Electroslag welding

From GAWDAwiki

Electroslag welding is a welding technique in which heat is generated from the resistance of molten slag to an electric current passing through it.

The Electroslag Welding Process

Before welding begins, the gap between two vertically-positioned metal pieces is filled with flux. An arc is then struck between an electrode and the work-piece. The resulting heat melts the flux, forming molten slag. The electric current running through the molten slag allows it to maintain its liquid state.

When the slag reaches a temperature of approximately 3,500°F (1,930°C), the consumable electrode and work-piece edges melt. Metal droplets are deposited into the weld pool, joining the pieces.

Benefits of Electroslag Welding

• High deposition rate
• Minimal distortion
• Little slag consumption
• Able to join metals of any thickness

Risks of Electroslag Welding

• Coarse grain structure and poor toughness of weld
• Only possible in vertical positions^[1]

References

1. http://www.substech.com/dokuwiki/doku.php?id=electroslag_welding_esw