A simple slideshow of common welding process, welding terminology, welding symbols / joint configurations, welder related operations, and welding safety.
This document discusses welding defects and welding processes. It describes various types of welding including arc welding, gas welding, resistance welding, thermit welding, solid state welding, and newer welding techniques. It then discusses common welding defects such as slag inclusion, undercut, porosity, incomplete fusion, overlap, underfill, spatter, excessive convexity/concavity, excessive weld reinforcement, incomplete penetration, and excessive penetration. For each defect it provides the potential causes and recommendations for prevention and repair.
Welding is a fabrication technique that joins materials together by heating them to suitable temperatures using various heat sources like electric arcs or gas flames. There are different types of welding processes categorized by the heat source and filler material used, such as arc welding, gas welding, resistance welding, and solid state welding. The document focuses on three main arc welding processes: shielded metal arc welding uses a consumable electrode covered in flux; gas metal arc welding uses a continuously fed wire electrode and shielding gas; and gas tungsten arc welding uses a non-consumable tungsten electrode and separate shielding gas and filler material. Each process is illustrated and their characteristics are compared. Common welding defects are also briefly discussed.
This document provides an overview of welding including definitions, processes, filler metals, heat sources, protection of the weld pool, advantages, and disadvantages. It discusses how welding joins materials by melting and fusing them together. The key welding processes described are gas welding, arc welding, resistance welding, solid state welding, and others. It also outlines commonly welded base metals and practical applications of welding in industries like aircraft, automotive, ships, and more.
Welding is a process that joins materials by melting them together with heat. There are several common types of welding including stick welding, MIG welding, TIG welding, and flux-cored arc welding. Welding requires certain safety equipment like a face shield, gloves, and protective clothing to avoid burns. Different types of welding rods are used for various materials and situations. Proper equipment is also needed like a welding machine, electrode holders, cables, and accessories. Laser beam and electron beam welding are advanced techniques that use concentrated light sources. Gas welding involves burning fuel gases with oxygen to produce a flame hot enough to melt metals. Forge welding is an ancient solid-state process that joins metals by heating and hammering them
An electrode is a coated metal wire used in welding. There are consumable electrodes that are consumed during welding like in stick welding, and non-consumable electrodes like in TIG welding. The numbers and letters on electrodes indicate properties like tensile strength and position used. Electrodes are classified as basic, cellulosic, rutile, or high iron powder based on coating composition and intended use. Basic electrodes require baking and provide high strength welds. Cellulosic electrodes do not require baking but produce higher hydrogen welds. Rutile electrodes are for general fabrication and baking is optional. Electrodes must be baked if exposed to air beyond specifications to remove moisture.
One of the welding processes that used in Engineering field is the resistance projection welding. There are several types of welding processes similar to this, but resistance projection welding has its unique features.
Thanks for the colleagues who give this slides to publish.
The document discusses various metal joining processes, focusing on welding. It describes different types of welding processes, including arc welding, gas welding, resistance welding, and solid state welding. For arc welding processes specifically, it explains gas metal arc welding (MIG), shielded metal arc welding (SMAW), submerged arc welding (SAW), and the consumable electrodes, shielding gases, and power sources used.
Welding Processes
Two Categories of Welding Processes
Arc Welding
Resistance Welding
Oxy-fuel Gas Welding
Other Fusion Welding Processes
Solid State Welding
Shielded Metal Arc Welding
Gas Metal Arc Welding
Flux‑Cored Arc Welding
Electro gas Welding
Submerged Arc Welding
Gas Tungsten Arc Welding (GTAW) or TIG
Resistant Welding
Brazing and Soldering
The document provides information about welding from a presentation given by Surendra Kumar. It discusses different types of welding including gas welding, arc welding, and their advantages and limitations. Gas welding uses oxygen and acetylene to produce a flame and includes oxy-acetylene welding. Arc welding uses an electric arc between an electrode and base metal to produce heat. Common applications of welding include automobile, aircraft, machinery manufacturing and structural/ship building. In conclusion, welding is widely used in industries to join metals and provides design flexibility at a relatively low cost.
