[PSUBS-MAILIST] Penetrator Welds

[via Personal_Submersibles]

>From PVHO:
5.4.4 All the weld joints within plating and shell cut-out attachments are to be full penetration type with suitable groove/bevel. Penetrations into the shell are to be attached by full penetration groove and fillet weld. The leg length of the fillet should not be the less than the smaller of the thickness of the two parts being joined or as recommended by the applicable code.
Vance


-----Original Message-----
From: James Frankland via Personal_Submersibles <personal_submersibles at psubs.org>
To: Personal Submersibles General Discussion <personal_submersibles at psubs.org>
Sent: Fri, Jun 2, 2023 7:27 am
Subject: Re: [PSUBS-MAILIST] Penetrator Welds

Hi JonIve scoured ABS and i cant see anything specific about it.  Im sure its there somewhere, i just cant find it.
Ive just re-read my email and it might have been confusing.  I do mean small penetrators, not large penetrations such as viewports.  Obviously they must be 100% pen.
Anyone else got any ideas?
Thanks


On Fri, 2 Jun 2023 at 02:41, Jon Wallace via Personal_Submersibles <personal_submersibles at psubs.org> wrote:

 Reviewing ABS or ASME steel vessel rules may shed some light on the issue.  My understanding is that anything two inches or less requires only fillet welds.  The rule may actually be a ratio to the hull diameter rather than a specific number, however I do believe your 30mm penetrator is perfectly safe with fillet welds.
Jon


    On Thursday, June 1, 2023 at 09:39:45 AM EDT, James Frankland via Personal_Submersibles <personal_submersibles at psubs.org> wrote:  
 
 Hi All
Any thoughts on this.  I have always thought that welds for through hull fittings are not required to be full penetration.  Just keep the hole as tight as possible to the fitting.
Ive been talking to some people who say that the joints should be full pen.
Obviously full pen is best, but has issues with accessibility and warping.
On Jodie B i just welded all the penetrators in with a double fillet as i believe was shown in the plans.
Gamma plans show a "mostly" full pen weld for one of their penetrators.  See pic.
I am thinking of putting a 30mm diameter penetrator through the 25mm conning tower base.  This is a bit of a monster to get full pen.
What do you guys think?  Anyone put a penetrator through such thick material before?
Any views on penetration of small welded fittings?

_______________________________________________
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/20230602/3295c737/attachment-0001.html>