advantage and disadvantage

Electroslag Welding (ESW) deposits the weld metal into the weld cavity between the two plates to be joined. This space is enclosed by water cooled copper dams or shoes to prevent molten slag from running off. The weld metal is produced from a filler wire that forms an initial arc with the workpiece until a sufficient pool of liquid metal is formed to use the electrical resistance of the molten slag.(i) Joint preparation is often much simpler than for other welding processes.
(ii) Much thicker steels can be welded in single pass and more economically. Thicknesses up to 450 mm in plain and alloy steels can be welded without difficulty.
(iii) Electroslag welding gives extremely high deposition rates.
(iv)Residual stresses and distortion produced are low.
(v) Flux consumption as compared to that in submerged arc welding is very low.
(vi)During the electro slag process, since no arc exists, no spattering or intense arc flashing occurs.
Disadvantages
(i) Submerged arc welding is more economical than electroslag welding for joints below 60 mm.
(ii) In electroslag welding, there is some tendency toward hot cracking and notch sensitivity in the heat affected zone.