One of the welding processes that used in Engineering field is the TIG welding. There are several types of welding processes similar to this, but tig welding has its unique features.
Thanks for the colleagues who give this slides to publish.
The document provides information on Tungsten Inert Gas (TIG) welding including: the principle of TIG welding where an electric arc is produced between a non-consumable tungsten electrode and the workpiece which is shielded by an inert gas; the main components of a TIG welding torch; factors that influence electrode selection such as diameter and grinding angle; shielding gases like argon and helium; and common applications of TIG welding in industries. Safety precautions for TIG welding are also outlined.
Gas Metal Arc Welding or MIG welding .
Gas metal arc welding (GMAW), sometimes referred to by its subtypes metal inert gas (MIG) welding or metal active gas (MAG) welding, is a welding process in which an electric arc forms between a consumable wire electrode and the workpiece metal(s), which heats the workpiece metal(s), causing them to melt and join
pulsed spray
globular spray
Welding is a process that joins materials by heating them to melt or soften them and allowing them to cool, forming a permanent bond. It is commonly used to join metal parts in manufacturing. Some key types of welding include arc welding, gas welding, resistance welding, and solid state welding. Welding is used in many industries such as automotive, aerospace, shipbuilding, and construction.
GTAW/TIG welding involves an arc between a non-consumable tungsten electrode and the workpiece, with an inert gas shielding the weld area from contamination. It allows for welding of many materials with high quality and precision. The document discusses the equipment, parameters, applications, materials and safety considerations for GTAW welding. It notes the process provides welder control but is also more complex and slower than alternatives like GMAW.
This document provides an overview of welding processes and their principles. It discusses arc welding processes including metallic arc welding, carbon arc welding, and flux shielded metal arc welding. It describes gas welding processes and classifications of welding processes. Key applications of welding are listed across various industries like aircraft construction, automobile construction, bridges, buildings, and more. Advantages and limitations of welding are also summarized.
Electric arc welding involves melting metal parts together at points of contact using an electric arc. It can only join parts made of the same metal. The process requires a workpiece, electrode, electrode holder, cables, welding table, and a power source. Welding should not occur below 25°C or above 70% humidity to prevent cracks and rust. Arc welding is important for infrastructure like pipes, vehicles, electricity towers, and tanks. Successful welding depends on selecting the correct welding current and electrode size for the material thickness, as well as proper travel speed, workpiece preparation, electrode angle, and safety equipment like glasses, ear protection, protective clothing, and ventilation.
This document discusses welding electrodes and welding processes. It provides specifications for AC transformers and DC generators used in welding. It compares AC and DC arc welding, highlighting differences in power consumption, arc stability, electrode types, polarity, suitability for materials, and efficiency. It also compares MIG and TIG welding processes based on electrode type, feed method, current type, feed material, base metal thickness, and welding speed. The document outlines flux coatings used in electrodes and their ingredients for slag formation, arc stabilization, deoxidization, alloying, and binding. It describes coding systems for electrodes and factors to consider when selecting electrodes, such as the power source, base metal composition, thickness, position, current, and desired mechanical
The document provides an overview of various fusion welding processes. It discusses oxyfuel gas welding, arc welding processes using consumable electrodes like shielded metal arc welding and flux-cored arc welding. It also covers non-consumable electrode processes such as electroslag welding, where an arc is started and then heat is produced through electrical resistance in molten slag. Safety practices and equipment used for different welding types like gas metal arc welding are also summarized.
The document discusses various metal joining methods including mechanical fasteners, adhesive bonding, and welding. It focuses on welding, describing what a weld is and different types of welding processes based on heat source, including electric arc welding, gas welding, and others. Specific welding techniques like shielded metal arc welding, oxy-fuel gas welding, and gas metal arc welding are explained in detail, outlining equipment, process parameters, safety considerations, and more. Protective clothing for welders is also reviewed.
The document discusses various manufacturing processes including welding, soldering, and brazing. It describes different welding processes such as gas welding, electric arc welding, and resistance welding. Gas welding uses fuel gases and oxygen to generate heat and join metal pieces. Electric arc welding uses an electric arc to melt metals and can use either AC or DC current. Resistance welding applies pressure and passes a heavy current for a short time to generate heat and join metals. The document provides details on the equipment, parameters, advantages and limitations of the various welding and joining processes.
