Inspection of Furnace Setting and Appurtenances
Note the condition of the weather roof steelwork and sheeting. Check the roof for proper drainage.
Inspect the furnace steelwork for corrosion and distortion. Check the ties at the top and bottom of the buckstays. Check the side coil support bolts. Note the condition of all outside furnace walls for settling, bulging, cracking and the condition of the expansion joints.
Check for holes from inside the firebox with the lights out.
Check the condition of the burner openings, access openings, and the explosion doors. If explosion doors are bricked, bricks must be laid in loose.
Inspect the header compartments for the condition of insulation, if any, for alignment of the support castings, and for cracked or broken welds. Check the condition of doors, hinges, locking bars and latches, and steam smothering inlet nozzles. Be sure that the steam smothering inlet nozzles do not impinge directly on the tube headers.
Inspect the supporting members of walks and stairs and the condition of the floor plates or grating, handrails, and the boards. Look particularly for broken welds and attachments due to temperature change and movement of the structure.
Inspect the burners and their mountings for oxidation, cracks, overheating, and distortion. Examine the gas burner openings for oxidation, and for scale and plugging from foreign matter.
Inspect all fuel gas, fuel oil, steam smothering, and other associated piping for leaks, adequate thickness, and for conformance with material and safety requirements.
Always check that fuel gas lines and steam smothering manifolds are blinded, the valves chained, drains open, or that the lines are disconnected and pulled apart when working in furnaces, their header boxes, breaching or stacks.
Flue ways should be internally inspected, especially for accumulations of brick, ash, or combustion deposits that may restrict the flow of gases. Flue ways should be kept clean for proper furnace operation. Leaks should be patched or repaired.
Dampers in flues, ducts, or stacks, must be freely operable. Inspect the shaft and vane for distortion, warpage, or oxidation, and for freedom of movement in sides or bearings. Inspect the control mechanism or cables for general condition and ease of operation.
Air preheater tubes and tube sheets should be inspected for evidence of burning or oxidation, leakage, and for fouling with ash or scale. Look at the tube sheets for warping and for cracked or broken ligaments. Preheater tubes may be air tested for leaks. Leaking tubes are sometimes plugged off with insulation material.
On rotating air preheater units, check the condition of the peripheral and radial seals. Make certain both tension and clearances are to manufacturing specifications. Baskets, frames and drive system should be examined for fouling, deterioration, alignment, etc., to ensure efficient operation.