3rd Stationary Engineer A B Test || Already Passed.

AB 6. 3 types of heat transfer correct answers Radiant heat - Transmitted from hot body to a cold body by means of direct radiation Co A 7. What is a combustion chamber? correct answers The area of the boiler where the complete burning of fuel occurs. B 8. What is an internally fired boiler and 4 types correct answers Internally fired boilers have the grates and combustion chamber enclosed within the boiler shell. Scotch Marine Vertical Fire Tube Locomotive Cast Iron Package B 13. Name 2 ways to support and take care of expansion in a HRT boiler. Which way is best? correct answers It can be set on saddles equipped with rollers to permit movement of the boiler as it expands and contracts. It may also be suspended from hangers and supported by overhead beams. Hanging by beams is best, puts no hardship on furnace walls. B 14. What is a longitudinal Joint? What is a circumfermential joint? correct answers A longitudinal joint is a seam running the length of the shell and it is butt strapped or fusion welded. It is above the fire line to avoid overheating. Lap joint running the circumference of the drum. B 17.Describe a scotch marine boiler and how its fired correct answers It is an internally fired self contained horizontal return fire boiler. It is a cylindrical shell containing the combustion chamber and tubes that are surrounded by water. B 19. Describe the circulation of water within a Stirling boiler. correct answers feed water enters the top rear drum, passes down the rear tubes to the mud drum. steam and boiler water go up the front and center tubes to the front and center drums. CIRCULATING TUBES allow boiler water to pass between the drums. what does not go out as steam, goes back down the rear tubes. B 23. What type of stays are used in a wet back scotch marine boiler. correct answers Stay bolts and through stays. These sometimes will have a telltale drilled in them. B 25. What is a super heater? What are the advantages? correct answers A bank of tubes through which only steam passes through without raising pressure. Advantages: increased efficiency of boilers, delivering drier steam. Drier steam can be transmitted long distances with minimal heat loss. With drier steam condensation and corrosion are reduced.