hull deck joint

Do you mean for welding an aluminium superstructure?

Yes, the main deck is normally a structural element and forms part of the "girder" that determines the longitudinal strength of the hull.

The only deck I can think of that doesn't have a "hull-deck joint" is on some submarines. The deck is mounted so that compression of the hull at depth doesn't deform the deck and make the crew stumble and fall when they trip over bumps that weren't there earlier.

Steel deck joint

If a steel hull with Al. superstructure there is I believe a very expensive joining bar which allows the hull and superstructure to be welded together without the steel being in contact with the Aluminum, forget what it's called but a major piece of gear.

Before writing too much it might be worthwhile to spend some time with some IACS docs.

It is known as Triplate, Triclad and Datacouple

Corrosion doesn't know what length boat it is devouring.

Yes, the deck(s) are part of the vessel's "fabric." I strongly suggest you obtain IACS docs on the construction of steel vessels and read as much as you can about how they are surveyed. Little steel boats corrode and waste away in the same areas for pretty much the same reasons as the largest steel boats and they all flake and rot the same way..

If you plan to survey steel boats you really can't learn too much.

It's Detacouple in reference (I think) to the detonation created during the explosive welding process.

Hi,

OOPS - A Typo.

As far as I know they are all made and used in a similar fashion.

Detacouple: http://www.dynamicmaterials.com/data/brochures/1. SNAME paper 2-04.pdf

Triplate: http://www.triplate.com/?pagina=triplate_solution

Triclad: http://www.alumip.com/English/Product_content.asp?pid=252