Re: RGS 20

We had the patch rolled at a local shop. I designed the patch on CAD and the fabricator used a program to cut the proper shape before rolling. We allowed about a foot excess on either end and about 1/2 to 3/4 inch excess longitudinally. We had to build dies so we could put the kinks in the end to line up with the existing courses. I am not exactly sure how long it took to roll the sheet but it took two of us about 50-60 hours to form and fit the sheet to the point shown in the photos.

This was probably the most difficult piece on the boiler to make. We have made just about every other piece but never one of these. If we were to weld the circumferential seams the job would have been easier but we needed to keep the rivet circ seam because of the remainder of the 2nd course being riveted. The 2nd course long seam disappeared since it was part of the damaged area. When done there will be no long seam which will give an efficiency of 1 so the MAWP (max allowable working pressure) will be considerably higher for the 2nd course.