Automated Pulse-Mig Overlay Protects Boiler Nose Arch

IGS recently performed automated weld overlay on the nose arch of a large power utility’s Units 1 & 2, 640mw Foster Wheeler boilers. Unit 1 was accomplished in the fall. The quality of the work was at a level that we were the preferred vendor for the work on Unit 2 in the spring. The plant identified wastage from soot blower erosion in a 550 sf area within each unit. Tube thickness was between .140 and .200. The material of choice was ER70S-6 carbon steel. With previous vendors, the plant had experienced tube panel warping; thus it was critical for IGS to minimize heat transfer to the tubes. No water was in the tubes at the time of application. Working conditions were difficult at best, with the arch at a 45 degree angle and continuously falling fly ash from overhanging pendants. IGS successfully completed the project with no safety incidents, 90-100 mils of overlay with a single pass, zero blow-throughs, and no leaks upon start-up. For more information on IGS’ services to the Fossil Power market, click here.