745 Welding, Cutting, and Brazing Safety

Brazing Safety

Brazing is a metal-joining process in which two base metals are joined by heating them above 450°C (840°F), but below their melting points.

A filler metal (such as brass, bronze, or silver alloy) is melted and drawn into the joint by capillary action, creating a strong, permanent bond when cooled.

Equipment includes: Brazing torch (oxy-acetylene, propane, MAPP gas), filler rods (bronze, brass, silver alloys), flux, torch tip cleaners, strikers, and flint lighter.

Operation Steps: The following is a brief list of steps to safely operate the equipment:

1. Inspect Equipment
   • Check torch, hoses, regulators, and cylinders for leaks or damage.
   • Ensure cylinders are upright and secured.
   • Verify you have the correct filler metals and flux for the job.
2. Set Up Gas Supply
   • Open fuel gas (acetylene, propane, or natural gas) cylinder valve slowly.
   • Adjust fuel gas regulator to proper pressure.
   • Open oxygen cylinder valve slowly (if used).
   • Adjust oxygen regulator to proper pressure (if using oxy-fuel torch).
3. Purge Hoses
   • Slightly open fuel gas valve on the torch to purge air, then close.
   • If using oxygen, slightly open oxygen valve to purge air, then close.
4. Light the Torch
   • Open fuel gas valve slightly on the torch.
   • Use a striker to light the flame (never use a lighter or match).
   • If using oxygen, adjust oxygen valve to create a neutral flame (balanced fuel and oxygen).
5. Perform Brazing
   • Heat the joint area evenly until the base metal reaches brazing temperature.
   • Apply filler metal to the joint—let the heat draw it in (capillary action).
   • Move the torch to maintain even heating.
6. Shut Down
   • Close fuel gas valve on the torch first to extinguish the flame.
   • Then close the oxygen valve (if used).
   • Close cylinder valves: fuel gas first, then oxygen.
   • Release regulator pressure by opening torch valves—oxygen first, then fuel gas—then close the torch valves again.
   • Back out regulator screws to release tension.

Safe Operation Guidelines: The following safe procedures and practices help prevent brazing injuries and illnesses:

• Wear goggles, gloves, and protective clothing. Protective gear shields the eyes, hands, and skin from sparks, heat, and molten metal during brazing operations.

• Keep flammable materials away. Sparks and heat from brazing can easily ignite nearby flammable items, so the work area must be clear of such materials.
• Regularly check hoses and equipment for leaks. Inspecting gas hoses, torches, and connections helps detect leaks early and prevent fires or explosions.
• Keep a fire extinguisher accessible. Having a working fire extinguisher nearby allows for quick response if a fire starts during brazing work.

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