PowerPoint to accompany
Welding
Principles and Practices
Third Edition
Sacks and Bohnart
History of
Welding
Chapter 1
1
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Permission required for reproduction or display.
Overview
• Welding is joining two pieces of metal by:
– Heating to temperature high enough to cause
softening or melting
– With or without application of pressure
– With or without use of filler metal
• Melting point same as metals beginning joined or melting
point below metals but about 800º F
• New methods, applications and systems
– Tremendous progress in short time
• Usually best method to use when fastening metal
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History of Metalworking
• Began when people found they could shape
rocks by chipping them with other rocks
• Copper probably first metal to be worked
– Ductile (easily hammered, bent or drawn)
– In Egypt as early as 4000 B.C. and USA before
2000 B.C.
• Welding began more than 3000 years ago
– Hot or cold metals hammered to obtain forge weld
– Forged metals, bronze and iron mentioned in Old
Testament
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History of Metalworking
• Bronze developed between 3000 and 2000 B.C.
• Iron became known to Europe about 1000 B.C.
– Several thousand years after use of copper
– Philistines had four iron furnaces about 1300 B.C.
• Produced swords, chisels, daggers, and spearheads
– Egyptians began making iron tools during period of
900 to 850 B.C.
– Replaced bronze as metal used in manufacture of
utensils, armor and other applications after 800 B.C.
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History of Metalworking
• Famous Damascus swords and daggers made in
Syria about 1300 B.C.
– Sought because of their strength and toughness
– Made by forge-welding iron bars of different
degrees of hardness, drawing them down, and
repeating process many times
• Working of metals followed one another in
great ancient civilizations
– Copper, bronze, silver, gold, and iron
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History of Metalworking
• Time of Roman Empire
– Iron use common in Europe, Near East and Far East
• Chinese developed ability to make steel from
wrought iron in 589 A.D.
• Belgians responsible for progress with steel in
Europe
• Japan manufactured steel by repeated welding
and forging and controlling amount of carbon
by use of fluxes
– Produced famous Samurai sword
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History of Metalworking
• Blast furnace developed for melting iron about
1000 to 1200 A. D.
• Fourteenth and fifteenth centuries saw great
improvements in design of blast furnaces
• First cast iron cannon produced in early 1600s
• Industrial Revolution in the middle of the
eighteenth century brought many
improvements
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History of Metalworking
• Present factory system of mass production
introduced
– American, Eli Whitney, developed idea of
interchanging parts in manufacture of arms
• Working of dies and molds became
commonplace by beginning of nineteenth
century
• Henry Ford involved in developing assembly
line method for manufacturing automobiles
early in twentieth century
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Early Developments in Welding
• Edmund Davy discovered acetylene at beginning
of nineteenth century
• Sir Humphrey Davy discovered the electric arc
in 1801
– Concerned with use of arc for illumination
These inventions were forerunner of
– Demonstrated possible to maintain high voltage arc
present arc welding process.
for varying periods of time by 1809
• Workable electrical generating devices invented
and developed on practical basis by 1850
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History of Fusion Welding
• First documented instance done by Auguste de
Meritens in 1881
– Welded lead battery plates together with carbon
electrode
• Two of Auguste's pupils, N. Benardos and S.
Olszewski continued work and issued patent
for welding process using carbon electrodes
and electric power source four years later
– Primary goal was repair welding
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Bare Metal Electrode Welding
• Introduced in 1888 by N. G. Slavianoff (Russian)
– Discovery first recognized in western Europe in 1892
• C. L. Coffin was pioneer of welding industry in
United States
– 1889 received patent on equipment and process for
flash-butt welding
– 1890 received additional patents for spot welding
– 1892 received patent for bare metal electrode arc
welding process
• Without knowledge of Slavianoff's work
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History of Metalworking
• Foresche and Picard developed first
commercial oxyacetylene welding torch at turn
of the century
• Electric arc welding method used in US until
about 1920
– Handicapped because of welds produced by these
electrodes not as strong as metal being welded
• Welding arc very unstable
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History of Metalworking
• In 1907 Kjellberg (Swedish engineer) received
patent covering electrode-coating process
– Coating thin and acted only as stabilizer of arc
– Produced welds little better than bare electrodes
• In 1912 Kjellberg received another patent for
electrode with heavier coating made of
asbestos with binder of sodium silicate
• In 1908, Benardos patented electroslag process
of welding thick plates in one pass
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History of Metalworking
• Technology of welding progressed slowly until
World War I
– Demands of war called for improved methods of
fabrication
– End of war, welding widely accepted
• Research on coated electrodes through 1920s
resulted in electrode coatings and improved
core wire
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Multipass Welds
Pass 1
Ability to make multipass welds
such as this one, on plate and pipe,
led to growth of industry. Welds are
sound and have uniform appearance.
