General Subjects Homework Study Notes
1. Gate Valve in Pipeline
- Installation & Usage:
- A gate valve should be used in either the fully closed or fully open position.
- Installed with the stem facing down.
- Recommended for steam service only; not suitable for throttling or regulating liquid flow.
2. Centrifugal Pump Air Bound
- First Response Actions:
- A. Vent the casing.
- B. Close the discharge.
- C. Tighten the packing.
- D. Re-prime the pump.
3. Solenoid Operated Distillate Bypass Valve
- Location: Discharge line between a distilling plant and potable water tanks.
- Function: Prevent excessively warm distillate from entering potable tanks, avoiding salty overflow and contamination.
4. Salinity Indicating System
- Operating Principle: Measures:
- A. Electrical inductance of water.
- B. Electrical conductivity of water.
- C. Specific gravity of water.
- D. Hydrogen ion concentration of water.
5. Pyrometer Measurement
- Purpose: Used to measure:
- A. Grains of moisture per cubic foot of air.
- B. Salinity concentration of condensate.
- C. Stack temperature.
- D. Level of a fluid in a tank.
6. Maintenance of Compressed Air Receivers
- Required Procedures:
- A. Close watch on temperature.
- B. Constant cleaning to remove oil and dirt.
- C. Constant testing of the relief valves.
- D. Frequent draining of water.
7. Discharge vs. Suction Valves in Compressors
- Major Differences:
- Valves Operate Differently:
- A. One valve seats upwards; the other seats downwards.
- B. Discharge valves are made of thicker and heavier reed valves than suction valves.
- C. Suction valve springs have greater tension than discharge valve springs.
- D. Discharge valve springs exert greater tension than suction valve springs.
8. Typical Double Ram Electro-Hydraulic Steering Gear
- When Rudder Angle is Achieved:
- A. Ram relief valves bypass oil to stop rudder movement.
- B. Six-way valve shifts to neutral flow position.
- C. Steering pump electric motor is de-energized by the transfer switch.
- D. Follow-up gear takes the hydraulic pump off-stroke.
9. Starting Hydraulic Anchor Windlass
- First Action if Pressure Fails:
- A. Ensure the hydraulic reservoir is filled to proper level.
- B. Inspect the disc brake of the electric motor for proper operation.
- C. Check the electric motor for an open overload relay contact.
- D. Check for full voltage supply to the electric motor.
10. Orifice-Check Valve Function
- Purpose:
- A. Regulate fluid flow in either direction.
- B. Restrict movement of hydraulic fluid in one direction but allow free movement in the other direction.
- C. Allow free movement of hydraulic fluid in both directions.
- D. Allow only a restricted fluid flow in one direction.
11. Compliance with Federal Sewage Regulations
- Requirements:
- A. Hold all sewage onboard.
- B. Treat sewage in an approved system.
- C. Pump sewage ashore to an approved container.
- D. All of the above.
12. Shipboard Multicool Refrigeration System
- Key Statements:
- A. Liquid receiver collects and removes non-condensable gases.
- B. A thermostatic expansion valve controls refrigerated space temperature.
- C. Refrigerant temperature in an evaporator is directly related to refrigerant pressure.
- D. Dehydrators must always be used in a refrigeration system.
13. Flow of Refrigerant in Refrigeration System
- Component After Leaving Receiver:
- A. To evaporator coils.
- B. Liquid line strainer.
- C. Back pressure regulator.
- D. Condenser.
14. Maintaining Potable Water Quality
- Chemicals Commonly Used:
- A. Hydrochloric acid.
- B. Chlorine.
- C. Sulfuric acid.
- D. Zinc chromate.
15. Terms for Pipe Fittings
- Terms:
- A. Plug, bottom, and taper refer to:
- A. Pipe fittings.
- B. Measuring instruments.
- C. Machinist's hand tape.
- D. Drill press parts.
16. Roller vs. Ball Bearings
- Load Capacity:
- A. Installed with tighter clearance.
- B. Subject to less pitting and metal fatigue.
- C. Greater tolerance for high-speed applications.
17. Scale Formation Effects on Heat Exchangers
- Impact on Temperature:
- A. Water temperature outlet will decrease, and lube oil temperature will decrease.
- B. Water temperature outlet will decrease, and lube oil temperature may decrease.
- C. Water temperature outlet will increase, and lube oil temperature will decrease.
- D. Water temperature outlet will increase, and lube oil temperature will increase.
18. Erosive Tube Failure in Heat Exchangers
- Causes:
- A. Excessive cooling water velocity.
- B. Waterside fouling.
- C. High temperature.
- D. Poor heat transfer.
19. Lube Oil Filter Contaminants
- Remaining Contaminants post-Filtering:
- A. Water.
- B. Diesel oil.
- C. Acid.
- D. Sediment.
20. AC Generator Voltage Maintenance
- Maintaining Constant Output Voltage:
- A. Voltage regulator.
- B. Prime mover governor.
- C. Exciter generator.
- D. Reverse power relay.
