Question 215Steam Plants - Assistant Engineer

The correct answer is D) single-pass, fire-tube, scotch marine. The illustration MO-0064 depicts a single-pass, fire-tube, scotch marine boiler. This type of boiler is characterized by the hot gases from the fire passing through the boiler tubes, heating the water surrounding the tubes in a single pass, before exiting the boiler. This design is commonly found on smaller vessels and is classified as a fire-tube boiler. The other options are incorrect because forced circulation, coil-type boilers have a different design, two-pass, scotch marine boilers have a different flow pattern, and two-pass, water-tube boilers use a different construction method.