Chapter II – Metallurgy and Shielded Metal Arc
Welding( SMAW)
Specific Objectives:
After reading Chapter II, students should be able to:
1.
2.
3.
4.
Have an overview of the Metallurgy.
Discuss Two (2) kinds of metals.
Discuss Characteristics/Properties and uses of the different metals.
Have an overview of Shielded Metal Arc Welding( SMAW)
Metallurgy - Definition & Processes
What is Metallurgy?
Metallurgy is defined as a process that is used for the extraction of metals in their
pure form. The compounds of metals mixed with soil, limestone, sand, and rocks are known
as minerals. Metals are commercially extracted from minerals at low cost and minimum
effort. These minerals are known as ores. A substance which is added to the charge in the
furnace to remove the gangue (impurities) is known as flux. Metallurgy deals with the
process of purification of metals and the formation of alloys.
Steps in Metallurgical Process
The various processes involved in extracting metals from their ores and refining them for use
are referred to as metallurgy.
The following are the various steps in the metal extraction or metallurgical process:

Crushing and grinding the ore.

The concentration of ore, is also known as ore enrichment.

Metal extraction from concentrated ore.

Impure metals are refined or purified.
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Copper Flash Smelting Process
Principles of Metallurgy:
The metallurgical process can be classified as the following:
1. Crushing and grinding: The first process in metallurgy is crushing of ores into a fine
powder in a crusher or ball mill. This process is known as pulverization.
2. The concentration of ores: The process of removing impurities from ore is known as a
concentration of minerals or ore dressing. In metallurgy, we concentrate the ores mainly by
the following methods.
3. Hydrolytic method: In this method, we pour the ore over a sloping, vibrating corrugated
table with grooves. A jet of water is allowed to flow over the surface. The denser ore particles
settle in the grooves, and the impurities are washed away by water.
4. Magnetic separation: In this case, the crushed ore is placed on a conveyor belt. This belt
rotates around two wheels in which one of the wheels is magnetic, and therefore the magnetic
particles get attracted to the magnetic wheel and fall apart from the non-magnetic particles.
5. Froth floatation: In this process, we take the crushed ore in a large tank which contains
oil and water. A current of compressed air is passed through it. The ore gets wet by oil and is
separated from the impurities in the form of froth. Ore is lighter, and so it comes on the
surface and impurities are left behind.
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6. Roasting and calcination: In metallurgy, the process of heating a concentrated ore in the
presence of oxygen is known as roasting. This process is applied in the case of sulfide ores.
For ores containing carbonate or hydrated oxides, heating is done in the absence of air to melt
the ores, and this process is known as calcination.
The Difference Between Ferrous and Non-Ferrous Metal
Category: Metal Man Knows, VideoPosted: September 23, 2015
What’s The Difference Between Ferrous and Non-Ferrous Metal?
The simple answer is that ferrous metals contain iron and non-ferrous metals do not.
The more in-depth answer is that ferrous metals and non-ferrous metals each have their own
distinctive properties. These properties determine the applications they are most suited for.
Non-ferrous metals have been used since the beginning of civilization. The discovery
of copper in 5,000 BC marked the end of the Stone Age and the beginning of the Copper Age.
The later invention of bronze, an alloy of copper and tin, started the Bronze Age.
The use of ferrous metals started in around 1,200 BC when iron production started to
become commonplace. This ushered in the Iron Age.
Which Metals Are Ferrous?
Some common ferrous metals include alloy steel, carbon steel, cast iron and wrought
iron. These metals are prized for their tensile strength and durability. Carbon Steel – also
known as structure steel – is a staple in the construction industry and is used in the tallest
skyscrapers and longest bridges. Ferrous metals are also used in shipping containers,
industrial piping, automobiles, railroad tracks, and many commercial and domestic tools.
Ferrous metals have a high carbon content which generally makes them vulnerable to
rust when exposed to moisture. There are two exceptions to this rule: wrought iron resists rust
due to its purity and stainless steel is protected from rust by the presence of chromium.
Most ferrous metals are magnetic which makes them very useful for motor and
electrical applications. The use of ferrous metals in your refrigerator door allows you to pin
your shopping list on it with a magnet.
