Inspection of Tube-End Support Casting and Hanger Supports
The tube-end supports are usually of cast material, ribbed for strength, and insulated on the fire side. They support the tube ends and the headers and protect the headers from direct contact with the high furnace temperatures. Close inspection of the insulation is important because failure of the casting will occur quickly if the high temperatures of the firebox reach it. If exposed areas are found, examine the metal for deterioration and the bolting for failures.
Check the castings for positioning and be sure that the tubes are free to expand without binding.
The intermediate tube supports are made of heat resistant alloys. These fail from constant exposure to high furnace temperatures, flame impingement, and forces exerted by movement of the tubes. The intermediate tube supports should be inspected for general deterioration by excessive heat, for cracking, and for adequate support of the tubes.