The document discusses different welding processes and their types. It describes three main types of fusion welding - shielded metal arc welding (SMAW), gas metal arc welding (GMAW), and gas tungsten arc welding (GTAW). SMAW uses a flux-covered electrode to create an arc that melts metal and forms a weld. GMAW uses a continuously fed wire electrode and an inert gas shield. GTAW uses a non-melting tungsten electrode and inert gas shield, allowing for high quality welds. The document compares the different processes and discusses their advantages and disadvantages.
Arc welding processes like shielded metal arc welding, gas metal arc welding and gas tungsten arc welding are described. Shielded metal arc welding uses a consumable electrode covered with a flux to shield the weld. Gas metal arc welding employs a continuously fed wire and shielding gas. Gas tungsten arc welding uses a non-consumable tungsten electrode, shielding gas and a separate filler material. The document discusses welding techniques, processes, defects and includes illustrations of welding joints and processes.
This document provides an overview of various joining processes, including fusion welding processes like gas welding, arc welding, TIG welding, MIG welding, plasma arc welding, and electron beam welding. It also discusses solid-state welding processes and resistance welding processes like spot welding and seam welding. Specific details are provided on plasma arc welding and resistance welding, including their principles, advantages, and applications.
Manufacturing technology I ME 8351 joining process DrPETERPRAKASH
This is very much useful for engineering students, Teachers and industrialist. Adequate knowledge of the concept and principles of welding and welding process used in various industries.
The document discusses advanced welding technologies, including various welding processes such as arc welding, resistance welding, oxyfuel gas welding, and solid state welding. It provides details on common arc welding processes like shielded metal arc welding, gas metal arc welding, flux-cored arc welding, submerged arc welding, and gas tungsten arc welding. The summary discusses the key welding processes, their characteristics, and applications.
The document discusses trends in Tungsten Inert Gas (TIG) welding. It describes TIG welding as a process where an arc is created between a non-consumable tungsten electrode and the workpiece being welded. The weld area is protected by an inert shielding gas. The document outlines factors that influence weld quality such as current, electrode size, filler wire composition, and gas flow rate. It also discusses advantages like precision and disadvantages like lower deposition rates compared to other welding processes. Finally, it presents conclusions that TIG welding produces high-quality welds when performed skillfully and outlines some reference materials.
The document summarizes various welding techniques. It describes the key types of welding including arc welding processes like shielded metal arc welding, gas tungsten arc welding, flux cored arc welding and gas metal arc welding. It also discusses oxy-fuel welding and resistance welding. For each technique, it provides details on the equipment, process and applications as well as advantages and limitations.
The document discusses the different types of arc welding processes. It describes the basic configurations and types of electrodes used in Shielded Metal Arc Welding (SMAW), Gas Metal Arc Welding (MIG), Flux-Cored Arc Welding (FCAW), Submerged Arc Welding (SAW), Gas Tungsten Arc Welding (TIG), Plasma Arc Welding (PAW) and Stud Welding. It also covers the physics behind arc welding including arc plasma formation, arc temperature, arc types, effects of magnetic fields and pulsed DC welding.
Flux-cored arc welding (FCAW) is a semi-automatic welding process that uses a continuously-fed consumable tubular electrode containing a flux along with an arc to produce the weld. Shielding is provided either by gases from the flux inside the electrode or an externally supplied gas. FCAW allows for high welding speeds, is portable, and overcomes restrictions of SMAW. It can be used for both self-shielding without gas or gas-shielding with an external supply, with different advantages for each type.
The welding procedure specification provides direction for welding production joints using the shielded metal arc welding (SMAW) process. It specifies welding double-V groove joints in ASTM SA 516 Grade 70 steel from 4.76 to 50 mm thick using 2.5, 3.15, or 4.0 mm diameter E7018 electrodes. Welding is done in all positions with a preheat of 150°C minimum for thicknesses over 19mm. The procedure qualifies for full penetration groove and fillet welds.
