Where is tack welding used?
Tack welding can happen wherever you perform any welding, but you'll see specific types used more in particular industries. For example, you'll find large bridge and hot tacks more frequently when working with structural steel, as in fabrication shops and building construction.
You're unlikely to see much hot tacking in TIG welding because the lighter gauge material involved would not tolerate a good beating. However, since thinner stainless is susceptible to heat distortion, smaller tacks are used to help stay within the tight tolerances on blueprint
Although all types of welding employ tack welding, sometimes it's not practical. Tacking typically eliminates the need for fixtures, but some industries find it more efficient to use them. For instance, companies fabricating dozens of one type of weldment each day will choose machined fixtures over tack welding to hold tighter tolerances and be more productive.
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