bulb bar connect to flat bar alignment

Discussion in 'Metal Boat Building' started by Brian.Lin, Apr 26, 2016.

  1. Brian.Lin
    Joined: Aug 2006
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    Brian.Lin Junior Member

    Dear sir,

    is there any document or data to talk about the alignment between bulb bar and flat bar.
    attached have two kind of alignment. which one is better.

    Attached Files:

    • 01.jpg
      File size:
      28.1 KB
  2. Ad Hoc
    Joined: Oct 2008
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    Location: Japan

    Ad Hoc Naval Architect

    In general, you would not do as detail A. Because you have introduced a bending moment between the bkt and the bulb bar owing to the eccentric load path. Detail B is the more common method.

    The only acceptable way for doing detail A would be to ensure that the centreline of the web of the bkt does not extend beyond the edge of the inner web of the bulb. As noted here:

    Offset Bkt detail-LR.jpg

    Since if you do as detail A, the shear path is eccentric and thus creates a bending moment rather than just a shear path. But in reality the welder will not want to measure small mm's here and there to ensure the alignment is 100% correct and not exceed as detail A shows. It is much quicker and easier to align with the end, as detail B too.
  3. Alexanov
    Joined: Feb 2003
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    Location: Norway Sola

    Alexanov Senior Member

    Agree. Detail b more practical.
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