:3)
Welding(cid:3)Metallurgy:(cid:3)Fundamentals(cid:3)of(cid:3)physical(cid:3)metallurgy,(cid:3)Principle(cid:3)of(cid:3)solidification(cid:3)of(cid:3)weld(cid:3)metal,(cid:3)
Reactions(cid:3) in(cid:3) weld(cid:3) pool(cid:3) (cid:882)(cid:3) Gas(cid:3) metal(cid:3) reaction,(cid:3) Slag(cid:3) metal(cid:3) reaction,(cid:3) factors(cid:3) affecting(cid:3) changes(cid:3) in(cid:3)
microstructure(cid:3)and(cid:3)mechanical(cid:3)properties(cid:3)of(cid:3)HAZ,(cid:3)Micro(cid:3)and(cid:3)macro(cid:3)structures(cid:3)in(cid:3)weld(cid:3)metal(cid:3)and(cid:3)HAZ(cid:3)(cid:3)
(cid:3)
UNIT(cid:882)IV:(cid:3)
Repair(cid:3)&(cid:3)Maintenance(cid:3)Welding:(cid:3)Hardfacing,(cid:3)Cladding,(cid:3)Surfacing,(cid:3)Metallizing(cid:3)processes(cid:3)and(cid:3)Reclamation(cid:3)
welding.(cid:3)
(cid:3)
Curriculum(cid:3)&(cid:3)Evaluation(cid:3)Scheme(cid:3)V(cid:3)&(cid:3)VI(cid:3)semester(cid:3)(cid:3) Page(cid:3)26(cid:3)
(cid:3)
MECHANICAL(cid:3)ENGINEERING(cid:1)
(cid:3)
Weldability:(cid:3)Effects(cid:3)of(cid:3)alloying(cid:3)elements(cid:3)on(cid:3)weldability,(cid:3)carbon(cid:3)equivalent,(cid:3)welding(cid:3)of(cid:3)plain(cid:3)carbon(cid:3)
steel,(cid:3)Stainless(cid:3)steel,(cid:3)Cast(cid:3)Iron(cid:3)and(cid:3)Aluminium(cid:3)alloys,(cid:3)Welding(cid:3)of(cid:3)Dissimilar(cid:3)Materials(cid:3)(cid:3)
(cid:3)
UNIT(cid:882)V:(cid:3)
Weld(cid:3)Design:(cid:3)Types(cid:3)of(cid:3)welds(cid:3)&(cid:3)joints,(cid:3)Welding(cid:3)Symbols,(cid:3)Weld(cid:3)defects(cid:3)and(cid:3)Remedies,(cid:3)Residual(cid:3)Stresses(cid:3)
&(cid:3)Distortion,(cid:3)Inspection(cid:3)and(cid:3)testing(cid:3)of(cid:3)welds:(cid:3)Introduction(cid:3)to(cid:3)Non(cid:3)Destructive(cid:3)Techniques;(cid:3)Destructive(cid:3)
Techniques(cid:3)(cid:882)(cid:3)Bulk(cid:3)and(cid:3)Microhardness(cid:3)test,(cid:3)Wear(cid:3)test(cid:3)and(cid:3)types,(cid:3)corrosion(cid:3)test,(cid:3)tensile(cid:3)test,(cid:3)bend(cid:3)test,(cid:3)
SEM,(cid:3)EDS(cid:3)and(cid:3)XRD.(cid:3)
(cid:3)
Welding(cid:3)Codes,(cid:3)WPS(cid:3)&(cid:3)PQR:(cid:3)Introduction(cid:3)to(cid:3)welding(cid:3)codes,(cid:3)ISO,(cid:3)ASME(cid:3)and(cid:3)BIS(cid:3)specifications,(cid:3)Welding(cid:3)
Procedure(cid:3) Specification(cid:3) (WPS)(cid:3) &(cid:3) Procedure(cid:3) Qualification(cid:3) Record(cid:3) (PQR),(cid:3) Welding(cid:3) of(cid:3) pipe(cid:882)lines(cid:3) and(cid:3)
pressure(cid:3)vessels.(cid:3)
(cid:3)
Books(cid:3)and(cid:3)References:(cid:3)
1. Welding(cid:3)and(cid:3)Welding(cid:3)Technology,(cid:3)by(cid:882)(cid:3)Richard(cid:3)L.(cid:3)Little,(cid:3)McGraw(cid:3)Hill(cid:3)Education.(cid:3)
2. Welding(cid:3)Principals(cid:3)and(cid:3)Practices,(cid:3)by(cid:882)(cid:3)Edwars(cid:3)R.(cid:3)Bohnart,(cid:3)McGraw(cid:3)Hill(cid:3)Education.(cid:3)
3. Welding(cid:3)Engineering(cid:3)and(cid:3)Technology,(cid:3)by(cid:882)(cid:3)R.(cid:3)S.(cid:3)Parmar,(cid:3)KhannaPublishsers.(cid:3)
4. Welding(cid:3)Technology(cid:3)Fundamentals(cid:3)by(cid:3)William.(cid:3)A.(cid:3)Bowditch.(cid:3)
5. Welding(cid:3)Technology(cid:3)by(cid:3)N(cid:3)K(cid:3)Srinivasan.(cid:3)
6. Welding(cid:3)Engineering(cid:3)and(cid:3)Technology(cid:3)by(cid:3)R(cid:3)S(cid:3)Parmar.(cid:3)
7. Modern(cid:3)Welding(cid:3)Technology(cid:3)by(cid:3)Howard(cid:3)B(cid:3)Cary(cid:3)and(cid:3)Scott(cid:3)Helzer.(cid:3)
8. Welding(cid:3)Handbooks(cid:3)(Vol.(cid:3)I(cid:3)&(cid:3)II)(cid:3)
9. Advanced(cid:3)Welding(cid:3)Processes,(cid:3)Woodhead(cid:3)publishing,(cid:3)J.(cid:3)Norrish(cid:3)
10. ASME(cid:3)Sec.(cid:3)IX,(cid:3)Boiler(cid:3)and(cid:3)Pressure(cid:3)Vessel(cid:3)Code(cid:3)
(cid:3) (cid:3)
Curriculum(cid:3)&(cid:3)Evaluation(cid:3)Scheme(cid:3)V(cid:3)&(cid:3)VI(cid:3)semester(cid:3)(cid:3) Page(cid:3)27(cid:3)
(cid:3)
Advance Welding 1–1 H (ME-Sem-5)
1
Welding Arc and
Power Sources
CONTENTS
Part-1 : Introduction : Introduction..................... 1–2H to 1–7H
to Welding, Application,
Classification and
Process Selection Criterion
Part-2 : Health and Safety in Welding................ 1–7H to 1–8H