Shielded metal arc welding (SMAW), also known as stick welding, is one of the most popular welding processes. It uses a consumable electrode coated in flux to lay the weld. An electric arc forms between the electrode and workpiece, melting them together. As the weld is laid, the flux protects it from contamination. SMAW is versatile, simple to operate, and widely used in construction and repair. Common quality issues include spatter, porosity, poor fusion, and cracking. Gas metal arc welding (GMAW) is another common process where a continuous wire and shielding gas are fed through a welding gun. It is versatile and preferred for its speed in automotive manufacturing. Quality can be
Demand of welding increase of new materials.
-- ceramics and metal matrix composites.
-- High strength low-alloy (HSLA) steels
Lack of skilled labours
Traditional welding techniques are costly
Safety concerns.
Need to improve the total cost effectiveness of the welding
Lalit Yadav
The document summarizes Saurabh Singla's summer training presentation about welding processes at India Yamaha Motors. It discusses Yamaha's history and describes various welding techniques used at the company like TIG, resistance spot, seam, and MIG welding. Safety equipment for welding and common welding defects are also mentioned. The presentation provides information on welding processes to join metal components in motorcycle exhaust systems and fuel tanks.
Welding is a process that joins materials by heating them to suitable temperatures. There are several types of welding processes, but they can generally be categorized as fusion welding, solid state welding, or a hybrid of the two. Some key welding processes include shielded metal arc welding, gas metal arc welding, gas tungsten arc welding, resistance spot welding, laser beam welding, friction stir welding, and explosion welding. Welding finds applications in many industries for joining similar and dissimilar materials.
The document discusses metal inert gas (MIG) welding. It describes how MIG welding works, the different types of equipment used including wire feeders and torches, parameters that affect the process such as current, voltage, wire size and gas composition. It also covers the different metal transfer modes in MIG welding and common defects that can occur. Penetration is identified as a critical quality parameter that should be around 20% of the workpiece thickness. Penetration can be tested through a penetration test where the weld cross-section is examined after etching.
This document provides information on various welding processes and techniques. It begins by defining welding as joining metals through heat, pressure, or both. It then lists and describes common welding types including arc welding, oxyfuel gas welding, and resistance welding. The document focuses on explaining different arc welding processes such as shielded metal arc welding, submerged arc welding, flux-cored arc welding, gas metal arc welding, gas tungsten arc welding, plasma arc welding, and carbon arc welding. It also provides brief descriptions of oxyfuel gas welding and resistance welding.
An electric vehicle, also called an EV, uses one or more electric motors or traction motors
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Hybrid Electric Vehicle
Plug-in Hybrid Electric Vehicle
Fuel Cell Electric Vehicle
• Electric vehicles will play a pivot role in changing the environment and economy around
the globe in the next two decades.
Metal Inert Gas (MIG)/ Metal Active Gas (MAG) Weldingfaheem maqsood
MIG welding is a process that uses an arc between a consumable electrode wire and the workpiece to produce localized heating and melting. Shielding gas protects the weld from contamination. It allows for high welding speeds and is versatile for both ferrous and non-ferrous metals. MIG welding provides deep penetration, less smoke and fumes compared to other processes. However, it requires complex equipment and parameters to control and the shielding gas adds to the cost.
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ECONOMIC FEASIBILITY AND ENVIRONMENTAL IMPLICATIONS OF PERMEABLE PAVEMENT IN ...Fady M. A Hassouna
Permeable pavement is considered one of the sustainable management
options for roadway networks, which mitigates a number of problems associated with
stormwater, ground water pollution, and traffic safety. In this study, the economic
feasibility, vehicle operation, and environmental implications of implementing permeable
pavement in Nablus, Palestine have been determined by selecting the local roadways that
satisfy the permeable pavement requirement, such as low traffic volume, grade less than
5%, speed limit up to 50 km/h, and subgrade with good permeability. The total costs of
construction and maintenance for both conventional asphalt and permeable pavement have
also been compared based on the life cycle cost analysis (LCCA). Finally, the
environmental implications such as the expected increase in the amount of ground water
and the reduction in water pollutants have been investigated. The results of the analysis
show that the permeable pavement is applicable for the local roadways that have satisfied
the requirements, which are 61 roadways. Furthermore, it could lead to an annual
significant increase in ground water by 107,404.7 m3 and slightly reduce the cost of
construction and maintenance by up to 1,912,000 ILS during its life period compared to
conventional asphalt pavement. Moreover, applying porous asphalt could enhance
vehicular traffic safety by improving skid resistance.