Steel
Steel is made by adding iron to carbon which hardens the iron. Alloy steel becomes
even tougher as other elements like chromium and nickel are introduced. Steel is made by
heating and melting iron ore in furnaces. The steel can is tapped from the furnaces and
poured into molds to form steel bars. Steel is widely used in the construction and
manufacturing industries.
Carbon Steel
Carbon steel has a higher carbon content in comparison to other types of steel making
it exceptionally hard. It is commonly used in the manufacturing of machine tools, drills,
blades, taps, and springs. It can keep a sharp cutting edge.
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Alloy Steel
Alloy steels incorporate elements such as chromium, nickel and titanium to impart
greater strength and durability without increasing weight. Stainless steel is an important alloy
steel made using chromium. Alloy steels are used in construction, machine tools, and
electrical components.
Cast Iron
Cast iron is an alloy made from iron, carbon, and silicon. Cast iron is brittle and hard
and resistant to wear. It’s used in water pipes, machine tools, automobile engines and stoves.
Wrought Iron
Wrought iron is an alloy with so little carbon content it’s almost pure iron. During the
manufacturing process, some slag is added which gives wrought iron excellent resistance to
corrosion and oxidation, however, it is low in hardness and fatigue strength. Wrought iron is
used for fencing and railings, agricultural implements, nails, barbed wire, chains, and various
ornaments.
Which Metals Are Non-Ferrous?
Non-ferrous metals include aluminum, copper, lead, zinc and tin, as well as precious
metals like gold and silver. Their main advantage over ferrous materials is their malleability.
They also have no iron content, giving them a higher resistance to rust and corrosion, and
making them ideal for gutters, liquid pipes, roofing and outdoor signs. Lastly they are nonmagnetic, which is important for many electronic and wiring applications.
Aluminum
Aluminum is lightweight, soft and low strength. Aluminum is easily cast, forged,
machined and welded. It’s not suitable for high-temperature environments. Because
aluminum is lightweight, it is a good choice for the manufacturing of aircraft and food cans.
Aluminum is also used in castings, pistons, railways, cars, and kitchen utensils.
Copper
Copper is red in color, highly ductile, malleable and has high conductivity for
electricity and heat. Copper is principally used in the electrical industry in the form of wire
and other conductors. It’s also used in sheet roofing, cartridge cases, statutes, and bearings.
Copper is also used to make brass, an alloy of copper and zinc.
Lead
Lead is a soft, heavy, malleable metal with a low melting point and low tensile
strength. It can withstand corrosion from moisture and many acids. Lead is widely used in
electrical power cables, batteries, building construction and soldering.
Zinc
Zinc is a medium to low strength metal with a very low melting point. It can be
machined easily, but heating may be required to avoid cleavage of crystals. Zinc is most
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widely used in galvanizing, the process of applying a protective zinc coating to iron or steel
to prevent rust.
Tin
Tin is very soft and malleable, ductile with low tensile strength. It’s often used to coat
steel to prevent corrosion. Tinplate steel is used to make tin cans to hold food. In the late 19th
century, tin foil was commonly used to wrap food products, but has since largely been
replaced by aluminum foil. Tin can also be alloyed with copper to produce tin brass and
bronze.
Properties of Metals
An element is a substance made up of one kind of atom; it cannot be separated into
simpler parts. For example, the element helium (think hot-air balloons) is made up
exclusively of helium atoms.
Elements are generally classified as metals or nonmetals (although some elements have
characteristics of both; these are called metalloids).
Three properties of metals are:
Luster: Metals are shiny when cut, scratched, or polished.
Malleability: Metals are strong but malleable, which means that they can be easily bent
or shaped. For centuries, smiths have been able to shape metal objects by heating metal and
pounding it with a hammer. If they tried this with nonmetals, the material would shatter!
Most metals are also ductile, which means they can be drawn out to make wire.
Conductivity: Metals are excellent conductors of electricity and heat. Because they are
also ductile, they are ideal for electrical wiring. (You can test this using some household
items. Keep reading to find out how!)
Additional Properties of Metals
High melting point: Most metals have high melting points and all except mercury are solid
at room temperature.
Sonorous: Metals often make a ringing sound when hit.
Reactivity: Some metals will undergo a chemical change (reaction), by themselves or with
other elements, and release energy. These metals are never found in a pure form, and are
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difficult to separate from the minerals they are found in. Potassium and sodium are the most
reactive metals. They react violently with air and water; potassium will ignite on contact with
water!
