Steam Boilers and Engines Questions

• Difference between Cornish and Lancashire boilers Which statement correctly differentiates the Cornish boiler from the Lancashire boiler with respect to the number of main flue tubes?
• Purpose of an air preheater in a boiler system An air preheater in the flue-gas path primarily serves to:
• Simple vertical boiler detail In a simple vertical boiler, the water tubes (cross tubes) are generally arranged as:
• Locomotive boiler steaming rate State whether the following is correct: A locomotive boiler is designed to produce steam at a very high rate to meet rapid traction demands.
• Boilers with and without forced circulation In which of the following boilers does forced circulation of water not take place?
• Cochran boiler orientation check State whether this statement is correct: A Cochran boiler is a horizontal multi-tubular boiler.
• Typical length of a Lancashire boiler shell Select the usual industrial range for the overall shell length of a Lancashire boiler (excluding external fittings):
• Boiler Accessories — Identification and Function In steam power-plant practice, which of the following items are classified as boiler accessories (i.e., performance-enhancing external devices, not mandatory safety mountings)?
• Forced-Circulation Steam Boilers — Purpose of the Applied Force In a forced circulation steam boiler, for what purpose is external mechanical force (via pump) applied to the working fluid?
• Steam Generation Terminology — Evaporation per Kilogram of Fuel The quantity of water evaporated (in kg) per kilogram of fuel burned in a boiler is commonly called what?
• Compounding Expansion in Steam Engines When the expansion of steam is divided among two or more cylinders (compounding), how is the overall ratio of expansion affected compared with a single-cylinder engine?
• Diagram Factor — Typical Range in Practice What is the typical average range of the diagram factor (ratio of actual to theoretical indicator diagram measures) for steam engines under normal operating conditions?
• Boiler Type Identification — Fire-Tube Example Which one of the following is a fire-tube boiler (hot gases through tubes, water around tubes)?
• Fire-Tube Boilers — Practical Pressure Limit Fire-tube boilers are generally limited to a maximum safe working pressure closest to which of the following values?
• Locomotive Boiler — Superheater Flue/Tube Size In a typical locomotive boiler, the approximate outside diameter of the large superheater flue (that houses the superheater elements) is closest to:
• Steam Engine Governing Methods — Throttle vs Other Types When engine speed is controlled by a valve in the main steam pipe that regulates the pressure of steam entering the cylinder, the method is called:
• Piston Speed Comparison — Single-Acting vs Double-Acting Engines For the same stroke length and the same crankshaft speed, the mean piston speed of a double-acting steam engine is __________ the mean piston speed of a single-acting steam engine.
• Steam condenser terminology — define the index for quality of vacuum In steam power plant practice, the ratio of the actual vacuum obtained in a condenser to the ideal vacuum (corresponding to saturation pressure at the condensing temperature) is called what?
• Chimney draught at maximum discharge — compact formula (mm of water) For a chimney of height H (metres) with outside air absolute temperature T1 (K), the draught required (in mm of water) for maximum discharge of flue gases is given by which relation?
• Compound engines — torque smoothing and flywheel sizing A receiver-type compound steam engine (with cranks typically at 90°) requires a lighter flywheel compared to a single-cylinder engine. Is this statement correct?