Notesale: Turn your study into money

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Josh Glaister

QPE02 028N
1
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You must use safe working practices
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Make sure all exits are not blocked and you can easily exit in case of any
emergency
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Once you have
checked all of these it is vital you check your last line of defence
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When welding
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If you wish you can wear additional PPE such as repertory
systems etc
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You need to think about your
colleagues or anyone else that may be around you
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If any one wishes to enter, it is a good idea you make them wear
a welding screen when in the bay otherwise you stop and/or go outside of the area
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2
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There are many hazards associated with TIG welding such the ark
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Enough heat to
make molten metal
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If you never worn
PPE a lot of things could happen to you
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This occurs by
looking into an ark
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Thirdly, electrical
shocks, these can occur by poor earthing, bad wire insulation or electrocuting yourself with
the tungsten by simply pressing the button
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But, it could be a lot worse
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Fourthly, trips, tripping are very common when it comes to welding
and that is because there are so many leads trailing to and from the set
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There are other ones but they are not used
at all times such as the purge hoses
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Describe the PPE to be worn for welding activities (such as correctly fitting overalls;
leather aprons; welding gloves; safety boots; head/eye shield with correct shade of filter)
First of all, when welding your PPE is your last line of defence exactly like it is in all cases
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Not with maximum

Josh Glaister
PPE and extreme safety precautions
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The welding screen dims the welding ark so you can see it clearly and
easily
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The welding screen doesn’t just do that it prevents the UV
rays from burning your face and eyes
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The fire retardant overalls will stop you from getting set on fire
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If you try to lift a job at
it is to hot or it slips out of your hands and lands on your feet it will not hurt what so ever
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You
can also use things like fire retardant hoods
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You can also use RPE systems to stop inhaling harsh dusts and
fumes
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Describe the correct handling and storage of gas cylinders (such as manual handling and
use of cylinder trolley, leak detection procedures relevant BCGA codes of practice cylinder
identification, gas pressures, cylinder and equipment safety features)
Handling and storing gas cylinders is very important that it is done properly by following the
manual handling operation regulation 1992; if it’s not handled properly it could cause a
serious injury or even death
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For a first example I will talk about the cylinder trolley
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Once you have placed the cylinder on
the trolley by simple rotating it to make in move you must chain it on to ensure it will not
fall
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Once there you have to undo the chain and rotate the bottle to the area where
it will be stored
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Never leave it free standing
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If you have found a leak check to see the valve
is fully tightened
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When you return to the
area make sure it is well ventilated and do not ignite any naked flames
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Explain how to use and extract information for engineering drawings and related
specifications (to include symbols and conversations to appropriate BS or ISO standards) in
relation to work undertaken
When using and extracting information from an engineer drawing you must read thoroughly
as they can be extremely complex and an easy drawing can be made hard by missing one
thing out
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If a reference line is pointing at a joint it will
they you what type of joint it is, what type of weld, where to weld and how to weld it
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If you don’t you could actually build whatever it is the wrong way
round or just find it extremely difficult to make
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It can either be BS (British Standard) or ISO
(International organization for standardization)
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But other counrties make there own just like BS
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Describe manual TIG welding process (such as basic principles of fusion welding; the major
parts of the welding equipment and their function)
Fusion welding is where two pieces of metal are heated so much they are melted together
and can be done with filler wire to make the weld stronger
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Heat, shielding, filler material and distance
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First of
all, the tungsten, this is used to pint the electricity (heat) the way you want it to go
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Many people also use it for balance during some welds
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Fourthly, the gas passage, this lets the gas out
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Without this the set could
not ark up and would be useless
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Describe the types, selection and application of filler wires and welding electrodes
When it comes to TIG welding there are many types of filler wire and can be tricky when it
comes to choosing the right one
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308L wire is usually used on austenitic steels like 301, 302, 304
and 305
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8
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There are other types
of shield gases such as oxygen and carbon dioxide but they are used for other types of
welding as they are both active gases
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When it comes to TIG welding, The gas is called “inert” gases not “active” gases
hence the name “tungsten inert gas” this is inert gases as the gas does not react with the
molten weld
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Describe the gas pressures and flow rates (in relationship to the type of material being
welded)
As a rule of thumb, it is necessary to set the gas pressure at around 10-12 PSI
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Also this PSI can also keep the ceramics cool and help prevent it
from cracking
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This will release more gas meaning
you can weld faster and the weld will still be clean from any impurities
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10
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One type of weld I
will be doing is the tee joint
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This is one probably the easiest
weld as or is continuous and only has one tricky party which is the beginning where you have
to free hand weld for a little bit
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The second weld I will be doing is the lap joint
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This joint is also
similar to the tee joint as it is continuous once you have passed the start
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Finally I will be doing
an outside corner joint; this consists of two plates corner to corner making a 90◦ gap to fill
with weld
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Finally butt welds, the
edges of the two plates are aligned on the same plane making it all completely flat
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Describe the correct terminology for the appropriate welding positions
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Such as PA, PB, PC, PF, PG
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once again
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The flat position is down hand
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Secondly, horizontal
vertical, this is just what you would do with a standard fillet joint sitting on a table
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Fourthly, the vertical
upwards position, this is where the plate sits vertical and you will start with the torch at the
bottom of the plate and weld upwards to the top fighting gravity
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But, when you come to weld you run
downwards towards the floor and working with gravity
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Explain how to prepare the materials in readiness for the welding activity (such as
ensuring that the material is free from excessive surface contamination – such as rust,
scale, paint, oil/grease, and moisture; ensuring the edges to be welded are correctly
prepared – such as made flat, square or bevelled)
When preparing plate to be welding it has to be top standard to avoid any defects such as
porosity in the welds
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you need to use something such as a grinder, sand paper of a file
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You must take this off your material because scale is a
finish
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That’s not all you should clean off
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Next, bevel, square your edges off
simply with a grinder to how ever you want it
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13
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I will start with a tee fillet
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This is so I can get a
G clamp of the other side of the plate
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This will hold it down and stop it from
moving about
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Lap joints, when setting up at lap joint you can use G clamps as well
to apply pressure to the plates to make them tightly pressed
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With lap joints you can use a certain jig called a “dog” this uses a

