[PSUBS-MAILIST] hemi heads

[Sean T. Stevenson via Personal_Submersibles]

I'd be interested in having a look at those drawings.  The idea with a
conical bearing face on a hatch, if you are not trying to establish a
metal-to-metal seal, is to provide a load path through the hatch itself
to carry the shell stress that would otherwise require heavy
reinforcement around the hole.  Thus, the "ideal" hatch would be the
same thickness and curvature as the shell it is replacing, aligned to it
so the load transfers straight through, with a flange on both the hatch
and shell parts to create a substantial bearing face.  The conical angle
in that case would be set by the hatch diameter, as the ideal interface
angle would be perpendicular to the shell at every point.  I suspect
that in practice, the cone is exaggerated beyond that, because we're
talking about very small angles on larger spheres - on a PSub, perhaps
it is more important.  The other advantage is of course the self-centering.

Sean


On 2015-11-07 16:26, hank pronk via Personal_Submersibles wrote:
> Dr Nuytten thinks he has detail drawings that he is willing to share
> with me, if he can not find them, he has given me permission to measure
> one of his Pisces in the bone yard.   I may have a look for myself even
> with drawings, just because I am a visual guy- if I see it I can make
> it.   Besides, how fun is a day at the Nuytco bone yard :-)
> Hank