Fabrication standard for penetration

Dear Members

after years working and designing composites boats. recently I am working for aluminium boat yard , have been digging and eating rules of several class BV and DNV but so far i cant find standard scantling of penetration for hull, bulkheads and decks. only normative quotes like " shall be strengthened" or something like " having adequate support". What i looking for is some detailed drawing and scantling like this:



is there any source for this matter, i tried to find on IACS but there is too many files to explore and hopefully someone could bring some light. Thank you.

 

I got it after simply gooling up with these keyword : piping standard penetration

https://www.google.co.id/url?sa=t&r...=YHcqsHjlQmyiY3gpoyfyBA&bvm=bv.92291466,d.c2E

 

normally those who built and sold the plates must know the data Brinell of their material

 

Basically the penetration of the shell plate must have a localised increase of 1.5 times the surrounding plate thickness. In addition the foundations/seating must be stiff in a minimum of 2 axis to prevent movement and vibration issues.

That's it.

 

What exactly do you mean by penetration?
Term normally applies weld penetration

 

Tubes, for example, penetrating the hull (see figure in post # 1)

 

gents, Thank you so much for reply. Ad Hoc, thanks for valuable rule of thumb figures. hope this post will be usable for others.

 

OKEY DOKEY

 

normally on alluminium boat I turn a ring, seal weld outside to shell and light bead all around inside
then screw a ss valve on, throwing away the flange of the 3 piece valve so the teflon seal sits on the ring, making the seal
then I isolate screws with shrink tube and poly something or other washers keeping the inboard flange
thickness of ring, is usually 2 to 2.5 dia of screw, so 10mm hex head need 25 plate for Lloyds if I remember correctly
in reality 20 pl is ok
sorry abt vague comment re penetrations, was half asleep and last build was 16 yrs back
sorry too abt the very rough scetchup

 

Thanks Oleboi... very inforamative input.

 

prob worth noting, that you cannot use the thread of the bolts that hold these 3 piece valves to tap the pad flange, cos they are not a recognised thread, but some random thread used by the valve maker
I prefer UNC
But the valves are trouble free and so far 30 years service on some of my builds