Josh Glaister
wedge to depend on how much pressure you want
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Corner joints, I like to use a vee block to
align the two plates to where they should be and use a piece of wire to help set the gap
between them
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For example, if I was going to tack weld a 1 ½ “schedule 40 pipe
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4mm gap wire in and then align the pipes in a pair of vee block and get one
singular bridge tack about 2-3mm long then I would place one directly opposite to the first
one and then again 90 degrees and finally one last one to make four tacks which will keep
the pipe in place and aligned
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If I was about to weld a tee fillet I would make sure the plates are 90 degrees
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If I was welding a butt on a
pipe I would tack weld the pipe in four positions while sitting in vee blocks, this will make the
pipe perfectly aligned
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That’s not it; I will examine the tungsten if I was TIG welding for anything on
the end of it
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Electrical
connections, this is vital all the connections are good otherwise you will not be able to weld
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Next I could look up
and down the wire searching for any slits or other lose/hazards
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16
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For example, a fillet joint, when welding this you cannot just load the wire in however you
want
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This is
easier because you are working with gravity and not against it
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You can also use a technique called “walk the cup” this is basically jamming the ceramics
between the horizontal and vertical plate then releasing the weight off one plate and laying
the pressure on the other so they can move the ceramic
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This is good because it keeps your balance rather than free hand
and you can make your weld neater easier
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This helps you massively to get full
penetration and strengthen your weld
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When it comes to blending in stop

Josh Glaister
starts you can use one technique which is basically stopping your weld then start welding
about 5-8mm back on the weld and carry on
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17
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There are many ways to control distortion with every job
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These are
fairly easy to control as all you would have to do is deposition the pipe by sitting the pipe on
vee blocks with the stubs facing up
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Once this is done you have to weld them in sequence
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You do this all the way to the centre and then leave the pipe to cool to room temperature
and then take the G clamps off the bench/table
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Such as a vice, dog or G clamps
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They all either squeeze the plates together of squeeze the
plates to a bench or table
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Describe the problems that can occur with the welding activities (such as causes of
distortion and methods of control; effects of welding on materials and sources of defects),
and how these can be overcome
When welding, lots of problems can occur
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It can cause it to bend or even burn right through causing a hole
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First you can reduce the amps on the welding set
which could possibly make it harder and slower
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If you do this you must wait until
the material has cooled right down to room temperature because it will still pull and bend if
there hot
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This is better as it will take
longer to heat up and if you are fast enough you could avoid distortion and it will be harder
to burn through
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These are often caused because of dirt/grease/scale getting into the
weld
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All of these are fairly easy to avoid
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When you thing the welding set is causing the problems you
should get it cleaned out and checked by someone or you can simply use a different
machine if it still occurs
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g
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19
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When I close down welding equipment I like to
do it in a certain order
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This is because people are
most likely to forget about them
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Then turn the machine off

