e. Steam Power Plant - Pe - Exam

STEAM POWER PLANRT – PRACTICE ELEMENT 1. Which of the following statement is true for a vapor dome drawn on a T-S diagram? a. The bell-shaped curve indicates the saturation points for a constant pressure. b. The region under the bell-shaped curve indicates superheating. c. The bell-shaped curve indicates the saturation points for various pressures. d. The left side of the bell-shaped curve indicates saturated vapor. 2. The primary effect of reheating is to: a. Increase the efficiency b. Decrease the pump work c. Decrease the heat requirement d. Decrease or eliminate moisture condensation in the turbine. 3. The contamination of various amounts of water and impurities out of the boiler. a. Priming b. Steam purity c. Spray d. Carryover 4. The liquid contamination in the steam, expressed in percentage, by weight, of the mixture. a. Steam quality b. Steam quantity c. Liquid quality d. Wet quality 5. The solids impurity in the steam, expressed in parts per million (ppm) of impurity. a. Steam spray b. Steam purity c. Steam quantity d. Steam baffles 6. Type of carryover that will occur under conditions of high water level or severe surging in the boiler drum. a. Priming carryover b. Spray carryover c. Foamover d. Steam sampling 7. A device used to determine the quality of steam. a. Throttling calorimeter b. Steam valve c. Steam vent d. Steam nozzles

8. First step in purification of steam and necessary in water tube boilers. a. Primary separation b. Steam washing c. Steam cleaning d. Steam drying 9. Consist of a separating and throttling calorimeter, of high and low range. a. Electric calorimeter b. Universal calorimeter c. Throttling calorimeter d. Steam calorimeter 10. A process of removing small amounts of moisture from a relatively large volume of steam, is essentially a filtration process. a. Heating b. Ventilating c. Drying d. Washing 11. When a heater is used to increase the temperature between expansion stages to approximate isothermal expansion. a. Reheater b. Heater c. After heater d. Intercooler 12. Any boiler which does exceed any of the following: 405 mm inside diameter and 1065 mm overall length of outside to outside heads at center. a. Portable boiler b. Miniature boiler c. Locomotive d. Power boiler 13. A closed vessel intended for use in heating water or for application of heat to generate steam or other vapor to be used externally to itself. a. Boiler b. Boiler or steam generator c. Steam generator d. None of these 14. A vessel in which pressure is obtained from an external sources, or from an indirect application of heat. a. Unfired pressure vessel b. Pressure vessel c. Power boiler d. Low pressure boiler 1

15. Any boiler or unfired pressure vessel constructed, installed, placed in operation but subject to annual inspection. a. Existing installations b. New boilers c. Hot water boilers d. Reinstalled boilers 16. A boiler in which that has been inspected and declared unsafe to operate or disqualified stamped and marked indication its rejection. a. Second hand b. Reinstalled c. Condemned d. Unfired 17. No part of the steam generator should be closer than ___ meter from any walls of the building. a. One b. Three c. Two d. 4 18. Steam generators should be mounted over a suitable foundations or concrete pad of not less than ___ thick and with sufficient base area. a. 150 mm b. 255 mm c. 195 mm d. 305 mm 19. When new boilers are installed in either existing or new buildings, a minimum height of at least ___ shall be provided between the top of the boiler proper and ceiling. a. 2130 mm b. 900 mm c. 1560 mm d. 746 mm 20. When feeding hot water, feed-pump should at least be ____ below hot well to prevent vapor lock. a. 550 mm b. 1220 mm c. 990 mm d. 3050 mm 21. A steel catwalk or platform at least ___ wide and provided with standard handrails and toeboard on either side shall be installed across the tops of adjacent boilers. a. 255 mm b. 455 mm c. 355 mm d. 555 mm

22. For power boilers, when the tensile strength of steel is not known, it shall be taken as ___ N/mm2 and 310 N/mm2 for wrought iron. a. 379 b. 450 c. 398 d. 521 23. For power boilers, the resistance to crushing of mild steel shall be taken at ___ N/mm2 of cross sectional area. a. 655 b. 855 c. 755 d. 955 24. The lowest factor of safety permissible on existing installation shall be ____ excepting for horizontal return tubular boilers having continuous lap seams more than 3650 mm in length where the factor of safety shall be. a. 4.5, 9 b. 9, 4 c. 5.5, 8 d. 8, 5 25. Reinstalled or secondhand boilers shall have a minimum factor of safety of ____ when the longitudinal seams are of lap riveted construction, and a minimum factor of safety of ____ when the longitudinal seams are of butt and double strap construction. a. 6, 5 b. 5, 6 c. 4, 6 d. 6, 4 26. The age limit of a horizontal return, flue or cylinder boiler having a longitudinal lap joint and operating at a pressure in excess of 0.345 MPa shall be ___. a. 10 yrs b. 20 yrs c. 15 yrs d. 30 yrs 27. For power plants, each boiler shall have at least one safety valve and if it has more than 46.5 sq. m. of heating surface or the generating capacity exceeds 910 kg/hr, it shall have ___ safety valves. a. One b. Two c. Two or more d. Three or five 2