21. Frequency Adjustment in Alternator
- Methods of Adjustment:
- A. Frequency meter.
- B. Voltage regulator.
- C. Governor control.
- D. Synchroscope switch.
22. Emergency Generator Power Supply Mechanism
- Device Used:
- A. Automatic bus transfer switch.
- B. Main lighting transformer.
- C. Power failure alarm bus.
- D. Main switchboard bus.
23. Shipboard Electrical System Control
- Device for Power Distribution:
- A. Bridge control panel.
- B. Disconnect links.
- C. Governor relay box.
- D. Main switchboard.
24. Routine Maintenance for Motor Controllers
- Maintenance Tasks:
- A. Inspect electrical wiring for corrosion/discoloration.
- B. Remove weather-exposed covers and drain water weekly.
- C. Remove motor covers and ventilate as weather permits.
- D. Check drum switch contact pressure every three months.
25. Shell and Tube Heat Exchanger Performance Issues
- Common Cause of Decreased Performance:
- A. Loose tube bundle baffle plates.
- B. Failure of the baffle plate.
- C. Rupture of the tube bundle.
- D. Fouling on sea water side.
26. Tools for Measuring Threads on Bolts
- Best Tool:
- A. Micrometer.
- B. Tap.
- C. Screw pitch gauge.
- D. Pair of outside calipers.
27. Steering Gear Operation Checks
- Action Recommendations:
- A. Check hydraulic oil levels hourly.
- B. Check rams for overheating.
- C. Check for excessive oil leakage from the rams.
- D. Drain water from telemotor cylinders each watch.
28. Micrometer Features
- Ratchet Stop Functionality:
- A. Click at each increment of measure.
- B. Prevent user from closing the tool with excessive force.
- C. Stop spindle from sliding out of the barrel.
- D. Eliminate ratchet movement.
29. Pipe Size in Hydraulic Systems
- Nominal Pipe Size Indication:
- A. Actual inside diameter.
- B. Actual outside diameter.
- C. Wall thickness.
- D. Size for threaded connections.
30. Pipe Coupling Definition
- Characteristics of a Coupling:
- A. Outside threads on one end and inside threads on the other end.
- B. Outside threads on both ends.
- C. A left-hand twist.
- D. Inside threads on both ends.
31. Three-Way Solenoid Valve Operation
- Operation Insights:
- A. Requires manual latch reset after tripping.
- B. Tripped if sea water feed temperature exceeds 180°F.
- C. Trips only under solenoid energization.
- D. Trips if distillate salinity is excessively low.
32. Swing Check Valve Functionality
- Used In Pipelines To:
- A. Maintain preset pressure.
- B. Closely regulate flow.
- C. Relieve excess pressure.
- D. Allow flow in one direction only.
33. Bilge Pump Troubleshooting
- Check Recommendations:
- A. Clogged suction strainer.
- B. Leaks in suction piping.
- C. Relief valve not seating properly.
- D. All of the above.
34. Pneumercator Function
- Purpose:
- A. Indicate fuel oil:
- A. Pressure.
- B. Level.
- C. Temperature.
- D. Flow.
35. Purpose of Swash Bulkheads
- Functions:
- A. Minimize listing effects.
- B. Restrict tank flooding.
- C. Separate cargoes in a common tank.
- D. Reduce liquid movement and surging within a tank.
36. Emergency Bilge Suction Requirement
- Required For:
- A. Ballast tanks.
- B. Sludge tanks.
- C. Machinery space bilges.
- D. Cargo hold bilges.
37. Overpacking Ball Bearings with Grease
- Effects:
- A. Bearings may overheat.
- B. Grease may flow out of seals.
- C. Early failure may result.
- D. All of the above.
38. Federal Pollution Prevention Regulations Enforcement
- Enforced By:
- A. Port Authority.
- B. U.S. Coast Guard.
- C. Corps of Engineers.
- D. State Pollution Board.
39. Discharge of Oil Under Pollution Regulations
- Qualifying Actions for Discharge:
- A. Leakage of oil through improperly blanked transfer hoses.
- B. Spilling oil on the main deck and it flows overboard.
- C. Pumping oil overboard through fixed piping.
- D. All of the above.
40. Fluctuating Demand on Device**
- Output Control Mechanisms:
- A. Complete shutdown until lower pressure limit is reached.
- B. Modulation of opening of a butterfly valve in the air intake.
- C. Change in control pressure to modulate discharge of compressed air.
- D. Proportional modulation of the compressor speed.
41. Device Identification from Illustration**
- Common Designation:
- A. Hydraulic steering gear pump.
- B. Multistage ballast pump.
- C. Rotary lobe type air compressor.
- D. Control air dehydrator.
42. Best Valve Type for Throttling Flow
- Ideal Valve Type:
- A. Gate valve.
- B. Globe valve.
- C. Check valve.
- D. Plug cock.
43. Characteristics of Pipe Thread Taps
- Qualities:
- A. Not hardened.
- B. Not fluted.
- C. Tapered.
- D. Straight.
