Page 93 - Module DMV20173

5. 0 JOINING PROCESSES

7. Figure 5.2 shows the schematic illustration of SMAW.

Figure 5.2 Schematic illustration of SMAW.

Example 5.1

Describe the characteristics of Shield Metal Arc Welding (SMAW).

Solution:

Process characteristic:
1. Uses a consumable rod electrode.
2. Deposits slag on the weld bead.

3. Provides shielding by vaporization of the flux coating on the electrode.
4. Supplies constant welding current.0
5. Weld appearance and quality depend on operator skill in maintaining a constant arc
length and travel speed.

5.2.3 SUBMERGED ARC WELDING (SAW)

1. Submerged arc welding uses a bare metal wire electrode.

2. The arc is protected by a separate supply of loose flux, some of which melts and
forms a slag cover over weld.
3. During welding, the bare metal wire electrode is fed automatically into the blanket of

flux.
4. There are minimal fumes, no visible arcing and the equipment is easy to use.
5. Submerged arc welding is popular in the heavy metal fabrication industry because it
gives welds of high quality.
6. It is used to make pipes, pressure vessels, boilers, tankers and other structures that

require welding in a straight and continuous line.

BPLK 125 DMV 20173