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[MW:11963] Repairs of submerged arc Furnace Roof secn. of SS-321 material

Respected All,
Our33 MVA Submerged Arc Furnace Roof comprises of 12 nos. water cooled
sections of SS-321 materialat MEL. These sections are prefabricated
and positioned on roof along with refractory lining.These sections are
located near the electrodes and are subjected to furnace gas
temperature of300 – 350oC. The section is trapezoidal with top &
bottom plate of 8 mm & 12 mm thickness respectively. The height of the
section along the peripheryis300 mm.
These sections normally give 3–4 yrs.trouble free service and after
that cracks are observed longitudinally from the bottom part of the
section at the root of the welding joint near to electrodes.
Presently we are carrying out repairs usingAWS, A5.4 : 308 L –
16 (size: 3.15 mm) of SUPERON brand SS welding rods. It is
observed that during in-situ welding in-citu (in some places SS-321
with IS:2062 plate) ,the condition of cracks propagate further.
Welding is required to be carried out repetitively and takes long time
for repairs.
The drawings of section do not specify the welding electrode to be
used and method/ procedure for carrying out welding.
We solicit your kind advice in above matter so that proper welding
methodology can be applied in repairs for increasing the life of roof
sections.
With kind regards,

Anil Barik
Rourkela

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