Other metals don’t react at all with other metals. This means they can be found in a
pure form (examples are gold and platinum). Because copper is relatively inexpensive and
has a low reactivity, it’s useful for making pipes and wiring.
Five groups of metals:
1. Noble Metals are found as pure metals because they are nonreactive and don’t
combine with other elements to form compounds. Because they are so nonreactive,
they don’t corrode easily. This makes them ideal for jewelry and coins. Noble metals
include copper, palladium, silver, platinum, and gold.
2. Alkali Metals are very reactive. They have low melting points and are soft enough
to be cut with a knife. Potassium and sodium are two alkali metals.
3. Alkaline Earth Metals are found in compounds with many different minerals.
They are less reactive than alkali metals, as well as harder, and have higher melting
points. This group includes calcium, magnesium, and barium.
4. Transition Metals are what we usually think of when we think of metals. They are
hard and shiny, strong, and easy to shape. They are used for many industrial purposes.
This group includes iron, gold, silver, chromium, nickel, and copper, some of which
are also noble metals.
5. Poor Metals are fairly soft, and most are not used very much by themselves. They
become very useful when added to other substances, though. Poor metals include
aluminum, gallium, tin, thallium, antimony, and bismuth.
Alloys: Strong Combinations
The properties of these different metals can be combined by mixing two or more of
them together. The resulting substance is called an alloy. Some of our most useful building
materials are actually alloys. Steel, for example, is a mixture of iron and small amounts of
carbon and other elements; a combination that is both strong and easy to use. (Add chromium
and you get stainless steel. Check your kitchen pots and pans to see how many are made from
stainless steel!)
Other alloys like brass (copper and zinc) and bronze (copper and tin) are easy to shape
and beautiful to look at. Bronze is also used frequently in ship-building because it is resistant
to corrosion from sea water.
Titanium is much lighter and less dense than steel, but as strong; and although heavier
than aluminum, it’s also twice as strong. It’s also very resistant to corrosion. All these factors
make it an excellent alloy material. Titanium alloys are used in aircraft, ships, and spacecraft,
as well as paints, bicycles, and even laptop computers!
Gold, as a pure metal, is so soft that it is always mixed with another metal (usually
silver, copper, or zinc) when it’s made into jewelry. The purity of gold is measured in karats.
The purest you can get in jewelry is 24 karats, which is about 99.7% pure gold. Gold can also
be mixed with other metals to change its color; white gold, which is popular for jewelry, is an
alloy of gold and platinum or palladium.
Metal from Ore
Ores are rocks or minerals from which a valuable substance – usually metal – can be
extracted. Some common ores include galena (lead ore), bornite and malachite (copper),
cinnabar (mercury), and bauxite (aluminum). The most common iron ores are magnetite and
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hematite (a rusty-colored mineral formed by iron and oxygen), which both contain about 70%
iron.
There are several processes for refining iron from ore. The older process is to burn
iron ore with charcoal (carbon) and oxygen provided by bellows. The carbon and oxygen,
including the oxygen in the ore, combine and leave the iron. However, the iron does not get
hot enough to melt completely and it contains silicates left over from the ore. It can be heated
and hammered out to form wrought iron.
The more modern process uses a blast furnace to heat iron ore, limestone, and coke
(a coal product, not the soft drink). The resulting reactions separate out the iron from the
oxygen in the ore. This ‘pig iron’ needs to be further mixed to create wrought iron. It can also
be used for another important purpose: when heated with carbon and other elements, it
becomes a stronger metal called steel.
Considering the process involved, it’s not surprising that iron was not used until
around 1500 BC. But some pure metals – gold, silver, and copper – were used before then,
and the alloy bronze is thought to have been discovered by the Sumerians around 3500 BC.
But aluminum, one of the most essential metals in modern use, wasn’t discovered until AD
1825, and wasn’t commonly used until the 20th century!
Corrosion: Process & Prevention
Have you ever seen a piece of silver that lost its shine, or iron with reddish-colored
rust on it or even holes in it caused by corrosion? This happens when oxygen (usually from
the air) reacts with a metal. Metals with a higher reactivity (such as magnesium, aluminum,
iron, zinc, and tin) are much more prone to this kind of chemical destruction, or corrosion.
