Overview of Submerged Arc Welding (SAW) Ⓡ

 SUBMERGED ARC WELDING (SAW)

1. How it works: Usually automatic, but can be semi-automatic.

2. Working principle: Granular flux and bare solid wire are used. Since the Ark is submerged in water, there are no visible traces of the Ark. The arc melts the electrode wire, flux, and some base metal, forming a weld puddle.

3. Basic equipment requirements:

1. Transformer/rectifier (constant voltage characteristics (flat))
2. Head/hose assembly
3. Power return cable
4. Wire feeding unit
5. Flux hopper/supply/recovery system
6. Run power tab
7. Tractor trolley
8. Smoke extraction.

4. Arc ignition: Wire contact is made by advancing the wire through a mechanical drive.

5. Arc and weld protection: Granular flux is used to generate shielding gas and slag and add alloying elements to the weld pool.

6. Purification and cleaning of welds: Purification and cleaning of flux joints 7. Process variable parameters:

a) OCV (Open Circuit Voltage): Required to start or reignite the arc. b) Arc voltage: Varies with arc length. The arc is soaked. Changes in arc length affect the composition of the weld metal.
c) Current / WFS (Wire Feed Speed): Increasing the wire feed speed automatically increases the current in the wire.
d) Polarity: AC/DC +/-.
e) Flux type and size: (i) Molten flux: acidic type. (ii) Cohesive flux (combined flux): Basic type. The shape of the flux is granular
f) Type and diameter of electrode wire: High-quality wire with coil diameter 2.4mm to 6 mm. The larger diameter reduces penetration power.
g) Electrode wire/flux specifications: Select the composition and grade depending on the electrode and base material.
h) Wire Feed Speed ​​(WFS): Rising the wire feed speed spontaneously increases the current in the wire.

8) Consumables: High-quality drawing wire and granular flux.

i) Typical weld defects: Centerline cracks: deep, narrow welds.
(ii) Voids: caused by weld depth/width ratio > 3/2.

9) Advantages – a) High productivity b) No visible arc light

10) Disadvantages a. Limited position welding
b. Variable composition (arc length)
a) - Typical weld defects: Centerline cracks: deep, narrow welds.
b) - Voids: caused by weld depth/width ratio > 3/2.
Position options: Flat only, but possible H/V butt weld.

Note: This section features several affiliate links, meaning we will earn a small commission if you purchase through these links...