8.1. Economical Suggestions

8.1.1. Why is welding preferably done in the flat position?

In the flat position, the base metal provides support for the molten pool of weld metal. Therefore, this position provides for the fastest deposition rate and the most economical weld. Welding in the horizontal position is similar, but slightly less efficient. Welding in the vertical or overhead position requires slower deposition rates to maintain the integrity of the molten pool against the effects of gravity.

last modified 13 September 2002

8.1.2. Why is use of the least possible size fillet weld desirable?

Because the volume of weld metal in a fillet weld is proportional to the square of the weld size, a 1/2-in. fillet weld uses four times as much weld metal as a 1/4-in. fillet weld of the same length. Because the cost of welding is essentially proportional to the volume of weld metal, the most economical fillet-welded detail will result when the least possible fillet weld size is used. Accordingly, it is common practice in welded joint design to select fitting and weld length to minimize fillet weld size, when possible. Additionally, smaller welds reduce the possibility of warping and distortion due to heat input.

last modified 13 September 2002

8.1.3. Why are fillet welds preferred over groove welds?

Fillet welds generally require less weld metal than groove welds. Additionally, fillet welds do not generally require beveling and similar base metal preparation. As a result, fillet welds are generally more economical to make than groove welds. Thus, fillet welds are preferred.

last modified 13 September 2002