Part-3 : Welding Arc : Physics of........................ 1–8H to 1–10H
Welding Arc, Arc
Initiation, Voltage Distribution
Part-4 : Arc Characteristics, Arc ...................... 1–10H to 1–15H
Efficiency, Arc Temperatures
and Arc Blow
Part-5 : Mechanism and Types of..................... 1–15H to 1–16H
Metal Transfer
Part-6 : Welding Power Sources :.................... 1–16H to 1–21H
Types of Welding Power
Sources, Operation
Characteristics and Specifications
Welding Arc & Power Sources 1–2 H (ME-Sem-5)
PART-1
Introduction : Introduction to Welding, Application,
Classification and Process Selection Criterion.
Questions-Answers
Long Answer Type and Medium Answer Type Questions
Que 1.1. What is welding ? Explain the importance of welding.
Answer
A. Welding :
1. The term welding is used to cover a wide range of bonding techniques.
2. It is defined as a localized coalescence of metals, wherein coalescence is
obtained by heating to suitable temperature with or without the
application of pressure and with or without use of filler metal. The filler
metal has a melting point approximately the same as base metal.
3. A good welded joint is as strong as the parent metal. The product is
known as weldment.
B. Importance of Welding :
1. The welding process is readily adaptable to stream line structure and
the welded joints are very tight.
2. Welded joints are strong, especially under static loading. However, they
have poor fatigue resistance due to stress concentration, residual stresses
and various weld defects, such as cracks, incomplete fusion, slag
inclusion. But all these drawbacks can be overcome to a large extent.
3. Now a days many processes of welding have been developed and probably
there is no industry which is not using welding process in the fabrication
of its products in some form or the other.
4. Welding is most rapid and easiest way of fabrication and assembly of
metal parts.
5. Welding is extensively used in the following fields : automobiles industry,
aircraft machine frames, structural work, tanks, machine repair work,
ship building, and refineries, fabrication of metal structures.
Que 1.2. What are the advantages and limitations of welding ?
Advance Welding 1–3 H (ME-Sem-5)
Answer
A. Advantages of Welding :
1. Welding results in a good saving of material and reduced labour content
of production.
2. Low manufacturing costs.
3. It gives the designer great latitude in planning and designing.
4. Welding is also useful as a method for repairing broken or defective
metal parts.
5. Without welding techniques, the light weight methods of fabrication, so
vital to the automotive and aircraft industries, would be unthinkable.
6. Welding joint is as stronger as base metal and its efficiency is upto 100 %.
7. Alteration and amendment is possible in existing structure by welding
joint.
B. Limitations of Welding :
1. Special jigs and fixtures are required for welding.
2. Edge preparation is required before welding which is time and labour
consuming process.
3. Skilled person is needed for welding purpose.
4. Ultraviolet rays and infrared rays generated during the welding process
are harmful for operator’s skin as well as for eyes.
5. Welding heat produces metallurgical changes in workpiece.
6. During welding, thermal stresses developed in the workpiece, heat
treatment processes are required to relieve the thermal stresses.
Que 1.3. What are the applications of welding ? Give in detail.
Answer
Applications of welding are as follows :
i. Automobile and Transport Industries :
1. Wherein cars, trucks, jeeps and many other transportation machines
and equipments are fabricated.
ii. Building Construction Industries :
1. Welding is greatly used in building industries for joining frames of doors
and windows, reinforcement in concrete works, railings and staircases.
2. When building is a steel frame construction comprising of steel roofing
frames covered with asbestos sheets or galvanized iron sheet, welding
has still greater role to play in joining the structural components for
joining building, frames and trusses.