When oxygen reacts with a metal, it forms an oxide on the surface of the metal. In
some metals, like aluminum, this is a good thing. The oxide provides a protective layer that
keeps the metal from corroding further.
Iron and steel, on the other hand, have serious problems if they are not treated to
prevent corrosion. The reddish oxide layer that forms on iron or steel when it reacts with
oxygen is called rust. The rust layer continually flakes away, exposing more of the metal to
corrosion until the metal is eventually eaten through.
One common way to protect iron is to coat it with special paint that keeps oxygen
from reacting with the metal underneath the paint. Another method is galvanization: in this
process, steel is coated with zinc. The oxygen, water molecules, and carbon dioxide in the air
react with the zinc, forming a layer of zinc carbonate that protects from corrosion. Look
around your house, yard, and garage for examples of corrosion as well as galvanization and
other means of protecting metal from rust.
Technology: Fireworks & Chemistry
If you watch fireworks on the Fourth of July, you’ll see beautiful combinations of
color and sparks.
How does this amazing pyrotechnics display work? The short answer is chemistry.
The longer involves a recap of the properties of metals.
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One of the key ingredients for firecrackers, ground fireworks, and aerial fireworks
(ones which explode in the sky) is black powder, invented by the Chinese about 1000 years
ago. It’s a blend of potassium nitrate (saltpeter), charcoal, and sulfur in a 75:15:10 ratio.
Black powder is used to launch aerials and also causes the explosions necessary for special
effects like noise or colored light.
In sparklers, black powder is mixed with metal powders and other chemical
compounds in a form that will burn slowly, top to bottom. In simple firework rockets, black
powder is confined in a tube around a fuse. When lit, the powder creates a force that results in
an equal and opposite reaction, pushing the firework off the ground and then causing the
compounds inside it to explode in the air.
More complex fireworks shells are launched from a mortar, a tube with black powder
that causes a lift-off reaction when lit. The firework shell’s fuse is then lit as it goes up into
the air, and at the right time an explosion inside the shell causes its special effects charges to
burst.
The bright, colorful part of the fireworks display is caused by “excited” electrons in
the atoms of different metal and salt compounds. These compounds are in little balls
called stars, made of a similar compound to what makes a sparkler work.
Metals as Coloring Agents
Different metals burn in different colors; for example, if a copper compound is lit, its
flame will be a blue-green color. Calcium burns red-colored and potassium burns purple. In
fireworks, metals are combined to create different colors.
When the star compounds inside a firework are heated, the excited atoms give off
light energy. This light falls into two categories: incandescence and
luminescence. Incandescence is light produced from heat: in fireworks, reactive metals like
aluminum and magnesium cause a burst of very bright light when they get hot — sometimes
at temperatures over 5000 ° F!
Compounds that are less reactive don’t get as hot, resulting in dimmer
sparks. Luminescence, on the other hand, is produced from other sources and can occur even
at cold temperatures. The electrons in the compound absorb energy, making them “excited.”
The electrons can’t maintain this high level, though, so they jump back to a lower level,
releasing light energy (photons) in the process.
Barium chloride is a chemical compound that gives fireworks a luminescent green
color, and copper chloride makes a blue color. For either kind of light, it’s important to use
pure ingredients since traces of other compounds will obscure the color.
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Welding Hazards in the Workplace: Safety Tips & Precautions
Katie Martinelli March 21, 2018
Welding Safety Hazards
Welding operations present several hazards to both those undertaking the activity and
others in the vicinity. Therefore, it’s important that you are aware of the risks and hazards
welding poses, and understand what precautions you can take to protect yourself.
Some examples of the hazards associated with welding are outlined below. It’s
important to note that this is not an exhaustive list of welding hazards.
Exposure to Fumes and Gases
Undertaking welding activities will expose you to invisible gaseous fumes, including
ozone, nitrogen oxides, chromium and nickel oxides, and carbon monoxide which can easily
penetrate into your lungs. Depending on the gas or fume, the concentration, and duration of
your exposure, the resultant damage can be severe.
There is no minimum safe exposure limit for welding fume. Employers are legally
required to effectively control exposure to all types of welding fume, including that from mild
steel welding.
