Boiler Construction, Design, and Installation
Domain 1 - Boiler Construction, Design, and Installation. The exam tests pressure-part identification, which ASME code governs a given boiler, and what must be completed before a new or altered boiler is fired in Michigan.
Pressure parts and code jurisdiction
The shell, drums, tubes, tubesheets, furnaces, and stayed surfaces are pressure parts. A boiler above 15 psig steam, or above 160 psig water, is a power boiler built to ASME Section I. A heating boiler at or below those limits follows Section IV. Installation must leave clearance for inspection and tube pulling, supply combustion air, and sit on a foundation sized for wet weight plus connected piping loads. Welding, rerating, or repairing a stamped pressure part requires an NBIC hold and an R-stamp repair; a contractor cannot simply weld a crack.
Before first firing
Plans and the manufacturer's data report are reviewed, the boiler is hydrostatically tested, and a state inspector must issue a certificate before the burner is lit. New Section I construction is tested at 1.5 times the maximum allowable working pressure (MAWP), with openings blanked and no leakage or permanent deformation. Safety valves, the gauge glass, and the low-water fuel cutoff must be installed and functional.
Worked example
A new firetube boiler is stamped 150 psig MAWP. Test pressure = 150 × 1.5 = 225 psig. The boiler is filled, capped, and brought slowly to 225 psig; a leak shows as a pressure drop, and a bulge or permanent set fails the test even if no water appears. The safety valve is set at or below 150 psig and must be removed or gagged only under a written hydro procedure.
Traps
Assuming the stamp pressure equals the safety-valve setting; treating a used or relocated boiler as exempt from inspection; confusing Section I and Section IV limits; firing to check it out before the certificate is issued.