Pass 2
Pass 3
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History of Metalworking
• Stick welding process
– Advanced rapidly due to electrode coatings and
improved core wire
– Now called shielded metal arc welding (SMAW)
• X-ray development
– Possible to examine internal soundness of welded
joints
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Shipbuilding
• 5,171 vessels constructed to American Bureau
of Shipping standard
– Through 1945
– During Maritime Commission wartime
shipbuilding program
• Welding was replacing riveting as main method
of assembly
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Development of Modern Welding
• Design of welding machines changed very little
during postwar period
– Done with d.c. current from batteries
• Use of a.c. welding machines occurred in late
1920 and increased in the early 1930s
– First high frequency a.c. industrial machine
introduced in 1936 by Miller Electric Manufacturing
Company
– High rate of metal deposition and absence of arc blow
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Inert Gas Welding
• World War II spurred development
• Possible to produce welds of high purity and
critical application
• Patent issued in 1930 to Hobart and Devers for
use of electric arc within inert gas atmosphere
– Not well received because high cost of argon and
helium and lack of suitable torch equipment
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GTAW Welding
• Tungsten electrode replace magnesium
procedure
– Patent issue in 1942
• Linde Company developed gas tungsten arc
welding (GTAW)
– Also called tungsten inert gas (TIG) process or
HELIARC
– Perfected water-cooled torch capable of high
amperage
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Tungsten Inert Gas (TIG) Process
An aluminum weld made using
the TIG process. The welding
of aluminum is no longer a
problem and can be done with
the same ease as that of steel.
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GTAW Welding
• First done with rotating d.c. welding machines
• Later a.c. units developed
• In 1950s
– Selenium rectifier type d.c. welding machines
– a.c.-d.c. rectifier welding machines with built-in
frequency for GTAW welding became available
• Miller Electric Manufacturing Company
developed Miller controlled-wave a.c. welder
for critical welds on aircraft and missiles
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Development of Modern
Welding (continued)
• Use of aluminum and magnesium increased
– Development of GTAW welding
– Desirable characteristics of reduced weight and
resistance to corrosion
• Thicker materials in construction, which
required preheating using GTAW welding
• U.S. patent issued in 1948 for gas metal arc
welding (GMAW) process
– Superseded earlier terms of metal inert gas (MIG)
and metal active gas (MAG)
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GMAW Process
• Concentrates high heat at a focal point
• Produces
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Small heat-affected zone
Narrow bead width
Deep penetration
Faster welding
speed
Responsible for over
70 percent of welds
being performed today.
• Now used in all
industries
St Louis Car. Co.
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Development of Modern
Welding (continued)
• Rapid changes occurred in 1980s and 1990s
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Exotic multiple gas mixes
State-of-art electrodes
Onboard computers
Robotic welding
• Methods developing that may change way
welds made in future
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Processes Involving
Use of the Electric Arc
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Arc spot welding
Atomic-hydrogen welding
Electrogas
Plasma arc welding
Stud welding
Submerged arc welding
Underwater arc welding
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Specialized Processes Involving
Use of the Electric Arc
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Cold welding
Electron beam welding
Explosive welding
Force welding
Friction welding
Friction stir welding
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Laser welding
Oxyhydrogen welding
Thermit welding
Ultrasonic welding
Welding of plastics
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Industry Demand
• Over 90 welding processes
• Force new and improved developments in
machines, gases, torches, electrodes,
procedures, and technology
• Constant research for new metals done by
shipbuilding, space and nuclear industries
– Spurs research in welding
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Welding Associations
• American National Standards Institute (ANSI)
• American Petroleum Institute (API)
• American Society of Mechanical Engineers
(ASME)
• American Welding Society (AWS)
• American Bureau of Shipping (ABS)
Provide guidance and standards relating
to the welding industry.
