Oxy Acetylene Welding and Cutting
Equipment and Setup
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
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
Equipment
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Wide assortment
of tipsThermadyne Industries, Inc.
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Equipment setupfor welding
Portable tank outfits are
mounted on a truck
Thermadyne Industries, Inc.
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
Pressure Regulators
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Union for attachment to cylinders
Outlet connection for hose leading to torch
Pressure of cylinder
Pressure of gas being suppliedto the torch
Hand screw which adjusts working pressure
Thermadyne Industries, Inc.
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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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
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
Injector Torch
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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.
Linde Division, Union Carbide Corp.
Injector Type Mixer
The oxygen passing through theVenturi (1), pulls the fuel gasavailable in chamber (2). The
gasesare mixed, starting at point (3).
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Equal-pressure (balanced- pressure) torch
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Balanced-Pressure Type Mixer
The gases are mixed, beginning at point (3), throughout
the mixing chamber.
The two gases are fed in at points (1) fuel gas and (2) oxygen
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Torch Tips
• Size measured by diameter of end opening – Marked on side of tip
• Most common system: numbers from 000-15– 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
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
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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.
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Thermadyne Industries, Inc.
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