"Operational and Technical Overview of Electric Locomotives at the Kanpur Ele...nanduchaihan9
"My Summer Report" provides a detailed account of the Indian Railways and the operations of electric locomotives at the Electric Loco Shed in Kanpur. It includes information on the history of Indian Railways, the establishment and functioning of the Electric Loco Shed, and technical descriptions of the components and operations of three-phase locomotives. The report discusses various parts of the locomotives such as the pantograph, servo motor, lightening arrester, circuit breaker, main transformer, harmonic filter, traction motor, battery, cooling fan, and compressor. It also explains the working of traction converters and provides circuit diagrams for different locomotive models.
3. Common Welding ProcessesCommon Welding Processes
Listed below are some of the more common welding
processes used :
•SMAW -Shielded Metal Arc Welding (stick)
•GMAW -Gas Metal Arc Welding (mig)
•GTAW -Gas Tungsten Arc Welding (tig)
•SAW -Submerged Arc Welding
4. Common Welding ProcessesCommon Welding Processes
• SMAW- Shielded Metal Arc Welding uses the heat of an
electric arc between a covered metal electrode and the
work (pipe, plate, etc). Shielding comes from the
decomposition of the electrode flux coating. Filler is
supplied by the electrode core wire and covering (iron
powder and alloys).
This process is usually done manually. The basic
equipment is a power source, an electrode holder, a work
clamp and the electrode. Electrodes operate variously on
alternating current, direct current electrode positive
(reverse polarity) or direct current electrode negative
(straight polarity).
5. Common Welding ProcessesCommon Welding Processes
SMAW welding metallurgy
Weld is strengthened by adding alloying elements and by
incorporating iron powder in the electrode
covering(flux). Some ingredients in the covering may
attract and hold moisture (a source of hydrogen) which
causes cracking in certain welds. A group of electrodes
specifically formulated to result in weld deposits having
very low levels of hydrogen are referred to as “Low
Hydrogen” electrodes. These have identification
numbers ending in 5,6 or 8. Once removed from
containers they require electrically heated storage in a
vented oven capable of holding the electrodes between
250 – 350 deg F. (Low hydrogen electrodes should be
stored in their original containers until ready for use)
6. Common Welding ProcessesCommon Welding Processes
SMAW ELECTRODE IDENTIFICATION SYSTEM
Strength- Tensile strength (I.E. 70, or 60) 70,000 psi / 60,000 psi
Position: 1= all positions. 2= flat and horizontal fillet position
only
Example: E-7018, E-6010
7. Common Welding ProcessesCommon Welding Processes
• SMAW limiting factors
All of the welding manipulations are controlled by
the welder, such as electrode inclination, arc length
and travel speed. The welder must set the proper
current and select polarity if direct current.
• Discontinuities
Almost any discontinuity can be produced, but the
most common is porosity, and slag inclusions.
8. Common Welding ProcessesCommon Welding Processes
• GMAW- Gas Metal Arc Welding, sometimes call Mig uses the
heat of an electric arc between a continuous bare wire filler
metal electrode and the work. Shielding is obtained entirely
from an externally supplied inert gas (argon or helium) or
reactive gases (C02 o 02) or a combination thereof. This
process can be semi-automatic or automatic. GMAW process
deposits the weld metal in the joint by one of the following
modes: spray transfer, globular transfer and short circuiting
transfer.
9. Common Welding ProcessesCommon Welding Processes
GMAW MODES
•Spray Transfer – Spray transfer occurs with high current and
voltage combinations. Spray transfer mode best defines the arc
and the pool for the welder. Due to high heat capacity this mode
is best suited for flat and horizontal welding.
