1. Oxy Acetylene Welding and Cutting
Equipment and Setup

2. Required Oxyacetylene Welding Equipment
Oxygen regulator
Acetylene regulator
Oxygen/ Acetylene welding hose
Hose couplings
Single-purpose cutting torch or welding torch
Cylinders and cart for portability
Flash arrestor and check valves (protective equipment)
Flint lighter to ignite torch

3. Approved Protective Equipment
Installed in OAW system to prevent:
Backflow of oxygen into fuel-gas supply system
Passage of flashback into fuel-gas supply system
Excessive back pressure of oxygen in fuel-gas supply system

4. Equipment Wide assortment of tips
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5. Equipment setup for welding
Portable tank outfits are mounted on a truck
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6. Pressure Regulators
Reduce high cylinder pressure to relatively low pressure of 0 to 45 p.s.i. used for welding
Maintain pressure without variation during welding
Flame remains steady and uniform
Two pressure gauges mounted on body of regulator
One shows pressure in cylinder, other pressure of gas being supplied to torch

7. Pressure Regulators Pressure of cylinder
Pressure of gas being supplied to the torch
Pressure of cylinder
Hand screw which adjusts working pressure
Union for attachment to cylinders
Outlet connection for hose leading to torch
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8. Regulator Construction
Internal mechanism of oxygen regulator
Oxygen Enters regulator at left at 2,200 p.s.I. and must leave regulator at desired pressure for welding – 10 p.s.i.
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9. Regulator Construction
Force that opens valve provided by tension of spring
Force that closes valve provided by high gas pressure from tank
When two forces balanced, constant flow of oxygen to torch results

10. Two Types of Oxyacetylene Welding Torches
Injector
Acetylene carried through torch and tip at low pressure by suction force
Higher oxygen pressure passing through small orifice of injector nozzle
Mixing head and injector integral part of tip
Equal (balanced-pressure)
Both gases delivered at equal pressures
Mixing head separate replaceable unit in body of torch

11. Injector Torch The acetylene is carried Through the torch and tip at
Linde Division, Union Carbide Corp.
The acetylene is carried
Through the torch and tip at
low pressure by the suction
force of the higher oxygen
pressure passing through the
small orifice of the injector
nozzle.
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12. Injector Type Mixer
The oxygen passing through the Venturi (1), pulls the fuel gas available in chamber (2). The gases are mixed, starting at point (3).
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13. Equal-pressure (balanced-­pressure) torch
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14. Balanced-Pressure Type Mixer
The two gases are fed in at points (1) fuel gas and (2) oxygen
The gases are mixed, beginning at point (3), throughout the mixing chamber.
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15. Torch Tips Size measured by diameter of end opening
Marked on side of tip
Most common system: numbers from
Larger the number, larger hole in tip and greater volume of heat provided
Tips for injector torches provided with individual mixers so mixer and tip one unit
Most made of pure drawn copper

16. Oxygen and Acetylene Hose
Especially manufactured for purpose
Siamesed (two built in one)
Colors of Hose
Green for oxygen
Red for acetylene
Black for inert gas and air
Thermadyne Industries, Inc.
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17. Thermadyne Industries, Inc.
Lighters
Use friction spark lighter to light welding torch
Safety note: Never use matches
Puts welder's hand too close to torch tip where it may be burned when gases ignite
Gas lighters may explode in your hand or pocket.
Thermadyne Industries, Inc.
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18. Filler Rod Most gas welding done with filler rod
Provides additional metal to form larger weld bead
Many diameters, available in bundles of 50 or 100 pounds and boxes up to 300 pounds net weight
36 inches long
Steel rods copper coated to prevent rusting
Some aluminum rods flux coated
Both Braze and aluminum 28 inches long