What You Should Know About The Limit VCG Curve

Discussion in 'Stability' started by bingli, Mar 15, 2022.

  1. bingli
    Joined: Jan 2020
    Posts: 25
    Likes: 5, Points: 3
    Location: China, Shanghai

    bingli Junior Member

    We all know that the lower the center of gravity, the more stable you stand.
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    The same is true for ships. The center of gravity is definitely an extremely important indicator for a huge ship to stand quietly at sea.
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    1, What is the limit VCG curve

    Smart ship engineers knew this for a long time, so they drew a limit VCG (Vertical Center of Gravity) curve from the beginning to help ship users efficiently and quickly evaluate the loading stability performance of the ship.

    This curve, considering all the relevant stability indicators of the ship, tells the ship user that in a certain draft state, as long as the height of the center of gravity does not exceed a certain amount, the ship is safe!

    2, Limit VCG curve, the magic weapon of stability assessment

    This curve is troublesome to calculate. It is necessary to comprehensively consider a series of stability indicators, iterative calculation for different VCG, and find the most extreme indicator condition!
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    The process is cumbersome, but the result is very simple:
    A limit VCG table
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    A limit VCG curve
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    This is what we need, the magic weapon for simple stability evaluation!

    3, Limit VCG Curve is easy to use

    It is very convenient to use, as shown below:

    Just calculate the VCG_attained for the current loading state, use the following graph to determine the maximum VCG_required, and you can know whether this loaded state is safe!
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    There is such a curve in the loading manual for each ship, have you found it? :)
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