Transcript Document

Oxyacetylene is a combination of the words oxygen and acetylene. It refers to
the equipment and processes where 2 gases are used together. (In our set up
we use MAPP gas and oxygen.)
MAPP = methylacetylene-propadiene
A portable oxyacetylene rig includes a cart, cylinders, valves, regulators,
gauges, hoses, & torch assemblies.
Torch is an assembly that mixes gases and discharges them to support a
controllable flame.
A gas cylinder is a long round tank with extremely thick walls built to hold
gases under pressure.
Valve is a device that allows gas to flow from cylinder.
Regulator is device that keeps the pressure of flowing gas at a constant rate.
Gauge is mounted on a regulator to measure and indicate pressure in the
hose, tank, or manifold.
Check valves prevent a flame from reaching gas in the cylinder.
Hoses are flexible lines that carry gases.
Red = fuel gas
Green = oxygen
Always green in color
Have right-handed threads
Made of high carbon steel
Extruded (made out of one piece of metal)
Full tank has a pressure of 3360 psi
Oxygen in a cylinder is 97% pure
Double-seated valve made of brass so it’s soft and self-seals
Oxygen speeds up the burning process
Inspected with a hydrostatic (water pressure) inspection every 10
years and stamped on tank when passed
Open all the way and SLOWLY
Threaded ring on top oxygen cylinder holds cap on (never attempt to
move without cap on!)
Tank owners’ names are stamped on top of cylinder by the rings
Never use oil or grease on or around oxygen equipment
Never use oxygen to blow dirt off clothing or equipment
Always red in color
Full tank is 250 psi
Left-handed threads are identified by groove on hex
Unstabilized (aceytlene in its natural state) is dangerous
above 15 psi
Porous material absorbs aceytlene in the cylinder
Acetone stabilizes acetylene
Cylinder valves made of brass because it doesn’t spark
Safety device is fusible plug (temperature above 212
degrees F)
Visual inspection every time it’s filled
Never use laying on its side
Only open ¼ turn
Reduce cylinder pressure to adjustable, safe constant
line pressure
A metallic filter in the stem of the gauge to prevent
damage to the hose.
Turning the regulators t-screw to the right increases
the working pressure
Backing out t-screw all the way will stop working
pressure
Regulator gauge closest to the cylinder indicates tank
pressure
Oxygen regulator provides a 3360 psi bursting disk
Work area must be cleared of all flammable materials
First step before using a torch outfit is to crack each
cylinder valve one at a time to clear away any dirt or
dust before connecting the regulators and lines
Light the torch with a striker
Check valves are used to prevent back flow
Flash arrestors are used to prevent both back flow and
back flash
Back fire is a loud pop
Back flash is burning in the handle
Minimum distance between cutting area and torch
outfit should be at least 10 feet
When bleed the hoses, bleed them on at a time
When shutting down a torch outfit, bleed the hoses
before backing out the regulator t-screws
Size of a tip is determined by the hole diameter of it
(hole is 1/3 of plate thickness)
The large heating tip is called a rosebud
When using a tip cleaner to clean a torch tip, always
allow a small amount of gas to flow
Always cap cylinder before removing it from the cart
Safety device on the hose is a check valve
Welding tip size corresponds to flame size
Tip cleaners are rods with rough edges designed to
remove soot, dirt, or metal residue from the hole in the
tip
1)Close main valves (Acetylene first;
Oxygen second)
2)Bleed hoses one at a time
3)Back out t-screws
4)Close handle valves
5)Remove tip and replace the nut
6)Coil hoses
Acetylene
Oxygen
Cutting
5-8 psi
30-40 psi
Welding
5-8 psi
15-20 psi
Heating
8-10 psi
50 psi
Carburizing Flame: coolest flame; 5,000 degrees F; used to weld lead and case
hardening; hot inner core with a white-hot acetylene feather and blue outer cone
Neutral Flame: 5900 degrees F; light blue inner core and darker blue to colorless
outer cone; most commonly used flame
Oxidizing Flame: hottest flame; 6300 degrees F; inner cone has purplish tint and
more pointed; loudest flame; used for welding copper and zinc base metals