28. For miniature boilers, the lowest permissible water level shall be at a point ___ of the height of the shell, except where the boiler is equipped with internal furnace. a. ½ b. 1/3 c. ¼ d. 2/5 29. Where ground water or surface water is used for feedwater, water hardness of 0-10 ppm (parts per million) and alkalinity of ___ be considered. a. ph 10 to pH 11 b. pH 9 to pH 10 c. pH 6 to pH 10 d. pH 8 to pH 10 30. A closed vessel which steam or other vapor is generated at a pressure of more than 1.055 kg/cm2 gage by the direct application of heat. a. Power boiler b. Boiler c. Fusion boiler d. External boiler 31. The heating surface are of miniature boiler is 1.85 m2 and the maximum allowable working pressure is ____ kg/cm2. a. 7.03 b. 9.85 c. 8.05 d. 14.7 32. Low pressure heating boiler is a boiler operated at pressure not exceeding 1.055 kg/cm2 gage steam or water temperature not exceeding __ deg C. a. 100 b. 121 c. 111 d. 145 33. A boiler of which both the location and ownership have been changed after primary use. a. Internal boiler b. Second hand boiler c. Surplus boiler d. External boiler 34. A boiler removed from its original setting and re-erected at the same location or erected at a location without change of ownership/ a. PSME Boiler b. Reinstalled boiler c. Fusion boiler

d. Unknown boiler 35. Each miniature boiler, shall be equipped with a sealed, spring-loaded, pop type safety valve not less than ___ pipe size, connected directly to the boiler. a. 10.2 mm b. 15.6 mm c. 12.7 mm d. 25.4 mm 36. Each miniature boiler shall be equipped with ____ for determination of water level. a. Pressure gage b. Safety valve c. Water gage glass d. Fusible plug 37. Each miniature boiler shall be equipped with a steam gage having a dial range not less than __ times and not more than twice the maximum allowable working pressure. a. One b. 3 c. 1.5 d. 4 38. The maximum allowable working pressure of a non-code steel or wrought iron heating boiler of welded construction shall not exceed ___. a. 2 MPa b. 1 atm c. 2 gage pressure d. 1 bar 39. A large pipe or drum into which each group of boilers is connected. a. Muffler b. Header c. Manifold d. Expansion loop 40. If the pressure is disregarded in the various components of a steam power plant, the pressure drop in the pump is ______ to the pressure drop in the turbine. a. Proportional b. Constant c. Inversely proportional d. Unity 41. A feedwater preheating device which utilizes the heat of the flue gases. a. Feedwater heater b. Heater valve c. Economizer d. Heater coils 3

42. Type of boiler in which the water is outside the tubes while the hot gases pass inside the tubes. a. Water tube b. Tubulous c. Horizontal d. Fire-tube 43. What process is employed when the turbine in steam power plants experience excessive moisture? a. Subcooling b. Freezing c. Supercooling d. Reheating 44. If H is the work output of a heat engine and Q is the total heat input of an engine, then determine its thermal efficiency. a. H/Q b. Q/H c. 1 – H/Q d. Q/H – 1 45. If Wb is shaft work of an engine and Wi is the indicated work of an engine, then which of the following relationship is correct if mechanical friction is present in the engine? a. Wb is less than Wi b. Wb is greater than Wi c. Wb is equal to Wi d. Wb is proportional to Wi 46. What is the pressure present inside the casing of an impulse turbine? a. Vacuum b. Atmospheric pressure c. Above atmospheric d. Zero 47. For steam power plant, decreasing the operating pressure of the boiler will: a. Increase thermal efficiency b. Decrease thermal efficiency c. Bring thermal efficiency d. Make thermal efficiency 48. A device used to convert thermal energy into kinetic energy and also used to direct the mass flow to its specified direction by means of a variable duct area. a. Throttling valve b. Nozzle c. Diffuser d. Header 49. In the Rankine cycle, an engineer wants to increase the efficiency of the boiler by reducing

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the moisture in the final stage of the turbine. What will the engineer do? a. Reheat the steam b. Increase the back pressure c. Replace the condenser d. Decrease the back pressure Servomotor controls a. Moving vanes b. Moving and guide vanes c. Guide vanes d. None of these In order to increase the back pressure of a boiler. a. Increase the boiler pressure b. Close the atmospheric line c. Open the back pressure valve d. Close the back pressure valve The ratio of net work out divided by the heat input. a. Power factor b. Thermal efficiency c. Brake power efficiency d. Power ratio The ratio of the actual to ideal (isentropic) energies extracted from the flowing gas. a. Nozzle efficiency b. Pipe efficiency c. Work ratio d. Pressure ratio -

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