The No. 28 Repair Project continues to move forward. Largely, staff and volunteers have been working to remove corroded staybolts in order to replace them. Dye penetrent testing of the tube sheets is also being done, which helps to visually assess damage to the tube sheets.
Project staff member Norman Comer uses a torch to burn out a corroded staybolt where it meets the boiler.
Interior of the firebox. The holes on the top right are from where stay bolts were removed.
Stay bolts that have been removed for replacement, due to thinning.
Project Volunteer David Ethier recently conducted a dye penetrant test on the front tube sheet. Here, he first applies a specially formulated red dye.
Ethier allowed the dye to sit on the tube sheet for 30 minutes before thoroughly removing it from the surface. The dye will be left behind in cracks, pits, and other porous spots only.
Next Ethier sprays on a developer, which appears white when applied, but develops the red dye left behind in cracks and pits, making them easy to spot visually.
Here you can easily see a small crack in the tube sheet, highlighted by the red dye. Cracked areas will be repaired by grooving out the damaged material and welding in new.
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