Josh Glaister
using the switch which is usually located either at the back or front of the machine
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Next wrap the wires up so no one can trip over them and put
them in an appropriate place such as on top of the machine or a shelf
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20
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This will help pass
the examinations as any grease or dirt on the weld cannot be mistaken as a crack or a hole
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You can also use pickling paste to take the discoloration out of the metal
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Explain how to prepare the welds for examination (such as removing surface irregularities;
cleaning the weld, polishing and making saw cuts on welds that need to be fracture tested)
When preparing the welds for examination it is vital that they are clean
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You can clean the weld by firstly using a wire brush on the material after
it has been welded but this will not have cleaned the weld to a high standard so I like to use
pickling paste to remove anything else not need on top of the weld
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How to prepare for fracture tests? If I was going to do a nick break weld test I
would first use a cutting disk or a hack saw on the weld surface right along the centre and
engrave about 2-3mm deep depending on how thick the weld is
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Now the materiel is bent
to break the weld in half and can now be visually inspected
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So this is why a lot of people tend
to use sand paper or files to be more accurate and reduce the risk of ruining the weld
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Explain how to check the welded joints for uniformity, alignment, positioning, weld size
and profile
How would I check a tee joint is exactly 90 degrees? This is the easiest one to check as you
can use an engineer’s square and push it into the corner
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This is because all engineers’ squares
should be exactly 90 degrees
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For the table trick all you
have to do it sit the late on a flat table and look to see if there is any gaps between the plate
and table and if there is the plate it not straight and has deformed
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If there are no gaps the plate is straight and hasn’t
deformed
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If there are a gap you this means either the pipe is bent or stepped (not aligned) this is not
the only way to check
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24
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26
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If there are any gaps this will show any steps of bends
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For example, looking
for cracks, the process for this is very simple
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How do I visually inspect for porosity? One easy way of doing this (NDT) nondestructive test is simply looking at it with adequate lighting and a 30 degree angle of the
head or material
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You can also visually inspect for porosity by using dye
penetrant
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First of all you should clean the plate or
pipe from greases, liquid or anything else that shouldn’t be there, next you should apply the
first spray, the excess liquid is wiped off, now you can add the second dry or liquid developer
spray
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Describe the various procedures for carrying out destructive tests on the welds (such as
macroscopic examination, bend tests and nick break tests)
I will start off with the destructive test I use the most, the nick break test
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You start off with either an abrasive disk, hack saw
or an oxyacetylene torch
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The
next destructive test is the back bend test
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This can’t be too small as if
won’t fit on the rollers
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Now all you have to do is push the leaver down and measure
how much force you are applying
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If
you want to test your cap weld you should face it towards the floor
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Explain how to examine the welds after the tests and how to check for defects such as the
degree of penetration and fusion, inclusion, porosity cracks, undercut, and overlap,
uneven and irregular ripple formation
The best way to examine welds is to have decent lighting in the area (no reflections and not
to dark), the inspector should be no further than 24 inches away from the material and
finally be at a rough angle of 30 degrees so you can see any cracks easier
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This process in easy and is very accurate
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Finally you will see a florescent
indication if you have any porosity or other defects in the welds
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This is a
pretty simple process and doesn’t take too long
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You should cut to about 2-3mm deep and go right
through the centre of the weld and cover the full length, now all you have to do is give the
material a few blows with a hammer until the weld completely splits or use a machine to do
it for you
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“If in doubt, ask” you will see
this quote written on top of engineer drawings and even about your workshop
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But sometimes there will be no need
to ask, for example if I knew what to do and exactly how to do it
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But if you have a feeling you are doing something wrong or
something has been done wrong don’t be afraid to ask
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This is not just for you but this is for others
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Or you could even forget that you have left them and you could hurt
yourself
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For example if
you didn’t completely isolate a machine and the machine caught fire the whole building
could catch light or even explode and leave you or even everybody else without a job,
perhaps with deaths or injuries

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