•Globular Transfer – Occurs at low currents compared to spray
transfer. Low current at the tip produces large irregular drops
without much direction which results in increased amounts of
spatter compared to spray mode.
10. Common Welding ProcessesCommon Welding Processes
GMAW MODES
•Short Circuiting Transfer (GMAW-S) – The short
circuiting mode is a rather “cold process” and its
misapplication may result in incomplete fusion. It is
mainly used for very light gauge sheet metal welding.
Most refineries and petrochemical plants do not allow
the short circuiting mode of transfer in their welding
specifications to weld on pressure retaining equipment.
11. Common Welding ProcessesCommon Welding Processes
• GMAW Welding Chemistry
Shielded gases protect gas metal arc welds from the
atmosphere. Fluxes are not used in this process. All
deoxidizers and alloying elements are incorporated into the
electrode wire.
• Limiting Factors
The semi-automatic features of gas metal arc welding simplify
the training of the welder and should make work more
consistent, however the short circuiting mode may lead to
incomplete fusion.
13. Common Welding ProcessesCommon Welding Processes
Discontinuities
GMAW may result in any of the common
discontinuities with the exception of slag inclusions.
Porosity which is caused by gas trapped in the weld, is
often the discontinuity found in this process.
Incomplete fusion is possible especially in welds made in
the short circuiting transfer mode.
14. Common Welding ProcessesCommon Welding Processes
GTAW – Gas Tungsten Arc Welding (TIG) uses an
electric arc between a non consumable electrode
(tungsten) and the work. Shielding is obtained from an
inert gas or inert gas mixture. Filler metal is added as
needed. Welds may be made with or without filler
metal as required.
The most significant feature in GTAW is that the
electrode (tungsten) used is not intended to be
consumed. Only the filler metal is consumed
15. Common Welding ProcessesCommon Welding Processes
• Welding Chemistry
The tungsten electrode contributes neither
deoxidation nor fluxing, so it is fortunate that the
melting is essentially slow and that most of the
gases can escape from the weld pool before it
freezes. The filler rod contains the needed
deoxidizers. The slow heating and lower
temperatures combined with slower cooling rates
in GTAW will result in improved weld metal and
heat affected zone mechanical properties.
16. Common Welding ProcessesCommon Welding Processes
• Limiting Factors
The outstanding factor of GTAW is the exceptional
cleanliness that can be obtained in the weld,
producing crack free welds in alloys that are difficult
to weld in other process. However the limiting factor
is the high skill level necessary to produce high
quality welds is acquired by long experience in
manipulating the electrode and feeding the filler
wire when used.
17. Common Welding ProcessesCommon Welding Processes
• Discontinuities
All of the common types of discontinuities are
possible with the exception of slag inclusions.
Porosity is a common discontinuity due to the
processes low tolerance for contamination. Tungsten
inclusions may also result from accidental touching
(dipping ) of tungsten into the molten weld pool.
18. WELDING TERMINOLOGYWELDING TERMINOLOGY
LISTED BELOW IS SOME COMMON WELDING TERMS
• AIR ARC (ARC GOUGE) – The process of removing metal by means of a
carbon arc rod (electrode) connected to a welding machine and air
• BACKWELD – The process of completely welding the one side of a
component, and then back grinding or back gouging the other side and
applying a weld from that side
• BACKING WELD – The process of applying a weld pass to the back side of
the weld to provide a backing. And then completely welding out the
opposite side
• BACKING PLATE OR STRAP – The installation of a plate, strip of plate,
usually of the same material as base metal to the back side of the
weldment to aid in welding up large root openings in a weldment
19. WELDING TERMINOLOGYWELDING TERMINOLOGY
• Cap- The finished portion of the weld (last pass)
• Consumable insert – A type of spacer that is installed in
the root spacing of a pipe or plate to keep the specified
root opening and is made of the same material as the
base metal. This insert acts as the filler metal for the root
and is melted (consumed) with the welding process
normally with GTAW.
