•A welder’s hat will prevent both radiation burns to the head and hot sparks, falling slag, and hot metal burns.
•High-top boots can prevent hot sparks and slag from burning your feet.
•Never weld with pant cuffs; sparks falling into cuffs will burn pants.
•Make sure your welding gloves are dry and have no holes.
•Keep hands and body insulated from both the work and the metal electrode holder.
•Do not change the polarity switch position while the machine is under welding current load.
•Welding machines must be turned off when not attended.
•Do not stand on a wet surface when welding to prevent electric shock.
•Welding cables and electrode holders must be inspected for broken insulation regularly to prevent electric shock.
•Welding power supplies on AC lines must be properly grounded and emergency shut-off switch location known and accessible.
•Welding area must be dry and free of flammable materials.
•Protect your ears from welding and grinding noise with ear plugs or ear protectors.
•Any compressed gas cylinders must be properly secured and out of the spark stream.
•Avoid wrapping welding cable around your arm or body in case a vehicle snags the cables.
•Never cut or weld on containers without taking precautions.
•In shielded metal arc welding, the welder must plan for disposal of electrode stubs: they are hot enough to cause burns and to start fires and must not be dropped from heights because of the hazard to others.
Basic Safety Equipment
Figure 2-14 Here’s a sample of safety equipment. From top left going clockwise: goggles worn under welding helmet; welding caps to be worn under helmet; welding jacket; and gloves
Photo courtesy of Lincoln Electric and Hobart Welders.
Table 2-3 Recommended lens shade by amperage and welding process
courtesy of Hobart Welders.
Auto-darkening Faceplates
An electronic faceplate or lens is one of the most recent and important safety devices developed in the welding industry. These devices are designed to be clear, or nearly clear, then darken the instant arc is established; when purchasing be aware of the time the lens takes to darken 1/25.000 of a second or faster is recommended. Advantages of auto-darkening faceplates include:
•The welder does not need to raise and lower his helmet when performing a series of welds: he can always see where he is with the helmet down.
•The beginner does not have to master holding his electrode steady when he drops his helmet. This permits beginners to perform better welds earlier in their training.
•Electronic faceplates offer continuous eye protection from infrared radiation coming off red-hot metal even when they are not in the darkened mode. It is just easier on the eyes and the welder is less likely to incur eye injury from inadvertent arc strikes.
Figure 2-15 Auto-darkening faceplates darken almost immediately as soon as the arc is established
Photo courtesy of Hobart Welders.
Oxygen and acetylene gases when combined, in the proper proportions in the torch handle’s mixing chamber, produce an approximately 5,600°F (3,100°C) flame at the torch tip. This flame melts the edges of the base metals to be joined into a common pool. Sometimes additional filler metal is added to the molten pool from a welding rod. When this common pool cools and the metal freezes solid, the joined metals are fused together and the weld complete. Other fuel gasses can be used in place of acetylene—and often are for soldering or brazing—but their maximum heat potential is below the heat output required for welding steel. The American Welding Federation (AWF) uses the abbreviation OAW for oxyacetylene welding.
WHAT ARE THE APPLICATIONS THAT OAW IS BEST SUITED FOR?
WHAT METALS CAN THE OAW PROCESS READILY WELD?
WHAT ARE SOME BASIC SAFETY PROCEDURES?
WHAT TYPES OF EQUIPMENT ARE NEEDED?
HOW DO YOU SELECT FILLER METAL (WELDING ROD)?
HOW IS THE EQUIPMENT SET UP?
WHAT ARE THE SPECIAL PREPARATIONS FOR WELDING?
HOW ARE WELD RESULTS ACCESSED?
WEST COAST CUSTOMS WELDING TIPS
OXYACETYLENE WELDING TIPS FROM WEST COAST CUSTOMS
Figure 3-2 OAW does not require electrical power, so it is extremely portable.
What are the applications that OAW is best suited for?
If you have many different types of projects or repairs, OAW processes work well, particularly if you are not near an electrical power source. Unlike other welding processes, OAW does not require electrical power. Use it for welding thin sheet, tubing, and small-diameter pipe.
Pros and Cons of OAW Process
Advantages
•Low cost
•Readily portable
•Excellent control of heat input and puddle viscosity
•No external power required
•Good