44. Valve Types and Fluid Regulation Risk**
- Potentially Damaged Valves:
- A. Plug valve.
- B. Globe valve.
- C. Gate valve.
- D. Needle valve.
45. BTUs Required for Heating Water
- Heating Measurement:
- A. Adds:
- A. 16 BTUs.
- B. 144 BTUs.
- C. 180 BTUs.
- D. 970 BTUs.
46. Stop Check Valve Functionality**
- Operational Characteristics:
- A. Cannot be shut off remotely.
- B. Controls flow only in one direction.
- C. Can be opened manually for both directions.
- D. Contains both gate and check valve disks.
47. Jet Pumps Functionality**
- Device Definition:
- A. Mixed flow pumps.
- B. Jet pumps.
- C. Volute pumps.
- D. Centrifugal pumps.
48. Scale Accumulation Effects on Evaporators**
- Potential Outcomes:
- A. Immediate loss of vacuum.
- B. Increased distillate salinity.
- C. Immediate tube failure.
- D. Reduced evaporator capacity.
49. Distillation Plant Operation Statements**
- Correct Process Overview:
- A. Distillation involves boiling seawater to produce vapor which is condensed into fresh water.
- B. Evaporation is the second part of the distillation process where brine is removed.
- C. Brine results from condensed seawater vapor.
- D. Distillate is the product from evaporation of fresh water vapor.
50. Pressure Measurement Location for Duplex Pressure Probe**
- Most Likely Locations:
- A. Fuel service.
- B. Fuel oil strainer/pump discharge flange.
- C. Fuel oil heater.
- D. Fuel oil flow meter.
51. Unloading Air Compressor Methods**
- Methods to Unload:
- I. Holding the intake valve off its seat.
- II. Temporally relieving the intercooler to the atmosphere.
- A. Only I.
- B. Only II.
- C. Both I and II.
- D. Neither I or II.
52. Purpose of Separators Ahead of Air Line Lubricators**
- Main Function:
- A. Remove the heat of compression.
- B. Eliminate air supply pressure pulses.
- C. Remove moisture in the air supply.
- D. Minimize turbulence in the air supply.
53. Emergency Control of Electro-Hydraulic Steering Units**
- Control Method:
- A. Trick wheel.
- B. Rapson slide.
- C. Follow-up gear.
- D. Receiver unit.
54. Adding Hydraulic Fluid to Mooring Winch**
- Recommendation:
- A. Add fluid that matches the fluid color in the reservoir.
- B. Use turbine oil as a good substitute.
- C. Use any oil with the same viscosity.
- D. Check manufacturer's instructions.
55. Component for Separating Fine Dust from Hydraulic Fluid**
- Effective Device:
- A. Accumulator.
- B. Filter.
- C. Separator.
- D. Strainer.
56. Centrifuge Functionality for Fuel Oil Contaminant Removal**
- Contaminants Removed:
- A. Gasoline.
- B. Water.
- C. Lubricating oil.
- D. Sulfur compounds.
57. Marine Sanitation Devices per Coast Guard Regulations**
- Type IV Device:
- A. Holds sewage to be pumped offshore.
- B. Type I.
- C. Type II.
- D. Type III.
58. Small Refrigeration Appliance Components**
- Temperature Drop Expectation:
- A. Evaporator.
- B. Thermal expansion valve.
- C. Compressor.
- D. Receiver.
59. Refrigerant Admission Relation in Mechanical Systems**
- Directly Related To:
- A. Degree of opening of king solenoid valve.
- B. Degree of opening of water regulating valve.
- C. Degree of opening of box solenoid valve.
- D. Degree of opening of expansion valve.
60. Preventing Short-Cycling in Potable Water Pump**
- Recommendation:
- A. Hydropneumatic tank at operating pressure fully filled with air.
- B. Hydro pneumatic tank filled with water.
- C. Charge of air at 20psi (137 kPa) above system pressure with tank one-quarter full.
- D. Charge of air at system pressure when the tank is half full.
61. Rotating Large Pipes**
- Recommended Tool:
- A. Chain pipe wrench.
- B. Monkey wrench.
- C. Basin wrench.
- D. Strong back.
62. Protecting Heat Exchanger Tubes from Erosion**
- Protection Methods:
- A. Metallic packing on the inlet end.
- B. Fiber bushings in ferrules.
- C. Zinc pencils on waterside.
- D. Plastic tube end protectors.
63. Pressure Measurement Terms**
- Gauge Pressure Definition:
- A. Pressure at a point compared to vacuum.
- B. Internal pressure.
- C. Absolute pressure.
- D. External pressure.
64. Wearing Rings in Centrifugal Pumps**
- Main Function:
- A. Maintain radial alignment of the pump impeller and casing.
- B. Absorb all impeller shaft end thrust.
- C. Prevent water leakage to atmosphere.
- D. Economically replace worn parts during maintenance.
65. Verifying Pneumercator Level Readings**
- Initial Reading Verification:
- A. Repeat the process for consistent readings.
- B. Sounding the tank with tape coated with fuel