• Discontinuity – an imperfection in the weld
• Defect – a discontinuity of sufficient size, length, type that
will render that particular object unsuitable for intended
service base on a criteria in an applicable code
20. WELDING TERMINOLOGYWELDING TERMINOLOGY
• Destructive testing- a sampling of the weld that is actually
taken from the weldment and is subjected to a bend,
tension, or other form of test that usually destroys the
test coupon.
• Essential variables- are those which a change, is
considered to affect the mechanical properties of the
weldment and shall require requalification of the WPS
• Filler metal- The consumable electrode that is used in
most welding processes to fill the weld groove
• Flux- The coating on welding electrodes that when
decomposes during welding forming a shielding gas
around the weld.
21. WELDING TERMINOLOGYWELDING TERMINOLOGY
• Heat Affected Zone (HAZ)- The portion of the base metal that
has not been melted, but whose mechanical properties or
microstructure have been altered by the heat of welding and
cutting
• Preheat- the process of applying heat to a weldment before
welding. This process reduces the thermal gradients within a
weldment and slows down the cooling rates, resulting in a
more ductile structure with lower residual stress. Preheat also
aids in removing moisture and helps remove hydrogen.
22. WELDING TERMINOLOGYWELDING TERMINOLOGY
• Post Weld Heat (PWHT)- also known as stress relieving in
carbon and low alloy steels. The metals temperature is
raised to just below the lower transformation
temperature and held for a prescribed time and allowed
to cool at a controlled rate. This process is done to help
eliminate the residual stress in metals and to reduce the
hardness of the weld and adjacent HAZ after welding to
back within acceptable limits, thereby reducing the
possibility of cracking
• Porosity- a discontinuity in a weld when gas is trapped in
the solidifying metal which is caused by gas released in
the welding process or gas released from chemical
reactions occurring during the welding process.
• Repair – any rework on a completed weld that requires
re-welding to correct a fault discovered by visual or non-
destructive testing and is beyond the standard limits of
acceptability
23. WELDING TERMINOLOGYWELDING TERMINOLOGY
• Root Bead- The first or stringer bead that initially joins
two sections of pipe, plate or fitting
• Welding Procedure Specification (WPS)- a written
procedure (recipe) prepared to provide direction for
making production welds to a code requirement. It is
supported by a PQR (procedure qualification record)
which is a record of actual variables used in the welding of
the test coupon.
• Procedure Qualification Record (PQR) –documentation of
what occurred during welding the test coupon and the
test results of the coupon
25. JOINT CONFIGURATIONJOINT CONFIGURATION
• Root Opening – A separation at the joint root between the
two work pieces
• Root Face – The portion of the groove face adjacent to the
joint root
• Groove Face – The surface of a joint member included in
the groove
• Groove Angle – The total included angle of the groove
between the two work places
• Bevel Angle – The angle formed between the prepared
edge of a member and a plane perpendicular to the
surface of the member
• Groove weld size – The joint penetration of a groove weld
• Plate thickness – The thickness of the base metals to be
welded
30. WELDER RELATEDWELDER RELATED
• A Welder Performance Qualification test is given to
determine the ability of the welder or welding operator to
make sound welds.
• When a welder has not welded with a process for a period
of 6 months or more his qualification shall expire, unless
within the six month period prior to his expiration date,
the welder has welded using a manual or semiautomatic
welding process for that process for which he was
qualified. (Recommend to use a welder continuity sheet)
• Or when there is specific reason to question his ability to
make sound welds.
31. WELDER RELATEDWELDER RELATED
Welder test positions for pipe
•1G- Pipe is horizontal and rotated , welding flat on
or near top of pipe
•2G- Pipe or tube is vertical and not rotated during
welding, welding is horizontal
•5G- Pipe or tube is horizontal fixed, and not
rotatated, weld is vertical, flat and overhead
•6G- Pipe is inclined fixed at a 45 deg angle and
not rotated during welding
33. WELDER RELATEDWELDER RELATED
Welder test positions for plate
•1G- Plate is horizontal weld position is flat
•2G- Plate is vertical axis of weld is horizontal weld
position is horizontal
•3G- Plate is vertical and axis of weld is vertical weld
position is vertical
•4G- Plate is horizontal weld position is overhead
35. WELDER RELATEDWELDER RELATED
Common Discontinuities
• IP- or inadequate penetration without hi-low is defined as
the incomplete filling of the weld root. Inadequate
penetration due to hi-low is the condition that exists
when one edge of the root is exposed or un-bonded
because the adjacent pipe or fitting are misaligned.
