[PSUBS-MAILIST] bolt in penetration

Alan James via Personal_Submersibles personal_submersibles at psubs.org
Sat Jan 10 16:07:05 EST 2015


Maybe it is being disgarded because it is out of testlike an old scuba tank! There may be markings on the sphere.If it fails hydro tests for internal pressure does that necessarilymean that it would be weaker when undergoing external pressure?Alan

      From: hank pronk via Personal_Submersibles <personal_submersibles at psubs.org>
 To: Personal Submersibles General Discussion <personal_submersibles at psubs.org> 
 Sent: Sunday, January 11, 2015 9:39 AM
 Subject: Re: [PSUBS-MAILIST] bolt in penetration
   
Sean,
I had Brian look for a plate and there is none.  I will start by trying to find the manufacturer through the university on Monday. 
Hank
--------------------------------------------
On Sat, 1/10/15, Sean T. Stevenson via Personal_Submersibles <personal_submersibles at psubs.org> wrote:

 Subject: Re: [PSUBS-MAILIST] bolt in penetration
 To: "Personal Submersibles General Discussion" <personal_submersibles at psubs.org>
 Received: Saturday, January 10, 2015, 3:15 PM
 
 If the university doesn't have the info, it
 should at least be traceable. All vessels built to ASME
 Section VIII Division 1 require a nameplate that will list
 the manufacturer, serial number, etc. Failing that,
 metallurgical tests are possible, but a bit more
 involved.
 Sean
 
 
 
 
 On January 10, 2015
 12:54:26 PM MST, hank pronk via Personal_Submersibles
 <personal_submersibles at psubs.org> wrote:
 Sean,
 Is
 there a on site test that can be done to determine the
 alloy?  
 Hank
 
 On Sat, 1/10/15, Sean T. Stevenson via
 Personal_Submersibles
 <personal_submersibles at psubs.org> wrote:
 
  Subject: Re: [PSUBS-MAILIST]
 bolt in penetration
  To: "Personal
 Submersibles General Discussion"
 <personal_submersibles at psubs.org>
 
 Received: Saturday, January 10, 2015, 2:46 PM
  
  Parallel projects... Sister
 subs... Could be
  fun.
 
 Sean
  
  
 
 
  
  On January 10, 2015
  12:19:38 PM MST, hank pronk via
 Personal_Submersibles
 
 <personal_submersibles at psubs.org> wrote:
  
  Yes but
 
 there two of them.
  Hank
  On
 Sat, 1/10/15, Sean T. Stevenson via
 
 Personal_Submersibles
 
 <personal_submersibles at psubs.org> wrote:
  
  Subject: Re:
 [PSUBS-MAILIST]
  bolt in penetration
  To: "Personal
 
 Submersibles General
 Discussion"
 
 <personal_submersibles at psubs.org>
  
  Received: Saturday, January 10, 2015, 2:16
 PM
  
  If it is suitable, I
 presume
  you're calling
 
  dibs?
  
  Sean
  
  
  
  
  
  On
 January 10, 2015
  12:10:14 PM MST, hank
 pronk via
  Personal_Submersibles
  
 
 <personal_submersibles at psubs.org> wrote:
  
  Sean,
  I
 may
  be able to on Monday.  The sphere
 was
  owned
  by a university
 and we can contact them to find the
  
 manufacturer.  Given that is was used as a
 
 pressure vessel
  paid for by a
 university
  working on a government project,
 I
  have to
  assume it is
 good stuff.  Not very scientific but a
  
 fair assumption at!
    this
 
 stage.  Luckily it is right in
  
 Brian's
  back yard in California so he
 was able to look
  at it and might be able
 to do some detective
  work.
 
  
 Hank
  On Sat, 1/10/15, Sean T. Stevenson
 via
  Personal_Submersibles
 
 
  <personal_submersibles at psubs.org>
 wrote:
  
    Subject: Re:
  [PSUBS-MAILIST]
  bolt in
 penetration
    To: "Personal
  
  Submersibles General
 Discussion"
  
 
 <personal_submersibles at psubs.org>
  
 
  Received: Saturday, January 10, 2015,
 2:02
  PM
    
    Hank, any chance you
  can
  find out what the alloy
  
 is? This will have
  a
 
 profound effect on its efficacy.
    Sean
    
    
    
    
    On!
  
