Oxy acetylene can’t cut through rust, so when the oxygen hits the rust layer on the underside of the steel it will bounce back giving you a poor quality cut. Using the correct nozzle size will also make a big difference to the quality of the cut. Any more suggestions to keep in mind? Here's a document about oxyacetylene awareness that keeps you in the loop? #safety #oxyacetylene #awareness #oxygen #elearning

1. Oxy-acetylene
(Propane Gas)
Awareness
Some lesser discussed facts - for
it impacts HOT WORK

2. Something to ponder over…
If you believe that you can skip safety guidelines for oxy-acetylene
equipment, allow us to mention that –
If you’re wondering how, let’s talk about gases and systematically
understand this!
In such cases, it would be same as handling live explosives that are
ready to go off….
Shocking? Isn’t it?
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3. Oxygen is…?
Approximately 21% in the normal air
It is produced industrially by distilling air below it’s freezing point
Pure oxygen does not burn or explode
But it is an “accelerant” - it causes everything that meets, to burn
hotter and faster
With a vapor density of 1.000, Oxygen is heavier than air (1.105)
This means if a oxygen bottle is leaking, the gas will settle in low
areas before diffusing back into the atmosphere.
3
Even 30% oxygen in the
atmosphere will cause
things to burn or
explode 8 times faster
“
“

4. Never use Oxygen for..
In pneumatic tools
4
the oil and the gas pressure friction can cause a fire or explosion
In oil pre-heating burners-
these burners are set to burn with 21% oxygen to air ratio
To start internal combustion engines
gasoline is flammable enough with 21% oxygen available
To blow out pipelines
Leftover flammable or combustible vapours may still be
present to cause an explosion

5. And what about acetylene?
Acetylene is a compound of Hydrogen and Carbon (C2H2) a member of
the hydrocarbon gases
Explosive range is 3.0 to 93%
5
Produced when calcium carbide is mixed with water
It is an unstable gas, will violently decompose when in a pure state
above 15 psi
Auto-ignition temperature is 763o - 824o F, this means if acetylene
reaches 30 psi in a free state, it can explode by itself without a spark or
flame being present
Needs only 10% of oxygen to ignite

6. Does it explode in a bottle? If no, why?
Acetylene burns in air readily, and is most safely hand- led in
cylinders filled with crushed firebrick wet with acetone.
Acetylene happens to dissolve readily into acetone, the dissolved
gas is no longer in contact with gaseous O2 (which does not tend to
dissolve in acetone) and is not as prone to decomposition by O2.
The firebrick helps by minimizing the free volume of the cylinder,
cooling and controlling any thermal decomposition before it gets
out of control (each decomposition of acetylene gives off heat).
6

7. Constructing Oxygen and Acetylene bottles
Usually constructed of steel
Hollow in construction
An electric arc can cause an oxygen bottle to explode
The orifice at the top of the bottle is the diameter of
the lead in a pencil (if the bottle top gets damaged,
bottle becomes projectile causing injury or property
damage
Never allow a tank to go empty
Keep free from oil and grease
7
Usually are steel construction
Porous filler(8-10%), Acetone(42%)
Acetylene gas(36%),
Never allow a tank to go empty (Oxygen may back
pressure into the bottle)
Must be stored upright (This prevents the acetone
and acetylene from separating)
Should not be stored below freezing (Acetone may
come out instead of acetylene).
Some facts about Oxygen bottles Some facts about Acetylene bottles

8. Prioritizing one by one
8
Gas regulators Backfires and
flashbacks
Valves Hoses

9. Gas regulators
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Warning - Always keep the
regulator free of oil, grease and
other flammable substances
Never use oil or grease on the
regulator, cylinder or manifold
connection
DO NOT change the inlet connection
on a regulator in an attempt to use the
regulator for a different gas service
2
1 3

10. Backfires and flashbacks
Backfires occur when the torch flame burns back into the torch tip
and is extinguished with a loud pop.
They occur either because the torch tip touched the work or because
of insufficient gas pressure.
They are generally harmless. However, flashbacks are more serious
when the flame front does not extinguish, but burns back sometimes
beyond the mixing chamber, through the hoses, and even into
regulator and supply.
10

11. The purpose of an internal check valve is to reduce the
possibility of reverse flow gas.
11
1
3
2 It is not intended to act as a fire stop!
Ensure that the internal check valves are working properly
by testing at least every six months, more often if the
hoses are frequently removed from the torch.
Valves

12. Hoses
Keep welding hoses clear of any failing metal, slag or sparks.
Never allow hoses to become coated with oil, grease or dirt. Coatings
could conceal damaged areas.
Examine the hoses before attaching to welding torch handle or
regulators.
If cuts, burns, worn areas or damaged fittings are found, replace the
hose.
Completely replace welding hose if it contains multiple splices or
when cracks or severe wear is noticed.
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13. Training escalates familiarity and expertise
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Information to understand
the specific hazards
results in an assured
workforce and a safer
workplace.
Ensures organisation
complies with obligations
to train all staff exposed
to risk.
The more an employee’s
greater is his amorale
more contribution to
organizational success
Well trained employees
show both quantity and
quality performance.
Ongoing employee
training enhances
experience which makes
them viable for senior
roles
1 2 3 4 5

14. Your E-learning Story Starts Here
Press the button. Make the call. Transform your trainings.
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