Steam Boilers and Engines Questions

• Boiler mountings — device on the steam chest to prevent overpressure damage Name the device fitted to the steam chest whose purpose is to prevent explosions by automatically releasing steam when internal pressure exceeds a safe limit.
• Boiler types — applicability of the high-steam & low-water safety valve The combined high-steam and low-water safety valve is not used on which of the following boilers?
• Boiler protection on dangerously low water level — identify the device Name the device used to automatically extinguish the furnace fire when water level in the boiler falls to an unsafe limit.
• Engine performance terms — power developed inside the cylinder What do we call the power actually generated by the working fluid on the piston within the engine cylinder (as obtained from the indicator diagram)?
• Boiler performance definitions — check the statement Is the following statement correct? “The ratio of heat actually used in producing the steam to the heat liberated in the furnace is known as equivalent evaporation from and at 100°C.”
• Cornish boiler — typical overall length range Select the most typical range for the length of a Cornish boiler used in industry.
• Feedwater heat-recovery placement — where is the economiser located? In a conventional boiler flue-gas path, the economiser is generally installed between which two components?
• Boiler performance terminology — choose the correct definition Is the following statement correct? “The amount of water evaporated from and at 100°C into dry saturated steam is called the evaporative capacity of a boiler.”
• Steam engine components — primary function of the piston Which statement best describes the main function of the piston in a reciprocating steam engine (with piston rod, crosshead, and slide valve)?
• Economiser benefit — is a 15–20% coal saving claim reasonable? Evaluate the statement: “There is about 15 to 20% saving of coal when an economiser is fitted in the boiler flue-gas path.”
• Condenser terminology — definition of vacuum State whether the following is correct: “The condenser vacuum is the difference between atmospheric pressure and the absolute pressure in the condenser.”
• Indicator diagram factor — relation between actual and theoretical mean effective pressures Given pa = actual mean effective pressure, pm = theoretical mean effective pressure, and K = diagram factor, which relation is correct?
• Surface condenser operation — do condensate and cooling water mix? Choose the correct statement regarding a surface condenser used with a steam engine or turbine.
• Boiler mountings — principal purpose of the steam stop valve What is the principal function of a boiler steam stop valve located at the outlet of the steam drum/shell?
• Condenser mixture of gases — computing total condenser pressure from partial pressures In a steam condenser, the partial pressures are: steam = 0.06 bar and air = 0.007 bar. What is the total condenser pressure?
• Steam plant components — identify the device A vessel into which exhaust steam from an engine or turbine is led and condensed to water for reuse is called a:
• Boiler feed line fitting — which valve is placed between the feed pump and the boiler shell? Identify the valve installed on the boiler inlet to control and prevent backflow of feedwater to the pump.
• Locomotive boiler draught production: In a locomotive-type multi-tubular fire-tube boiler, which device is primarily responsible for creating the draught (the pressure difference that draws air through the firebox and gases through the tubes)?
• Draught economics comparison: The ratio of the energy required to produce artificial draught (expressed as head or J per kg of flue gas) to the mechanical equivalent of the extra heat carried away per kg of flue gases when natural draught is used is termed the:
• Steam engine facts — choose the correct statement: Which of the following statements about steam engines is correct?