BOILERS

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The function of a boiler in the steam cycle is to convert water into steam. Reliability in operating naval boilers and associated equipment is important for the power plant to operate at maximum efficiency. The complex design of naval boilers requires a high degree of technical knowledge and skill on the part of the fireroom personnel responsible for boiler operations. All engineers should have some knowledge of the principles of combustion, how combustion occurs in a boiler, and the combustion requirements for operating a boiler more efficiently. You may want to review combustion in chapters 2 and 3 of this textbook. This chapter describes boilers commonly used in propulsion plants of naval steam-driven surface ships. This information is general in nature and does not relate to any one class of ship. Chapter 221 of the Naval Ships’ Technical Manual is the basic doctrine reference on boilers. For detailed information on the boilers in any particular ship, consult the manufacturer’s technical manuals furnished with the boilers. Upon completion of this chapter, you will have the knowledge to be able to identify and understand boiler terminology, the basic types of naval boilers and their operating principles, interpret gauges and indicators that aid in monitoring operating parameters of naval boilers, and understand boiler construction. You should be able to identify the major parts of a boiler and its functions. Also, you will learn about safety precautions that must be observed during boiler light-off.

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