competence 9.1

58問 • 1年前

問題一覧

1. In a closed cooling system for a turbocharged four stroke diesel engine, fluctuating water pressure can be caused by? Eh

•an incorrectly set cooling system pressure control

2. To properly use a tube expander, the expander should be placed in the tube to be rolled so that the

•rollers bear on the portion of the tube which is in the tube shee

3. During the operation of a lube oil centrfuge, a thin emulsion interface occurs between the lube oil and seal. The position of this interface is determined by the

•inside diameter of the ring dam

4. Which characteristic or condition will have the greatest effect on increasing a hydraulic oilas viscosity?

•pressure

5. Fusible link fire dampers are operated by.

•the heat of a fire melting the link

6. The measure gap between the face of the burner atomizer tip nut and the diffuser plate, is determined by the setting of the

•distance piece

7. Which of the following precautions should be observed concerning the introduction of a fire resistant fluid into a hydraulic system?

•Deterioration of paints, seals, metals, and electrical insulation may occur

8. If the hydraulic governor has been drained and refilled with fresh oil, the engine should be operated until it reaches normal temperature, then the air should be purged by.

•compensating needle valve adjusted by stability,

9. Which pressure in an operating hydraulic system is developed,

•by resistance to the fluid flow through the system

10. Low scavenging pressure delivered to the engine can cause ?

•high exhaust temperature in all cylinder

11. When the pressure on a compound gage is released, the gage pointer is returned to zero psig by action of the

•bourdon tube

12. Which of the following material has high tensile strength and corrosion resistance and has been used to replace steel metal in both flat plate form and in matched-metal die processes where parts are molded in the preformed shape?

•Titanium

13. For any piston ring to operate smoothly without scuffing, the ring must be ?

•lubricated properly during engine operation

14. Diesel engine starting difficulties due to cold intake air temperatures, can be overcome by using alan?.

•jacket water heater

15. Acetylene should never be used at pressure in excess of 15 psig because the ?

•slightest backfire could cause an explosion

16. The insertion of shims between the foot of a marine type connecting rod and a bearing box would result in.

•increased compression ratio

17. Leakage of hydraulic fluid from around the shaft of a hydraulic motor may be caused by.

•Worn shaft seals

18. When conducting a routine hydrostatic test on a water-tube boiler, you should,

•have gags installed on all safety valve

19. What do you call the portion of a hydraulic hose that determines its overall strength?

•braided inner layers

20. Why is a hydraulic linear actuator fitted with a cushioning device?

• To slow the action of the piston preventing shock and damage due to hammering effects.

21. The ventilation system aboardships has fire dampers restrained by fusible links that will ?

•need replacement if the damper remains closed

22. Which of the following centrifugal pump components converts the liquid kinetic energy of velocity to the potential energy of pressure?

•Volute

23. What is the used of jacking gear on main propulsion turbines?

•provide complete gear tooth inspection

24. What is the possible cause why a lube oil pump fails to build up discharge pressure?

•Suction valve is closed

25. What is caused by restriction occurring in the small orifices of pneumatic control system components?

•Moisture in the compressed air supply

26. Which of the following problems occurring in a hydraulic system can be caused by using an oil having a viscosity lower than specified?

• Increased wear of moving parts.

27. A work piece has been mounted between centers and a test cut machined at each end to check alignment of the lathe centers. If the test cut on the tailstock end is deeper than the test cut on the headstock end, the tailstock must be moved?

•away from you to correct alignment

28. Which of the following is the proper maintenance for a lube oil pump?

•Inspect the telltale holes for leakage

29. Which of the following is true concerning the hose threads on compressed gas oxy-acetylene regulators and torches ?

•The torch oxygen inlet hose thread connection is "right"handed

30. Modern trends show that the full flow filters used in multi-operation hydraulic systems would most likely be located ?

•in the reservoir return line

31. In order to install piping easier and to facilitate and disconnect the pump for servicing, which of the following fittings should be used?

•Quick disconnect coupling

32. Which of the factors listed governs the intensity of heat required for any given welding job?

•The type of metal being joined and the welding process used

33. Which internal combustion engine starting system uses a vane type fluid motor?

•Compressed air

34. In certain cases, a cylinder liner can be refinished rather than replaced. When properly honed, the?

•liner surface should have a crosshatch pattern

35. What will be the effect of obstructed suction passages in the casing or pintle of a radial piston hydraulic pump?

•Pumped fluid volume to decrease

36. If the hydraulic governor has been drained and refilled with fresh oil, the engine should be operated until it reaches normal temperature, then the air should be purged by?

•compensating needle valve adjusted for stability

37. The purpose of the diffuser in a boiler burner assembly is to

•shield the flame from the incoming air blast while allowing some mixing of fuel and air

38. What would you do after adding grease to a ball bearing with a hand held grease gun?

•Run the machine with the bearing housing drain plug open for a short while

39. In the case of a variable speed centrifugal pump?

•capacity varies directly as the speed

40. What can cause dirt in a fuel oil system to the diesel engine?

•Injector damage

41. Why should a return lines in a non-pressurized hydraulic system reservoir enter the tank well below the fluid surface level?

• Prevent foaming

42. How can the leak in a hydraulic system in a hatch cover be remedied?

•Shut down the power unit and use two wrenches to avoid damaging the tube when tightening.

43. Which ring dam arrangement should be used for centrifugal purification?

•The largest inside diameter ring without loss of oil.

44. The large number of mechanical and pulsating vibrations developed in a diesel engine may damage an attached?

•gas driven turbocharger because it has a wide speed range and high temperature materials that are subject to resonant vibration

45. What is a one common cause of cylinder liner wear?

•burning heavy fuel oil with significant amount of sulphur

46. On a large low-speed main propulsion diesel engine, lower main bearing wear is usually measure by using alan

•bridge gauge

47. Abnormal crankpin bearing and piston skirt surface wear indicate a__?.

•incorrect connecting rod alignment

48. Which of the listed interlocks stops the valve in the remote operating valve line of air starting system from opening?

•Turning Gear

49. While your vessel is steaming with one boiler, the automatic combustion control system sensing line for the idle boiler is accidentally opened. How will this effect the steaming boiler?

•The steam pressure rise

50. The ignition quality of a fuel oil is an important operational consideration because it?

•affects the starting ability of a cold engine

51. What will happen if a diesel engine is running in about to dry fuel oil day tank ?

•air in the fuel system

52. With respect to diesel fuel, the ease with which a cold engine will start is dependent upon the?

•ignition quality of the fuel

53. Which of the following is the proper maintenance for a lube oil pump?

•inspect the telltail holes for leaakage,

54. If the intercooler of a low-pressure air compressor becomes fouled either internally or externally, what will happen?

•volumetric efficiency will be decreased

55. Thermocouple pyrometers are sued on large, main propulsion diesel engines to indicate the temperature of the ?

•exhaust gases at various locations

56. Which of the following operating conditions can occur when shims are removed from the joint between the foot of a marine type diesel engine connecting rod and the bearing box?

•Decreased compression ratio

57. Increased internal leakage, in addition to poor hydraulic system response, and inadequate lubrication, is the result of ?

• low hydraulic oil viscosity.

58. Thermocouple pyrometers are used on large, main propulsion diesel engines to indicate the temperature of the

•excaust gases at various locations

competence 4.1

ERNO ENRIQUE JOMENTO · 50問 · 1年前

competence 4.1