[PSUBS-MAILIST] hemi heads

Sat Nov 7 17:11:02 EST 2015

I think that integral is always stronger than fastened, and in any case you need to take reinforcement requirements into account. Every opening you cut in the hull shell must be reinforced with additional material to retain the load carrying capacity. The absolute best way to do that is with a monolithic casting, but short of that, cutting a larger opening and welding in a thicker shell pad, tapered back to the main shell, and welded to the window seat with geometry which minimizes stress concentrations is the way to go. If you don't reinforce, you need to derate the entire shell, and are then carrying much more weight than necessary.

That said, having shells which open for access / maintenance is not a bad idea, but the flanges or reinforcing rings used for this purpose need to be substantial. 

Sean

On November 7, 2015 12:54:35 PM MST, hank pronk via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>I would love to build it so it was all bolted together, I could see
>making bolt on window ports and hatch land.  What do you think about
>that?  What do you think about having the hemi heads machined with a
>flat face instead of a bevel.  Hmmm that would be amazing!Hank 
>
>
>On Saturday, November 7, 2015 10:17 AM, Sean T. Stevenson via
>Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>   
>
>For a pressure hull?  100% radiographic examination (x-ray) on all butt
>joints, 100% ultrasonic examination on all joints other than butt
>joints, not less than 72 hours after welding is complete.Surface
>inspection methods (liquid penetrant, magnetic particle or eddy
>current) at your discretion.Criteria can be found in the ABS Guide for
>Nondestructive Inspection of Hull Welds (NDI Guide).Sean
>
>
>On November 7, 2015 8:57:58 AM MST, hank pronk via
>Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>Sean,I am looking for a company in Calgary to do NDT of welds on my
>deep diver and have discovered there are many different tests
> available.  What tests should I be looking for?Hank 
>
>
>On Friday, November 6, 2015 6:51 PM, Sean T. Steve! nson
>viaPersonal_Submersibles <personal_submersibles at psubs.org> wrote:
>   
>
>My thoughts exactly. Thankfully, I've managed to avoid the worst
>effects of the downturn in oil and gas because our clients are
>worldwide. I'm doing some collapse testing right now on some large
>samples for an Alaskan LNG pipeline.  Pretty impressive stuff to see 2"
>wall pipe bend like rubber in the big machines.Sean
>
>
>On November 6, 2015 6:36:00 PM MST, hank pronk via
>Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>Well, now is the perfect time to  bust out the cheque book because
>steel is as low as it is going to be according to EE  and they are
>pretty dead over there.Hank 
>
>
>On Friday, November 6, 2015 5:41 PM, Sean T. Stevenson via
>Personal_Submersibles<personal_submersibles at psubs.org> wrote:
>   
>
>No diesel. It will not operate independent of support capable of
>charging the batteries at the surface, though this may be accomplished
>by a portable generator if need be.It may be left in the water (towed,
>secured alongside, loaded and offloaded etc.) for the duration of an
>expedition, but is not intended for long-term submergence, such as
>seasonal operation.  Crane, A-frame or boat lift retrieval will be
>employed for storage and necessary maintenance.Sean
>
>
>On November 6, 2015 5:16:12 PM MST, hank pronk via
>Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>Do you intend on leaving the sub in the water full time (seasonal)
> Alsso sounds like it could have a diesel engine.Hank 
>
>
>On Friday, November 6, 2015 5:02 PM, Sean T. Stevenson via
>Personal_Submersibles <personal_submersibles at psubs.org>wrote:
>   
>
>Ambitious p! roject,subject to change as funding dictates. 4 person
>lockout submersible (pilot, supervisor, 2 divers). Large for a PSub,
>but sized for road / intermodal transport. Not ramp launchable.
>Operating depth of 600m, safety factor TBD. 48 hour mission, 72 hour
>reserve. Built to full ABS / GL compliance with documented tests (NDT,
>strain gauging, material and proof testing) to enable classification by
>engaging a surveyor in the future, but not classed at this time. When
>construction is completed, it will live in Vancouver - my second
>(first?) home.
>
>Sean
>
>
>
>On November 6, 2015 3:06:12 PM MST, hank pronk via
>Personal_Submersibles <personal_submersibles at psubs.org> w! rote:
>>Hi Sean,We have it all sorted! out,and they are going forward, my
>>minimum thickness should be .875 not bad!  
>>As for your project, are you releasing clues?     Hmmm  that means two
>>subs only 5 hr apart, nice!  Hank 
>
>
>_______________________________________________
>Personal_Submersibles mailing list
>Personal_Submersibles at psubs.org
>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
>   
>Personal_Submersibl! esmailing list
>Personal_Submersibles at psubs.org
>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
>_______________________________________________
>Personal_Submersibles mailing list
>Personal_Submersibles at psubs.org
>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
>  
>
>Personal_Submersibles mailing list
>Personal_Submersibles at psubs.org
>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>_______________________________________________
>Personal_Submersibles mailing list
>Personal_Submersibles at psubs.org
>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
>   
>Personal_Submersibles mailing list
>Personal_Submersibles at psubs.org
>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
>_______________________________________________
>Personal_Submersibles mailing list
>Personal_Submersibles at psubs.org
>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
>
>
>------------------------------------------------------------------------
>
>_______________________________________________
>Personal_Submersibles mailing list
>Personal_Submersibles at psubs.org
>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20151107/f58bd229/attachment-0001.html>