COMMERCIAL BOILERS FINAL EXAM 2025 QUESTIONS AND ANSWERS

COMMERCIAL BOILERS FINAL EXAM
2025 QUESTIONS AND ANSWERS



A low pressure steam boiler has a MAWP of ____ psi.


a. 75


b. 35


c. 15


d. 50 - ANS c. 15




A horizontal return tubular (HRT) boiler is a ____ boiler.


a. firetube


b. watertube


c. scotch marine


d. none of the above - ANS a. firetube
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, Some watertube boilers are equipped with ____ to increase the heating surface and the life of

the furnace refractory.


a. stays


b. baffles


c. brickwork


d. waterwalls - ANS d. waterwalls




Watertube boilers were designed to operate at pressures as high as ____ psi, a point known as

the critical pressure of steam.


a. 512


b. 5000


c. 1015


d. 3205 - ANS d. 3205




Boiler tubes are manufactured using materials that meet ____ specifications.


a. DOE
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b. ASME
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, c. ABMA


d. ASTM - ANS b. ASME




The boiler superheater raises the temperature of the ____.


a. steam leaving the boiler


b. air for combustion


c. gases for combustion


d. feedwater - ANS a. steam leaving the boiler




At 0 psig, how many BTU are necessary to change one lb of water at 212 F into 1 lb of steam?


a. 1,190


b. 970


c. 144


d. 180 - ANS b. 970




Steam at 100 psi and 400 F is ____.
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a. wet



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, b. saturated


c. superheated


d. none of the above - ANS c. superheated




Increasing the pressure has what effect on the boiling point of water?


a. temperature will increase 2 F for every psi


b. temperature will be raised


c. temperature will be lowered


d. no change - ANS b. temperature will be raised




Heat may be transferred in how many ways?


a. one


b. two


c. three


d. four - ANS c. three
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A British thermal unit is ____.



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