US EPA

1758394 

Journal Article 

Repair welding of cracked shrouds in steam turbines 

Albert, SK; Gill, TPS; Bhaduri, AK; Iyer, DR 

1999 

863-872 

WOS:000166688900084 

The procedure for repair welding of cracked shrouds in steam
turbines has been developed using the gas tungsten are welding process and ER 316L filler wires.
The procedure development included selection of welding consumable, optimisation of post weld
heat treatment parameters, determination of mechanical properties of weldments in as-welded and
PWHT conditions, and selection of suitable method for local PWHT of repair welds. Three different
filler wires (ER 309L, ER 316L, and ER NiCr-3) were evaluated during procedure qualification. All
these filler wires were of austenitic type and were preferred over matching composition filler
wires to avoid preheating of the job and hydrogen induced cold cracking. This procedure has been
applied for repair welding of 8 cracked shrouds in 4 steam turbines of 3 Indian nuclear power
plants. The details of the procedure development and the experience of in-plant repair welding
are presented in this paper.