All organisations carrying out welding activities must ensure effective engineering
controls are in place and correctly used to suitably control welding fumes, including when
welding outside. Employers must also provide welders with adequate and suitable respiratory
protective equipment (RPE), if engineering controls are not sufficient on their own, to control
all fume exposure. More information on control methods will be discussed later in this article.
Illnesses caused by welding fumes and gases include:
Pneumonia. Regular exposure to welding fumes and gases can result in a lung infection
which could then develop into pneumonia. While antibiotics can usually stop the infection,
severe pneumonia can result in hospitalisation, serious illness and fatalities.
Occupational asthma. Chromium oxides and nickel oxides produced by stainless steel
and high nickel alloy welding can both cause asthma.
Cancer. All welding fumes are internationally considered ‘carcinogenic’.
Metal fume fever. Welding or hot work on galvanised metal and high steel weld fume
exposure can often result in ‘flu-like’ symptoms, which are usually worse at the start of the
working week. You might have heard that drinking milk before welding will help you avoid
developing metal fume fever, but this is a myth.
Throat and lung irritation, including throat dryness, tickling of the throat, coughing
and tight chests.
Fires and Explosions
Fires and explosions are two of the main hazards associated with welding and other hot
work activities. Where these are not effectively managed, severe consequences can occur,
including serious or fatal injuries and destruction of property.
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Electric Shock
During the arc welding process, live electrical circuits are used to create a pool of
molten metal. Therefore, when welding, you are at risk of experiencing an electric
shock. Electric shock is the most serious hazard posed by welding and can result in serious
injuries and fatalities, either through a direct shock or from a fall from height after a shock.
You are also at risk of experiencing a secondary electric shock should you touch part of the
welding or electrode circuit at the same time as touching the metal you are welding.
You are particularly at risk if you work in electrically hazardous conditions. These
include welding:
 In damp conditions.
 While wearing wet clothing.
 On metal flooring or structures.
 In cramped conditions where you are required to lie, kneel or crouch.
Noise Hazards
When carrying out welding activities, you are likely to be exposed to loud, prolonged
noises. A loud noise is considered to be above 85 dB(A), and welding activities such as flame
cutting and air arc gouging can produce noise levels of over 100 dB(A). This can be very
damaging to the ears and can result in hearing impairment.
Regular or immediate exposure to loud noises can cause permanent noise-induced
hearing loss.
Noise-induced hearing loss can have the following side effects:
 Ringing in the ears, known as tinnitus.
 Occasional dizziness, known as vertigo.
 Increased heart rate.
 Increased blood pressure.
Exposure to UV and IR Radiation
Looking at the intense bloom of UV light produced when welding, without
appropriate PPE or welding curtains, can result in a painful and sometimes longlasting condition called arc-eye. Many factors can affect the severity of a flash burn injury,
such as distance, duration and the angle of penetration. Long-term exposure to arc flashes
could also potentially result in cataracts and lead to a loss of vision.
Other forms of eye damage include:
 Foreign bodies entering the eye, including grit, sparks and dust.
 Particulate fumes and gases, which could lead to conjunctivitis.
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Burns
The combination of high-temperature welding arcs, UV rays and molten metal means
you are susceptible to severe burns when welding. These burns can affect the skin or eyes and
can be very serious. They can also happen very quickly.
Burns usually occur when welders think they can skip taking precautions for a few quick
welds. This is bad practice. If you follow our precautions outlined below, you should be able to
prevent burns.
Welding Safety Precautions
Ensuring high levels of safety is vital when undertaking any welding activity. Your
employer has a legal responsibility to ensure that the risks in your workplace are assessed,
controlled and monitored. They must ensure that a risk assessment is undertaken for your
workplace and work activities, either by themselves or another competent person.
The information below provides more information on some of the control measures that may be
used in your workplace. This is not an exhaustive list.
Make proper use of engineering controls and respiratory protective equipment (RPE)
As of their 2019 Safety Alert, the HSE has strengthened its enforcement expectation for
all welding fumes, including mild steel welding. Employers must ensure that suitable controls
are in place for any welding activities, no matter the activity duration.
Employers must enforce suitable engineering controls, such as Local Exhaust Ventilation
(LEV), for all indoor welding. General ventilation is not an adequate control to reduce exposure
to welding fumes. Where engineering controls alone cannot adequately control exposure,
suitable RPE must be provided. RPE must be provided to workers welding outdoors to protect
them from exposure.
