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SMAW “STICK”
SMAW or Shielded Metal Arc Welding is one of the most versatile methods of welding. SMAW can be done using AC or DC power and can be effective in almost any weather conditions. In this method a consumable electrode or “stick” is used to form the weld. A flux coating on the electrode will melt and float to the top of the molten pool forming a slag, protecting it from oxygen and other atmospheric contaminants. Slag also controls the rate of cooling allowing for a high deposit rate without causing a brittle weld. This slag should be chipped off and cleaned before running a new pass or painting. Some types of electrodes have excellent cleaning properties and can be used on dirt or rusty metal, although it is always a good thing to clean the area if possible. |
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GMAW “MIG”
GMAW or (Gas Metal Arc Welding) also known as “MIG” welding (Metal and Inert Gas), is a high deposit user friendly method of welding. A filler wire is used to form the weld. This wire is fed from a spool by a set of 2 or more drive wheels. The wire feed rate can be set to match the speed at which the wire melts. The weld puddle is protected by shielding gas and is therefore susceptible to wind. Even a light gust of wind can cause porosity (many small bubbles) and a weak weld, and so MIG welding must be done inside or at least in a sheltered area. MIG welding should be done on a clean surface free from paint and rust. There is no slag to clean or electrodes to change and so multi pass welds and long seams are quicker with MIG than with SMAW “Stick” welding. |
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FCAW “Flux Core”
FCAW (Flux Core Arc Welding) is similar to GMAW (MIG). A tubular wire with a flux core is fed through a set of 2 or more drive wheels to a “gun” at the rate that the wire melts. The weld is shielded by the slag formed by melted flux as in SMAW (Stick) but may also be shielded by a gas as in MIG welding. Using only the slag as a shielding method is referred to as “gasless” Flux Core. |
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GTAW (TIG)
GTAW (Gas Tungsten Arc Welding) or “TIG” (Tungsten and Inert Gas) is a precise method of welding. In this method a non-consumable electrode made of tungsten is used to transfer an arc to the work piece. The heat of the arc melts the work forming a small molten puddle. Filler metal is fed into the puddle by hand and is protected by a shielding gas. TIG welding can create an extremely localized heat affected zone that allows it to be performed on thin metal without melting through or warping. As with MIG and Dual Shield Flux Core, TIG welding must be done under protection from the elements and wind. TIG allows for a high level of control and takes a high level of skill to perfect. This method is used primarily for delicate work, exotic metal (such as stainless and chrome) and in pressure piping and is rarely used in heavy fabrication. |
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WELDING |
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The 4 most widely used methods of welding today are SMAW(stick), GMAW(mig), FCAW(flux core) and GTAW(tig). We offer and have extensive experience in all of these methods. |
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The advantage to this method is that it is nearly as resistant to wind and weather as SMAW (Stick) with the similar ease of welding and speed of MIG. A special “gasless” flux core wire must be with this method. Using both slag and gas as a shielding method is referred to as “Dual Shield” welding. Because of the slag cover, continuous wire feed and excellent weld puddle protection this method allows for a very high deposit rate and is used primarily for large fabrication. Like MIG welding, Dual Shield Flux Core welding must be protected from wind and weather. |