Aux 1 Unit 3 Q1 – Answer

Valve Selection for Different Applications:

(i) Main Engine Lubricating Oil Pump Delivery:

  • Valve Type: Globe Valve
  • Reasons:
    • Regulation and Isolation: A globe valve allows for fine control of lubricating oil flow by adjusting the opening. It also provides positive shut-off for isolating the pump during maintenance.
    • Pressure Handling: Globe valves are suitable for handling the moderate pressure requirements of lubricating oil systems.
    • Direction Change: The internal design allows for changes in flow direction without significantly impacting performance, which might be relevant in some lubricating oil system designs.

(ii) Fuel Service Tank Outlet:

  • Valve Type: Remotely Operated Quick Closing Valve
  • Reasons:
    • Emergency Shut-Off: This valve prioritizes safety in case of fire or leaks. Remote operation allows shutting off fuel flow from a safe location.
    • Leak Prevention: A quick-closing mechanism minimizes the amount of fuel released in case of a leak or line rupture.
    • Material Compatibility: The valve material should be compatible with the specific fuel type to avoid corrosion or degradation.

(iii) Ballast Tank:

  • Valve Type: Butterfly Valve
  • Reasons:
    • Easy Operation: Butterfly valves offer easy opening and closing with a quarter-turn operation, ideal for frequent ballast tank operations.
    • Low Pressure Drop: The design minimizes resistance to flow, which is important for efficient ballast water transfer.
    • Cost-Effective: Butterfly valves are generally less expensive compared to other options for this application.

(b) Information Required for Ordering a Replacement Valve:

To correctly order a replacement valve, you’ll need the following information:

  1. Valve Type: Specify the type (e.g., globe valve, butterfly valve, quick-closing valve).
  2. Nominal Pipe Size (NPS): This indicates the diameter of the pipe the valve is designed for.
  3. Pressure Rating: Specify the maximum pressure the valve can handle.
  4. Material: Indicate the valve body and internal component materials (e.g., cast iron, stainless steel).
  5. Flange Standard: Specify the flange connection type (e.g., ANSI, DIN) for proper fitment with existing piping.
  6. Connection Type: Indicate if threaded, flanged, or other connection type is required.
  7. Manufacturer (Optional): If you prefer a specific brand, include the manufacturer’s name.

Application Details (Optional): Providing details about the intended use (e.g., fuel oil, lubricating oil, seawater) might be helpful for the supplier to recommend suitable options.