For efficient and economical fabrication, the choice of welding processes should primarily be based on productivity and cost factors, together with material and weld position considerations.
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Shielded Metal Arc Welding (SMAW)
Advantages
• Versatility - readily applied to a variety of applications and a wide choice of electrodes
• Relative simplicity and portability of equipment
• Low cost
• Adaptable to confined spaces and remote locations
• Suitable for out-of-position welding
Disadvantages
• Not as productive as continuous wire processes
• Likely to be more costly to deposit a given quantity of metal
• Frequent stop/starts to change electrode
• Relatively high metal wastage (electrode stubs)
• Current limits are lower than for continuous or automatic processes (reduces deposition rate)
Submerged Arc Welding (SAW)
Advantages
• Lends itself to the production of consistently high quality welds with minimum operator skills.
• Minimum of welding fume and of arc visibility (radiation).
• Well suited to welding thick sections.
• Suitable for welding carbon, low alloy and alloy steels.
• Relatively high metal deposition rates
Disadvantages
• Flat or horizontal position welding only
• Care required to preserve correct electrode alignment, as electrode
• Tip and weld pool are underneath solid flux cover
Flux Cored Arc Welding (FCAW)
Advantages
• Versatility - suitable for a variety of positions and applications
• Capable of relatively high deposition rates
• Enables “one process” operation for individual projects – simplifies training, supervision and logistics
Disadvantages
• Incorrect selection of consumables and parameters may lead to lower weld toughness
• Potential for lack-of-fusion type defects if welding parameters are incorrect or misalignment occurs
• Fume extraction may be required
Gas Tungsten Arc Welding (GTAW)
Advantages
• Applicable to a very wide range of materials.
• Especially good for welding thin sections and delicate workpieces
• Capable of producing welds of high quality and appearance
Disadvantages
• Generally restricted to flat or horizontal welding
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