 
  January
  10, 2015
    11:51:22
  AM MST, hank pronk
 via
  
 
 Personal_Submersibles
  
 
 
  <personal_submersibles at psubs.org>
 wrote:
    
    Sean, 
  
  
  Thank
 you, that is helpful.  My idea was
  to
  
  make the insert as t!
  ight as
  possible (sweat it
 in)  I a!
  m
  
 not
    sure if the difference in material
  would cause a problem
  
  though. The idea of
  seating
 the port into
  the shell a good
  
  option
 
 also.  I am just chewing the fat here, I have
  enough
    on my plate but it
 is
  fun to think
  about.  I
 was wrong about
    the size, the
  sphere is 6
  feet and I wrote
 60 in.  I imagine
    that
 
 kills the rating quite a bit?
    Hank
    On Sat, 1/10/15,
    Sean
 T.
  Stevenson via Personal_Submersibles
  
 
 <personal_submersibles at psubs.org>
  
  wrote:
    
    
 Subject: Re:
  [PSUBS-MAILIST]
    bolt in
  penetration
    To: "Personal
  
  Submersibles General
 
 Discussion"
  
  
  <personal_submersibles at psubs.org>
  
  
  
 Received: Saturday, January 10, 2015!
    ,
 1:40
  PM
    
  
    You could certainly!
  
  
 do
  that,
    although a
 three inch
    thick shell is pretty
  !
  
  
  substantial - I might consider
    
  machining
    eg. conical window
  seats in
 the
  hull sh!
    
  ell
    directly,
  and then
  derating the
 hull
    to a depth
  whereby
 the
    actual hull
  
  thickness is the effective
 
 derated thickness
    plus the effective
  reinforcement, which
  just
  
  happens to be a
    
  
 
 contiguous shell.  The
    bolt-in
  arrangement
  would not act
 as
    hull
  
  
  reinforcement though -
 unless it was a force fit in the
    hole.
 The idea of reinforcements around
  
 openings is to
    provide
  
 material around the
    hole to
  carry the shell
  hoop
    
  stresses that
    would
  
 
 otherwise have passed through the
    
  
 material in the opening, such that you
  
 don't increase
    the
 
 nominal shell
  stress. This requires a
    (relatively)
    smooth
 load
  path to redirect
  
  stress
  around the hol!
  e.
  Br!
  
 ian
    recently
    asked
 me
  about the
 
 effectiveness of reinforcements
    
  like perpendicular flanges lining the
 hole,
  
  and this is a
    bit complicated, because
 
 
  some
    stress i!
      s
  indeed
    
  
 
 redirected into
  such a flange, but the
 load
  is not evenly
    
  
  distributed as you move
 inboar!
    d or
    outboard
 away from the
    
  hull
  shell (with
  
  diminishing returns at
  
 increasing
    
  
 distances),
  and you also introduce a
 stress
  concentration
  
 at
    the
  perpendicular
  transition. Ideally,  
 reinforcements
  should
    
 be an effective
  
  
 thickening of the hull in the region
    
    immediately adjacent to
  the
 opening, tapered
  smoothly
 
  back
    (something
  like
 4:1) into the hull
  
  shell
 to provide
  a
    
  continuous load path
  
  with
  no stress
  concentrations at abrupt
  
 
  
  changes in geometry.
    Sean
    
  
 
    
    
  
  
    
  On
  
 January 10, 2015 8:25:39
  !
    
  
  AM
 MST, hank pronk via
 
 Personal_Submersibles
    
 
 <personal_submersibles at psubs.org>
  
 
  wrote:
    Is it feasible
 to
  
  have a
    bolt in penetration in a 3 inch
  thick sphere
    hull.  I
 am
    
  picturing machining
 a hole
  in
    the hull,
  then
  inserting a
    window housing
    with a
 shoulder!
  (flange)
 that fits tight in
    
  
 the hole and is bolted
  in
  
 place.  Can that arrangement
    act
    as reinforcement for
  the
 hul!
    l.
    
    Hank
    
  
 
  
  
  
 Personal_Submersibles
  mailing list
    
  
 
 Personal_Submersibles at psubs.org
    http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
  
  
    
 -----Inline Attachment
  
 
 Follows-----
    
    
    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
    
    -----Inline
 Attachment
  Follows-----
  
 
  
  
 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
  
  -----Inline Attachment
  Follows-----
  
  
  
 
 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
  
  -----Inline Attachment
 Follows-----
  
 
 
 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
 
 -----Inline Attachment Follows-----
 
 _______________________________________________
 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/20150110/0bab6df2/attachment-0001.html>


More information about the Personal_Submersibles mailing list