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1. A bourdon-tube type steam pressure gauge is fitted with a siphon loop to prevent damage from _______.


2. Oil emulsification in engine lubricating oils will tend to ________.


3. The oil trap should be installed on refrigeration system _______.


4. To add oil to an R-22 reciprocating compressor that has been shut down for this purpose, the oil _______.


5. Which is not used to lubricate a Freon-12 compressor?


6. Which is NOT true about refrigerant oils?


7. A refrigerant oil tested to have a low neutralization number indicates _______.


8. The “fire point” of a refrigerant oil means the _______.


9. The dielectric property of oil refers to the _______.


10. Raising head pressure raises discharge temperature and _______.


11. It is desired to operate an air compressor with a 30.54 cm flywheel at a speed of 510 RPM. If a motor runs at 1750 RPM, what size of motor pulley should be used?


12. An air compressor is equipped with an intercooler and an aftercooler to ______ .


13. To obtain maximum efficiency, two stage air compressors are usually _______ .


14. If the intercooler of a low pressure air compressor becomes fouled either internally or externally, the ________ .


15. The heat of compression is partially removed from the compressed air by ______


16. Why do we drain the condensate from the intercooler and aftercoolers of an air compressor?


17. For any given volume of compressed air produced by a multistage air compressor, interstage cooling will ________ .


18. Which of the following statements describes the function of an air compressor intake filter?


19. Moistures and impurities can be removed from the pneumatic systems by using ______ .


20. What is the primary function of unloading system on an air compressor?


21. Air compressor cylinder unloaders enable the compressor to _______ .


22. In addition to pressure gauge and relief valve, an air receiver should be fitted with a ________ .


23. If the drive belts on an air compressor were squealing, you should fix them by ________ .


24. If one drive belt on an air compressor is found to be worn you should _______ .


25. Which is not used to lubricate a Freon-12 compressor?


26. The main difference between ferrous metals from nonferrous metals is _______.


27. What is your observation and conclusion regarding the effect of carbon content when comparing the tensile strength, ductility, and hardness of low-, medium-, and high-carbon steel?


28. What is the main purpose of alloy?


29. Which is true about the uses of gray cast iron?


30. What is the basic alloy composition of brass?


31. A metal used in piping on board ships that is more durable than copper pipes and is also used in cooling water installations, sanitary installations, oil coolers, and heat exchangers, heat coils etc is called _______.


32. How is annealing process carried out?


33. How is hardening process carried out?


34. Why do we apply tempering process on metals?


35. Which statement is true regarding the purpose/use of the alloying element chromium?


36. Why are metallurgical tests carried out upon materials?


37. A method of detecting surface defects (e.g., cracks) by the use of microscope or hand lens is called _______.


38. A type of penetrant testing which is wiped or sprayed over the metal surface which is then washed, dried and inspected under ultraviolet light is called _______.


39. What is the main reason for using glass fiber as a filler material in polymers?


40. Which one “N” stands for? IHP=PLAN/(33000): ?


41. In a trunk piston engines, what is the primary cause of cylinder liner bore polishing?


42. Where is the duplex pressure gauge located?


43. The fuel oil strainer disks, spacers and scraper blades should be made of __________material to minimize corrosion.


44. Which of the following elements in the fuel can make the lubricants more difficult in a diesel engine?


45. It is a measure of fluid’s resistance to flow under gravity at a specific temperature (usually 40 deg. C to 100 deg. C) _____ .


46. What color is the smoke of burning sulphur if ammonia is present?


47. A material, valve and piping in ammonia system is composed of __________.


48. A finished product of fuels leaving the refinery have a sodium level below _____________.


49. It’s a measure of ignition quality of a diesel fuel as determined in a standard single cylinder engine _____ .


50. The major contaminants in fuels are ________.


51. It is a measure of the acidity or alkalinity of an oil _______.


52. What is the function of fins on the tubes of a fin type fuel oil heater?


53. What is probable cause if there is a flame failure in an automatically fired auxiliary boiler?


54. It is the lowest temperature at which the fluid will flow when cooled under prescribed condition ________ .


55. What do you call the temperature at which an indication of wax crystals appears when lubricant or distillate fuel is cold?


56. In diesel engineering practice, the term used to express the ignition quality of a particular fuel is ________ .


57. Which of the following represents the significance of the fuel oil cetane number?


58. Fuel oil having a low cetane rating could result in _______ .


59. In order for microbiological growths to thrive in fuel tank it is necessary for ________ .


60. Fuels are produced in a refinery are generally sterile, however, contamination can occur as fuels are ________ .


61. The microbiological growths that affect fuel supplies can easily be transported from one location to another by _______ .


62. It is defined as the resistance of fuel oil to flow ________ .


63. It refers to the sediment –forming tendency of a manufactured fuel when mixed with another fuel _______ .


64. What is meant by Calorific Value of a fuel oil?


65. What is the major potential safety hazard associated with petroleum products?


66. What are the main contaminants in fuels?


67. In thermal cracking of crude oil, what is the main aim of the conversion process?


68. What is the reason why onboard fuel oil settling tanks are installed ship?


69. What is a harmful effect of sulfur in a fuel?


70. In running diesel engine emitting a black smoke is cause by _________.


71. In a single-acting diesel engine which one cylinder liner is the most difficult to lubricate?


72. A combustion knock will probably happen when using a fuel with _________.


73. An operating condition referred to black smoke?


74. Between the mating parts of a hydraulic actuator at high pressure an O-ring has a tendency to extrude into the clearance space In order to prevent a _________ is installed.


75. In what component a O-ring seal be satisfactorily use in providing a seal in hydraulic?


76. Which of the following hydraulic system is the installation of oil cooler is necessary?


77. In what stage where the changes in the property of a body cease?


78. The combination of two metals to produce a joint that is as strong as the metal itself is called ________.


79. All energy received as heat by a heat engine cannot be converted into mechanical work is a demonstration of _______.


80. The form of energy associated with the random motion of large numbers of molecule is known as _______.


81. The velocity of a fluid particle at the center of the pipe section is _______.


82. Which gas is liberated when the lead-acid battery is being charged?


83. When charging a compression refrigeration system with vapor, the charging is done to the _______.


84. A single pass condenser is known as _______.


85. A fore and aft reference line at the upper surface of the flat plate keel at the centerline on flush shell plated vessels or the thickness of the garboard strake above that level for ships having lapse am shell plating is called _______.


86. What precautionary measure/s is/are to be observed when starting on a R-22 compressor?


87. The property of a liquid whereby its own molecules are attracted to each other is known as _______.


88. A comfortable room temperature is 72 deg. F. Which is the equivalent of this temperature in degrees Celsius?


89. When suction pressure is decreased, the horsepower per ton of refrigeration will _______.


90. As suction pressure drops in a Freon-22 system , compressor capacity will _______.


91. If tonnage increased as the suction pressure is increased, horsepower will _______.


92. The temperature on a wet-bulb thermometer equals the dry-bulb temperature when _______.


93. If compression ratio and horsepower increases, tonnage _______.


94. What causes oil to foam in the compressor crankcase?


95. Which refrigerant is the least flammable and the most toxic?


96. If an R-12 system has too much refrigerant, it will result to _______.


97. The refrigerant in the evaporator absorbs heat from air or brine because liquid refrigerant entering it ________.


98. In a Freon-12 compressor with a splash scoop lubrication system ,what causes the oil to foam?


99. Freon-12 is is similar to methyl chloride because _______.


100. A most desirable quality of Freon refrigerant is _______.


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