The HSE will no longer accept any welding undertaken without suitable exposure
control measures in place, regardless of duration.
All welders must be appropriately instructed and trained on any control measures, and
must be competent in their duties. As an employee, you must comply with any control methods
your employer enforces and to work in line with the training and instruction provided to you.
Further information on engineering controls, including LEV systems, can be found in our
training course: Welding Health and Safety Training Course
Always Wear Appropriate PPE
Your employer or manager has a duty to provide you with appropriate Personal
Protective Equipment (PPE). The PPE you receive will likely include:
Respiratory protective equipment (RPE). Where engineering controls alone are not
sufficient to suitably control exposure to welding fumes, RPE must be provided. Anyone
welding outdoors must wear RPE when welding. Your respirator must be suitable for the
work being undertaken, for your specific requirements, and must be thoroughly examined by a
trained individual at suitable intervals.
Welding helmets with side-shields. Welding helmets protect you from UV radiation,
particles, debris, hot slag and chemical burns. It’s important that you wear the right lens shade
for the work you are carrying out. Follow the manufacturer’s guidelines and gradually adjust
the lens filter until you have good visibility that does not irritate your eyes. You should also use
a fire-resistant hood under your helmet to protect the back of your head. You must always wear
your helmet when welding and when in the vicinity of another welder. While the intensity of
the radiation produced decreases the further you are from a welding arc, those less than 10
metres away are still susceptible to arc-eye. Therefore, it’s important that you remain behind
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welding curtains or wear the correct PPE, even if you aren’t the worker carrying out the
welding operation.

Fire resistant clothing. Fire resistant clothing protects you from heat, fire and radiation
created in the welding process and shields you from burns. It should have no cuffs, and
pockets must be covered by flaps or taped closed. You should not use synthetic clothing.
Instead, opt for leather and flame-resistant treated cotton. You must not roll up your
sleeves or trousers as this will leave you susceptible to molten metal or sparks getting
caught in the folds, which could potentially lead to severe burns. You should also never
tuck your trousers into your work boots.

Hearing protection. Hearing protection protects you from noise hazards. It’s important
you wear ear protection that is appropriate for the noise created in your workplace, and use
fire resistant ear muffs if there is a risk of sparks or splatter entering the ear.

Boots and gloves. Insulated, flame resistant gloves and rubber-soled, steel toe-capped
safety shoes shield you from electric shocks, heat, fire, burns and falling objects.
Follow any training, communication and housekeeping information your employer has
provided
Employers have a legal duty to ensure their workers are effectively trained in their
duties. They must also ensure that employees and, where necessary, those in the vicinity are
effectively briefed.
Any relevant information about the equipment you use, or your work activities, must be
communicated to you and training must be provided where necessary. This includes
information on the risk assessments and control measures used in your workplace.
You have a legal responsibility to work in a way that ensures your health and safety and the
health and safety of those around you. It’s essential that you:
 Work in line with the training and instruction provided to you by your employer.
 Cooperate with your employer in any matters relating to health and safety.
 Properly use any control measures enforced as a result of the workplace risk assessment.

Carry out the required pre-welding checks
You should carry out visual checks of your welding set before every use to ensure that
the welding and current return cables are undamaged, all connectors are clean, undamaged and
correctly rated for the required current, and that the conductor is thick enough to carry the
current safely.
Information on how to carry out these checks should be provided to you as part of the
training and information you receive from your employer.
You should never use welding cables, plugs, clamps or torch/electrode holders with damaged
insulation.
Cooperate with any health surveillance requirements
Generally speaking, any employee exposed to welding fumes should have regular health
surveillance. Health surveillance is essential for ensuring that ill health effects are detected early,
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and can help employers to identify areas where their control measures may be insufficient. You
should cooperate with any health surveillance requirements your employer enforces.
Parts and functions of SMAW machine:
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Techniques on how to start a weld
Author: NJR Steel Article Views:48021 Categories: Manufacturing, DIY
This article is intended to teach you how to use a flux cored arc welder. This machine
is one of the most basic welders available on the market today and is known for being both
user-friendly and cost-efficient. Although there are several limitations as to what you can get
away with on this machine, it is a great welder for beginners and is perfect for doing nonstructural, ornamental welding.