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Welding as an Occupation
• Can be certified by AWS, ASME and API
– Tests difficult and require many hours of practice
• Key positions in major industries
– Important to economic welfare of country
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Gender friendly
Done in every civilized country in the world
Offer prestige and security
Chances for advancement excellent
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Industrial Welding Applications
• More than 90 different welding processes
• Divided into three major types
– Arc
– Gas
– Resistance
• Number of other types used to lesser extent
– Induction, forge, thermit, flow, and brazing
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Resistance Welding
• Includes spot welding, seam welding, flash
welding, projection welding, and other similar
processes performed on machines
• Operators usually taught on job
– Semiskilled workers do not need specific hands-onwelding skills
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Arc and Gas Welding
• Focus of this text
• Combine art and science
• Welders have almost complete control of the
process
– Must know properties of metals to weld; which
weld process to use; and how to plan, measure, and
fabricate
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Welding Positions
Overhead
Vertical
General Electric Corp.
As well as flat
and horizontal
Miller Electric Mfg. Co.
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1 - 34
Qualifications and Personal
Characteristics
• Welders certified for ability to do work and
work is inspected
• Required to pass periodic qualification tests
• Certifications issued according to kind and
gauge of metal and specific welding process
• Can hold several different certifications
simultaneously
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Example of Magnetic-Particle
Testing in Building
Weld testing and
inspection give
proof of the
soundness of welds.
Circlesafe Aerosol/Circle Systems, Inc.
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Basic Tasks
• Gas weld
– Attaching proper tip and adjusting welding
regulators for proper volume and gas pressures
• Electric arc welding
– Regulate welding machine for proper welding
current, select proper electrode size and type, and
right shielding gas
• Need steady hand and have good visualization
skills
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Master Welder Job Examples
Welds in these tanks must
meet X-ray requirements
and pass a dye penetrant
test. Tanks are often lined
with a very thin layer of
pure silver.
Nooter Corp
Creating Art!
Enrique Vega
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
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Master Welder
• Master craftsperson
• Able to weld all steels and alloys
– Plus nickel, aluminum, tantalum, titanium,
zirconium, and their alloys and claddings
• Welds of highest quality
• Welds meet requirement of job
– Delicate welding of silver and gold
– Heavy pressure vessels requiring 4-inch plate
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Welding Occupations Requiring
a High School Education
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Welding operator
Welding fitter
Combination welder
Master welder
Welding supervisor
Welding analyst
Inspector
Welding foreman
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Welding superintendent
Equipment sales
Sales demonstrator
Sales troubleshooter
Welding instructor
Robotics welder operator
Jog or fabrication shop
owner
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Welding Occupations Requiring
a College Education
• Welding engineer
(metallurgical)
• Welding development
engineer
• Welding research
engineer
• Welding engineer
• Technical editor
• Welding professor
• Certified welding inspector
(AWS/CWI)
• Corporation executive
• Owner of welding business
• Sales engineer
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Safety and Working Conditions
• Indoors or outdoors
• Noisy
– Hearing protection needed
• Awkward positions
• Spacious surroundings or
cramped quarters
• High off ground in
scaffolds with safety
harness
The Lincoln Electric Corp.
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Job Hazards
• Fire danger
• Burns (including "sunburn" from electric arcs)
• Noxious fumes from materials vaporized at
high temperatures
Hazards can be minimized
• Eyestrain
or eliminated by use
• Welders flash
of proper protective
• Electric shock
clothing and equipment.
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Ways to Stay Current
1. Read trade journals, service manuals,
textbooks, and trade catalogs
2. Join associations such as the American
Welding Society
3. Research topics on the Internet
4. Trade trips with your peers
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