REPARING OF TURBINE INNER CASE BY MANUAL METAL ARC WELDING

Abstract

The research consisted of performing the maintenance on the internal cover (shell) of the electric power generating unit turbine which was made of nodular cast iron that was achieved by replacing the damage part, with cast carbon steel, using manual metal arc welding, and AWS ENiFe-CI filler metal electrode. Pre-heating and post-heating were implemented to avoid the formation of brittle phase in the welded zone or Heat Affacted Zone (HAZ). The weldments mechanical tests showed that the welded zone mechanical properties were better than that of the original metal of the internal cover.