An example of a flux cored arc welder
Step 1: Safety
The first and most important thing to consider while using any sort of welder is safety.
Not only is the electricity required for arc welding extremely hot, but it also generates
dangerous UV light that can easily damage your eyes if you look directly at it. This is why
you should always use the proper Personal Protection Equipment (PPE) while working on
your welding project. This includes, but is not limited to: safety glasses, leather welding
jacket, welding gloves, and of course, the welding mask (also known as a welding hood). It
also really helps if you have long pants and close-toed shoes. Flux Cored Arc Welding
(FCAW) is known to generate lots of sparks that can easily burn any unprotected areas of
your body, so cover up! These sparks can also easily start a fire, so any flammable materials
should be kept at a reasonable distance from the welding area.
That being said, welding can be a fun and exciting way to make things out of metal
and after a bit of practice, there is endless potential to make some really cool stuff. So, lets
get started.
Step 2: Gather necessary equipment
Before you start welding, you will need to make sure you have all the tools required
for the project at hand. The following list should contain everything you will need over the
course of your welding project:
 Safety glasses
 Welding mask
 Gloves
 Leather jacket
 Ear protection
 Pliers
 Chipping hammer
 Wire brush
 Grinder with cutting/grinding/wire wheels
 Clamps
 Magnets
 Tape measure / metal ruler
 Fume extractor
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and of course, the welder!
Step 3: Clean your metal
Although FCAW is known for being a process that can get away with welding dirty
metal, it is still important to clean the area of the metal you plan on welding. This is generally
done with some sort of wire brush, grinder, or even better, a grinder with a wire wheel.
Removing contaminates such as rust or paint will drastically increase the quality of your
welds, so taking the time to clean up your project before you start welding is always a good
idea.
Prior to taking the grinder to your work-piece, you should always take steps to make
sure the metal you plan on grinding is secure. This is generally done with clamps, but
preferably not spring clamps as they don’t always exert the necessary force required to keep
the metal in place while grinding on it. Weldors often prefer either a table vice or a C-clamp,
as these tools allow the weldor to control the amount of pressure being applied to the workpiece.
Once the metal is secure, you are free to grind away until you have removed the
majority of the substance getting in the way of the bare metal. While grinding, be sure to
direct any sparks in a safe direction (i.e. not towards a person or a flammable object).

A weldor cleaning a sheet before welding
Step 4: Cut your metal
In addition to welding metal that has been sufficiently cleaned, you should also make
sure your metal has been cut to the appropriate length. Correctly cutting your metal can be
equally if not more difficult than the actual welding, depending on what you are working with.
An accurate cut starts with an accurate scribe, or mark, on the work-piece. This is generally
done with a soap stone or felt-tipped pen and a ruler with a straight edge. Once you are
satisfied with your markings, you can start cutting your work-piece When cutting extended
lengths of sheet metal, it is a good idea to use some sort of guide to ensure a straight cut, like
an angle or a long piece of square bar stock. For each cut, you should clamp the work-piece
down so that it doesn’t go anywhere once you begin cutting.
Cutting a sheet of metal
Step 5: Set up your work-piece
Once you have cleaned your metal and cut it to the appropriate dimensions, it is time
to get your work-piece set up so that you can easily tack-weld it together without having to
fight with it too much. For mass production work, this is where you would typically devise
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some sort of jig that would allow you to easily set your pieces into place without having to
think about it.
Making sure that the pieces you intend to weld are secured in the exact position you
plan on welding them is extremely important. Welding loose materials can lead to countless
mistakes and can add unwanted extra work to your project, so make sure to double and triple
check your work-piece before you lay down your first tack weld. After you’ve lined
everything up accurately, it is time to start welding!
Step 6: Turn on the welder and adjust the settings
Of course, adjusting the welder to the appropriate settings is another essential part of
your project. If your sheet metal is a fairly thin gauge, weld on a lower setting with a lower
wire speed. As the metal you are welding increases in thickness, you will want to increase the
voltage and wire speed as you see fit. It is always good to do a couple test welds on some
scrap metal to make sure your settings are right where they need to be before you actually
start on your project.
If you are unsure about what settings you should use for your own project, refer to
your user manual.
