Steam Boilers and Engines Questions

• Boiler Fittings — Identify the Item That Is NOT a Mounting Which of the following is not a boiler mounting (i.e., not a safety/operational fitting fixed to the boiler shell)?
• Boiler Draught — Identifying Induced Draught A fan located at or near the base of the chimney reduces the pressure at the fuel bed below atmospheric to draw gases through the furnace. What is this type of draught called?
• Selecting a Steam Boiler — Key Determinants The choice of steam boiler type and size primarily depends on which of the following factors?
• Mechanical Draught — Effect of Smoke on Draught Level How does the level of mechanically produced draught (fan-based) vary with the amount of smoke in the gases?
• Artificial Draught — How It Is Produced Artificial (mechanical) draught in boiler practice is produced by which of the following?
• Steam Engine Geometry — Definition of Cut-Off Ratio What is the name given to the ratio of the cylinder volume at cut-off to the swept (stroke) volume?
• Boiler Performance — Factor of Evaporation (Unit Basis) If the total heat of steam is h kJ/kg and the sensible heat of feedwater is hf1 kJ/kg, what is the factor of evaporation (based on conversion to dry saturated steam at 100°C)?
• Steam Condensing Plant — Essential Components Which of the following components are required for a working steam condensing plant?
• Boiler fittings — purpose of the blow-off cock In steam-boiler practice, what is the primary function of the blow-off cock (blowdown valve) fitted at the lowest point of the shell or drum?
• Lancashire boiler — classification check State whether the Lancashire boiler is correctly described as a stationary, fire-tube boiler.
• Babcock & Wilcox boiler — classification check Verify the statement: “A Babcock and Wilcox boiler is a stationary water-tube boiler.”
• Lancashire boiler — typical shell diameter range Choose the correct nominal range for the cylindrical shell diameter of a Lancashire boiler used in industry.
• Boiler performance terms — identify the correct definition What is the term for the ratio of heat actually used in producing steam to the heat liberated in the furnace (based on fuel fired)?
• Willian's law (throttle-governed steam engine) — dependence of hourly steam consumption According to Willian's law, for a throttle-governed engine, the steam consumption per hour is proportional to which function of indicated power (I.P.)?
• Forced-circulation boilers — identify which use it Which of the following boilers operate with forced circulation of water (i.e., pumps circulate water through the evaporator)?
• Single-acting steam engine — identify admission and number of working strokes Which statement correctly describes a single-acting steam engine with respect to steam admission and working strokes per revolution of the crankshaft?
• Lancashire boiler — proportion of internal flue (furnace) tube diameter to shell diameter The internal furnace (flue) tubes in a Lancashire boiler have a diameter approximately equal to what fraction of the shell diameter?
• Compound steam engine — crank arrangement identification Name the compound engine in which the piston rods of the high-pressure and low-pressure cylinders are attached to two different cranks set at 90° to each other.
• Throttle-Governed Steam Engine — Interpolating Steam Rate vs. Power A throttle-governed steam engine develops 15 kW using 280 kg/h of steam and 35 kW using 520 kg/h of steam. Assuming linear variation of steam consumption with power over this range, estimate the steam consumption (kg/h) when the engine develops 20 kW.
• Boiler Classification by Circulation Mechanism When circulation of water within a boiler occurs due to convection currents naturally set up by heating (without the use of a pump), what is the boiler called?