Calculate the Lightship weight

Discussion in 'Hydrodynamics and Aerodynamics' started by Ghost Boy, Feb 20, 2020.

  1. Ghost Boy
    Joined: Oct 2019
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    Location: India

    Ghost Boy Junior Member

    Hello,
    I have lines plan. I wanna calculate lightship wight. Can anyone refer me any books or article or method? Thanks in advanced.
     
  2. TANSL
    Joined: Sep 2011
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    Location: Spain

    TANSL Senior Member

    Allow me please a previous question, do you know what lightship weight is?
     
  3. Ghost Boy
    Joined: Oct 2019
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    Location: India

    Ghost Boy Junior Member

    The lightweight is the displacement without cargo, fuel, lubricating oil, ballast water, fresh water and feed water, consumable stores and passengers and crew and their effects, but including liquids in piping.
     
  4. jehardiman
    Joined: Aug 2004
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    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    Does the lines plan state or show lightship draft and trim?
     
  5. TANSL
    Joined: Sep 2011
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    TANSL Senior Member

    Well, since you already know the most difficult, the rest is easy, add, multiply and divide. It is about putting a list with all the weights and their CoG and adding and multiplying.
    One of the important items is the weight of the hull and the superstructure. To calculate it, you should calculate the scantlings.
    Another important weight is that of the main and auxiliary engines. Calculate the necessary power and consult, in manufacturers' catalogs, the weights of the engines.
    You define all the equipment that the ship will carry and, likewise, check the suppliers' catalogs.
    You estimate the amount of pipes and wires and calculate weights and cog. And the same for all items.
    To the total you get, you add a 25% margin and you're done.
    I enclose a table that may help you.
     

    Attached Files:

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  6. Ghost Boy
    Joined: Oct 2019
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    Location: India

    Ghost Boy Junior Member

    Thank you sir for your file. Can you please suggest me any books or any article?
     

  7. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    You don't really need a book. Add the weight of everything, hull plating, framing, decks, piping, machinery, etc.
     
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