Oxy Fuel Cutting Systems Basic Setup Use

Oxy Fuel Cutting Systems Basic Setup & Use Tim Turner

Typical Torch System n Oxygen Cylinder n Acetylene Cylinder n Method of Securing the cylinders n Caps n Regulators n Backflash arrestors n Hoses n Torch Body n Torch Head n Torch Tip n Clothing and Eye/Face Protection

Oxygen Cylinders n n n n Oxygen is very pure - 99% Pressure is about 2200 psi at 700 F Hydrostatic tested to 3300 psi Forged from a single piece of steel no welding Minimum of 1/4” thickness Annealed periodically Stored away from combustibles – – 5’ high wall 1/2 hour fire rating

Oxygen cylinder sizes: T K LK S D, E, Y, U, LE Q ME MBE XAD MD R

Liquid Oxygen is stored in a dewer flask

Acetylene Cylinders n n n n Acetone - absorbs acetylene under pressure Consumption rate = 1/7 content per hour Fusible plug - 2120 F Temperature has an extreme affect on pressure Let stand upright at least 20 minutes before using Protected valve or cylinder cap Stored away from oxygen and combustibles – – 5’ high wall 1/2 hour fire rating

WK WS WTL WC WQ

Acetylene Cylinders n n n n n C 2 H 2 - Made from calcium carbide and water Welded construction Monolithic filler - Asbestos fibers, balsawood (85% porus) Acetone - absorbs acetylene under pressure Fusible plug - 2120 F Consumption rate = 1/7 content per hour Temperature has an extreme affect on pressure Let stand 20 minutes before using Protected valve or cylinder cap Sold by cubic feet - determined by weight of the cylinders

Oxygen Cylinder Valve Brass Construction n Double back seat - NEVER LEAVE HALF OPEN n Pop off valve - (fragile disk) n Right hand Thread n

Acetylene Cylinder Valve Brass Construction n Packed valve - OPEN 1/2 TO 3/4 TURN n Hand wheel or tank wrench - NEVER REMOVE WRENCH during use n RH (Male) or LH (Female) Thread n

Manifold Systems Increased Efficiency n more stations n no downtime n

Parts: Cylinders n Hoses - Brass or braided n Check valves or hand valves n Flashback Arrestors - OSHA n Regulators n Main valves n

Procedure for changing tanks: Continuous supply of gasses n Do not allow empties to be pressurized n Valves and/or checkvalves n Never unsecure cylinders without protective caps n Check for Leaks n MT - DATE n

Regulators n n n Gauges - High and Low pressure Bonnet - weakest point Adjusting screw - Clockwise = On

Regulators n. Single stage - less expensive n. Dual stage - more accurate - lump on back - 200 psi n. Nozzle Type - low volume n. Stem type - High Volume n. Gauges - High and Low pressure - bourbon tube n. Bonnet - weakest point n. Adjusting screw - Clockwise = On

Protector Cap Protects valve from being knocked off n Must be in place when Regulators are off n

Backflash Arrestor Torch / Manifold n Regulator / torch n

Hoses n Acetylene = Red – n Oxygen = Green – n Notch around nut means LH thread RH Thread New Hoses have talc inside - Blow out before connecting to torch

Needle valves What each does n Preheat / Cutting hole pressures n Tightening n

Torch Body n single stage / dual stage

Cutting Head Preheat oxygen needle valve n Seat type / Graphite type - tightening n Body to head connection - tightening n Oxygen lever - regulator setting, #1 needle valve setting n

Cutting Tips 1 or 2 piece n sizes relate to # Drill Sizes n Hand / Wrench tight n Rosebud

Tip Cleaners

Acetylene safety Precautions Never call acetylene “gas” n Extremely explosive with air or oxygen n Leave wrench on tank n

Oxygen Safety Precautions Never call oxygen “Air” n Never allow oxygen to come in contact with oil, grease, or other petroleum bases n Never use oxygen for compressed air n Never move cylinders without caps n Always secure cylinders n

• Setup Procedures for Oxy. Acetylene Systems n n n n Do not move cylinders without valve protection Secure cylinders Inspect threads “Crack” Oxygen Valve Attach regulators and tighten Blow talc from new hoses Attach Flashback arrestors, check valves, hoses, check valves, torch body, torch head, and tip Properly pressurize torch and check for leaks

Procedures for Lighting Oxy. Acetylene Systems n n n n n SCREW ADJUSTING SCREW OUT Stand to the side of the adjusting screw Open tanks one at a time (Oxygen wide, Acetylene 1/2 turn) Adjust regulators Bleed lines one at a time Fine adjustments made while bleeding the hoses Open the acetylene needle valve and light torch Open high pressure oxygen needle valve wide Adjust to a neutral flame

Shut Down Procedure for Oxy. Acetylene Systems Turn off acetylene needle valve n Turn off preheat oxygen needle valve n Turn off tanks n Bleed lines one at a time n TURN ADJUSTING SCREWS OUT n Turn off all needle valves n

Flame types Carborizing Neutral Oxidizing

Starting or restarting a cut Resume Cutting hole Heat the starting point off the edge Move the oxygen of the plate and start the oxygen stream

Offhand Cutting Techniques n Rolling your hands – – n “Pre-load” your wrist and forearm Roll, don’t slide for a smoother cut Sliding the torch through your fingers – – – Apply pressure to torch tubes with thumb and index finger Keep other three fingers in fist Don’t move the torch body hand during stops and starts.

Beveling Angles Slide the torch through your fingers toward you. n Only move the hand nearest the flame when continuing the cut. n Keep your other three fingers in your fist. This will keep your hands cooler and allow you to make a better cut. n

Safety n Backflash – n Turn Oxygen off first Watch where you cut – – Don’t blow molten metal toward another person Don’t melt the hoses Don’t drop metal on hoses Don’t let hoses lay on hot metal

Headgear Assembly – Forehead pad – Proper adjustment – How to assemble – How lenses go in – Cleaning different types of lenses – Autochange hoods – Shade numbers for various things – Cracked or broken hoods – Hood designs (pipeliner, short, sock, brazing shield, handheld).