Step 7: Tack-weld the work-piece
After you’ve got everything lined up correctly and set your welder to the appropriate
settings, tack-weld the corners of your work-piece together. When tack welding, it is
important to make sure that you are actually fusing both sides of the metal together. When
you pull the trigger on the torch, pay attention to where you are depositing the weld metal and
that you are hitting the work-piece exactly where one piece comes in contact with another.
Welding one side more than the other will lead to a lack of fusion which can result in the two
pieces of metal not joining together properly. Remember to clean up the area you just welded
with the wire brush to remove any slag generated from the tack weld.
Ideally, once you have tacked each corner together, your work-piece will have taken
shape and you will be able to see if the sides are aligned and welded into the right position. If
not, now is the time to fix your mistakes, as they will be much harder to correct after you
finish welding!
A small box with its corners tack welded together
Step 8: Fill in the remaining areas with ‘bead’ welds
Assuming that you tacked everything together correctly, you can now go back and fill
in the remaining seams with bead welds. This is where you will really get to hone in your
welding skills, so pay close attention to how your torch angle, travel speed, and electrical
stickout affect the appearance of your welds.
The most important thing to consider while performing these welds is maintaining
consistency in the above categories. In other words, once you’ve figured out the proper torch
angle, don’t change it mid-weld. Your travel speed should be fairly fast, and you don’t want
to speed up or slow down mid weld, but maintain a constant pace. Lastly, your electrical
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stickout should never be more than 1/2” or less than 1/4”, so keeping it at around 3/8” will be
your best bet.
Mastering the consistency of your welding technique is the key to being able to weld
proficiently, and it’s going to take some practice before your welds come out looking perfect.
Keep this in mind if they don’t look great on your first try, just be patient remind yourself
that practice makes perfect.
Bead welding the tacked welded sheets together
Step 9: Clean up your piece
After you’ve welded everything together, there is going to be a bunch of spatter and
slag left over from the flux. Now is the time to use the chipping hammer and wire brush to
remove as much of this as possible before you start grinding.
Once you’ve removed as much as you can by hand, grab your pair of locking pliers
and clamp it to one of the outside edges of the work-piece. Carefully use the bench grinder to
grind down your welds until you’ve basically removed the outer layers of your weld and the
corners are flush with the sides. While grinding, make sure you keep the work-piece safely
rested on the guard. You will probably have to re-clamp your locking pliers once or twice in
order to effectively grind each corner. If you welded the edges correctly, each corner should
look like a seamless transition on each side and should be free of any holes or cracks. If not,
you may need to go back and re-weld the areas with defects and repeat the cleaning/grinding
process until you reach the desired results.
At this point you are basically done with your weld!
Step 10: Clean up the area
Clean up the area you were working at and put all the tools back where you found
them. This will make your next welding session all the more efficient.
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Self-Activity Test/ Assessment:
Direction: Write your answer on a coupon bond A4 size paper and submit via private
message to your course facilitator. Use only New Times Roman font style and 11 or 12 font
size including the CapSU ISO format.
Take Note: No answers should be the same with your classmates or copy/paste method, this
will not be recorded or no grade at all. Mind your own answer.
1.
Discuss and Explain Metallurgy according to your own understanding.
2.
Explain and Discuss according to your own understanding. Characteristics/Properties and
uses of the different metals
3.
What is Shielded Metal Arc Welding( SMAW)? Explain and Discuss according to your
own understanding.
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References
Metallurgy - Definition, Principles & Examples - Byju's https://byjus.com
chemistry › processes-of-metallurgy
The
Difference
Between
Ferrous
Metalhttps://www.metalsupermarkets.com › Blog Sep 23, 2015.
and
Non-Ferrous
Metallurgy September 2018 DOI:10.1007/978-3-319-51726-1_2715-1In book:
Encyclopedia of Global Archaeology, Smith, C. (Ed.)Publisher: Springer
Properties of Metals Science Lesson | HST Learning Center https://learningcenter.homesciencetools.com metals-101
PROPERTIES AND USES OF METAL - Design Technology Infohttp://www.designtechnology.info › alphaindexPDF
Welding Hazards in the
https://www.highspeedtraining.co.uk
Workplace:
Safety
Tips
&
Precautions
TVL – IA (Shielded Metal Arc Welding NC II)Learning Activity Sheet (LAS) No. 1
First Edition, 2021
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