• Hi-Low- is the mismatch of either the root or the OD
surface of the pipe, plate or fittings
• Slag Inclusion- is a non metallic solid entrapped in the
weld metal or between the weld metal and parent metal
• Burn Thru- is defined as a portion of the root bead where
excessive penetration has caused the weld puddle to be
blown into the pipe
36. WELDER RELATEDWELDER RELATED
Common Discontinuities cont.
• Concave Root – a root bead that is properly fused to and
completely penetrates the sides of the pipe or plate wall
thickness along both sides but whose center is somewhat
below the the inside surface of the ID wall
• Porosity- can be cluster, wormhole etc. Porosity is entrapped
gas pockets inside the weld
• Undercut- A discontinuity at the edge or toe of the welds
where a groove is created by welding too hot or traveling too
fast during welding.
37. WELDER RELATEDWELDER RELATED
• Tungsten inclusion- is cause when the welder accidentally
dips his tungsten electrode into the weld puddle, and the tip
of the tungsten electrode breaks off and is left un-fused in
the weld metal.
• Incomplete fusion- due to cold lap is defined as an
imperfection between two adjacent weld beads or between
the weld metal and base metal that is not open to the surface
(condition where the two passes or base metal and weld
metal are not fused together)
38. WELDING SAFETYWELDING SAFETY
• SAFETY IS AN IMPORTANT CONSIDERATION IN ALL
WELDING, CUTTING AND RELATED WORK
• THE MOST IMPORTANT COMPONENT OF AN EFFECTIVE WELDING SAFETY
PROGRAM IS LEADERSHIP SUPPORT AND DIRECTION. MANAGEMENT
MUST CLEARLY STATE OBJECTIVES AND SHOW IT’S COMMITMENT TO
WELDING SAFETY
• Management must be certain that only approved welding, cutting,
equipment are used. Such equipment includes torches, regulators,
welding machines, electrode holders, and personal protective devices.
• Proper use and maintenance of the equipment must be taught
• Personnel in areas next to welding and cutting must also be protected
from radiant energy and hot spatter
39. WELDING SAFETYWELDING SAFETY
• Where arc welding or cutting is regularly performed next to painted
walls, the walls should be painted with a finish having a low
reflectivity of ultraviolet rays
• Open flame, electric arcs are a ready source of ignition. The best
protection against fire is to do welding and cutting in specially
designated areas or enclosures made of non combustible materials
• Welding helmets containing the appropriate filter plates must be
used by welders and nearby personnel when viewing an arc.
• Sturdy shoes, boots and heavy clothing should be worn to protect the
body from flying sparks, spatter and radiation burns. (cuff less pants
and covered pockets are recommend
• Durable leather gloves or other suitable material should be worn
• Sparks or hot spatter in the ears can be serious, properly fitted , flame
resistant earplugs should be worn whenever such risk is present
• Ear plugs should be worn when performing air arc gouging
40. WELDING SAFETYWELDING SAFETY
• Personnel should be protected from fumes and gases
performed during welding, cutting etc. Protection from
this exposure is usually accomplished by adequate
ventilation
• Where exposure would exceed permissible limits, with
available ventilation, suitable respiratory protection must
be worn
• Last, do not forget x-ray (gamma ray) radiation safety.
Obey all x-ray barrier signs. Do not go into these areas
when radiography is taking place (normally magenta and
yellow tape)
REMEMBER, WELDING SAFETY IS A VERY IMPORTANT PART
OF WELDING
41. WELDING WRAP UPWELDING WRAP UP
This presentation was only a brief overview of welding,
and was intended to only give a general understanding
and familiarization of some of the more common
processes, safety concerns and terms.
If you have any questions please contact me at
937-418-8489 or Randall@rpsweldingconsultants.com
Thank you for your attendance