Tweco Tri-Arc Serie - Manual (Page 10)

2-4
position gouging/cutting, or for heavy metal-removal operations using large elec-
trodes. High top work shoes provide adequate protection from foot burns. Use leather
spats for added protection. Do not use flammable hair preparations when gouging/
cutting. Wear ear plugs to protect ears from sparks.
2.05 Shielding Booths
Where the work permits, the arc welder should be enclosed in an individual booth
painted with a finish of low reflectivity—an important factor for absorbing ultraviolet
radiations—such as zinc oxide and lamp black. The welder may also be enclosed in
similarly painted noncombustible screens.
2.06 Fire and Burn Hazards
WARNING
WELDING SPARKS CAN CAUSE FIRES AND EXPLOSIONS.
Causes of fire and explosion include combustibles reached by the arc, flame, flying
sparks, hot slag or heated materials. Remove combustibles from the work area and/or
provide a fire watch. Avoid oily or greasy clothing as a spark may ignite them. Keep a
fire extinguisher nearby, and know how to use it.
Be alert to the danger of conduction or radiation. For example, if you will be gouging/
cutting on a metal wall, partition, ceiling or roof, take precautions to prevent com-
bustibles from igniting on the other side. Do not gouge/cut containers that have held
combustibles. Vent all hollow spaces, cavities and containers before gouging/cutting
to permit air or gases to escape. Purging with inert gas is recommended.
Table 2-1: Recommended Minimum Air Requirements
Type of Torch
Air
Pressure¹
psi (kPA)
Air
Consumption
cfm (L/min.)
Recommended Compressor Rating
Intermittent
Use
hp (kW)
Continuous
Use
hp (kW)
ASME
Receiver
Size
gal (lit)
K-5
80 (550)
25 (708) 5 (3.7) 7.5 (5.6)
80 (303)
Tri-Arc ® 33 (934) 7.5 (5.6) 10 (7.5)
¹ Pressure while torch is in operation.
Use only compressed air. Using combustible compressed gases can cause explosions
that may result in personal injury or death.