[PSUBS-MAILIST] cable fittings

Sat Jun 20 08:31:06 EDT 2020

Rick, in my experience, in industry, when people say strain relief they're
usually talking about an extra physical component to the fitting which
strengthens the cable from bring physically pulled/stressed. Normally this
component is not associated with the pressure sealing capability of the
fitting. Using that term when talking to the vendors might be confusing.

On Sat, Jun 20, 2020, 12:29 AM Rick Patton via Personal_Submersibles <
personal_submersibles at psubs.org> wrote:

> Brian
>
> Not sure to tell you the truth. I may be calling it the wrong thing. The
> Blue Globe fittings that others have mentioned is what I want and I have a
> call out to the Vendor that carries that German fitting to see if I can get
> it in a 3/8" NPT for the rating that I want. Also reaching out to Contaclip
> as Sean and some others have mentioned. I was going to do a test today on
> the SealCon fittings that I bought a few years ago that have a 10 bar
> rating to see at what pressure they extrude but wasn't able to.
> Hopefully tomorrow. I'll let ya know the results.
> Rick
>
> On Fri, Jun 19, 2020 at 5:55 PM Brian Cox via Personal_Submersibles <
> personal_submersibles at psubs.org> wrote:
>
>> Rick,         Isn't there a difference between strain relief and just a
>> straight compression fitting ?
>>
>> Brian
>>
>>
>>
>> --- personal_submersibles at psubs.org wrote:
>>
>> From: Rick Patton via Personal_Submersibles <
>> personal_submersibles at psubs.org>
>> To: Personal Submersibles General Discussion <
>> personal_submersibles at psubs.org>
>> Subject: Re: [PSUBS-MAILIST] cable fittings
>> Date: Fri, 19 Jun 2020 03:20:56 -1000
>>
>> Brian
>> sorry I didn't answer sooner as been crazy. I will be passing a
>> depth sounder wire, a UTC underwater comms transducer wire, a VHF
>> radio antenna cable and LED lights which is about 5/16" diameter with 4
>> insulated wires inside of it.
>>
>> Rick
>>
>> On Mon, Jun 15, 2020 at 10:41 AM Brian Cox via Personal_Submersibles <
>> personal_submersibles at psubs.org> wrote:
>>
>> Rick,         What are you trying to run through there?
>>
>> Brian
>>
>>
>>
>> --- personal_submersibles at psubs.org wrote:
>>
>> From: Rick Patton via Personal_Submersibles <
>> personal_submersibles at psubs.org>
>> To: Personal Submersibles General Discussion <
>> personal_submersibles at psubs.org>
>> Subject: Re: [PSUBS-MAILIST] cable fittings
>> Date: Mon, 15 Jun 2020 06:50:04 -1000
>>
>> Just called Sealcon to confirm how they rate their strain relief fittings
>> and they base it on line pull so the ones I have won't work. they said that
>> they also sell a cable clip that attaches to the cable on the pressure side
>> to keep it from extruding so I might but one of them and do some testing to
>> see if this will be an option or not.
>> jRick
>>
>> On Tue, Jun 9, 2020 at 6:00 AM Alan via Personal_Submersibles <
>> personal_submersibles at psubs.org> wrote:
>>
>> Ian,
>>
>> https://www.macartney.com/what-we-offer/systems-and-products/connectors/subconn/
>> I'm not sure how you get Psub discount. I got some through Jon the
>> facilitator / owner
>> of the group a long time ago.
>> He normally reads the emails & will comment if you have a question.
>> There may be an email link to Jon, or more info on the Psub web site.
>> He's based in NY, so just a submarine ride away!
>> Cheers Alan
>>
>> On 10/06/2020, at 1:07 AM, Ian Juby via Personal_Submersibles <
>> personal_submersibles at psubs.org> wrote:
>>
>> :O  That's them!  Subcon eh? I'll look them up. Psubs gets a discount?
>> How does that work?
>>
>> Ian
>>
>>
>> On Mon, Jun 8, 2020 at 6:46 PM Alan via Personal_Submersibles <
>> personal_submersibles at psubs.org> wrote:
>>
>> Thanks Ian,
>> I have those type of penetrators (below). Psubs gets a discount from
>> subConn
>> that makes them.
>> Would be a bit difficult making them yourself & the bought ones have a
>> securing
>> device so they can't pull apart ( orange thing in photo).
>> I agree that there wouldn't be much call for wet mating them, & that it
>> would just
>> be an opportunity for corrosion.
>> Alan
>>
>> <image1.JPG>
>>
>> On 9/06/2020, at 5:43 AM, Ian Juby via Personal_Submersibles <
>> personal_submersibles at psubs.org> wrote:
>>
>> Hi Rick,
>> I saw your post and wanted to ask if you meant electrical or plumbing
>> through hull connections. So I'm glad you reposted because I haven't been
>> able to follow the thread, nor have I had the time to go back and look
>> stuff up.
>> When I was working R&D on our diver heater system, we used a watertight
>> bulkhead connector for the shot line and remote control. Unfortunately,
>> this was over 20 years ago and I was not the one who actually ordered the
>> connector. So I innernets'd some pictures to try and hopefully find it
>> again because I remember quite well what it looked like, its design and
>> construction. The closest thing I could find was Teledyne Marine's "Wet
>> mate" connectors:
>> http://www.teledynemarine.com/electrical-wet-mate-connectors/
>> I couldn't tell you the price, but I'm sure they weren't cheap. For my
>> ROV project, I'm still in the rough design phase and I keep increasing its
>> depth capabilities. So I'm just going to make my own through-hull
>> connectors, and they will be similar to this design.
>> The through-hull seal is accomplished by a simple and reliable o-ring
>> (which doesn't appear in teledyne's picture). Basically, the rubber
>> connector body is mounted to a brass threaded tube that goes through the
>> bulkhead. The brass threaded tube has a seat for an o-ring which gets
>> compressed by both the nut and external water pressure. Here, I drew a
>> pretty picture:
>>
>> <bulkhead connector.jpg>
>> I just realized I didn't mark the brass tube, but it's the part that goes
>> through the bulkhead.
>> The particular connector we were using only needed to go to like, 300
>> feet. I believe we tested the heater unit to 300 psi and ironically, it was
>> the swagelock fittings inside the unit that leaked - that electrical
>> connector never leaked. We had I think 8 electrical connections passing
>> through that? We could get the identical connector as a straight-through
>> connector, and not an angled connector like my drawing.
>> The pins and sockets were the solid style - in other words there was no
>> splits to allow for expansion or contraction of the sockets or pins. This
>> further added to the waterproof nature as now the wire (a possible leak
>> point) was buried in solid rubber, behind a solid metal socket which itself
>> was buried in solid rubber. Any water wicking along would have to travel
>> 1/2" along the metal/rubber just to get past the socket.
>> The connector body was a hard rubber, both the through-bulkhead block and
>> the male connector. Under high pressures, the water can wick along the
>> inside of the wires (between the copper and the outer insulation) or if you
>> pass the wire through say, silicone rubber, it can wick along the junction
>> of the outside of the wire and the encasing rubber. So the longer that
>> travel distance is, the higher the pressure needs to be to force water
>> through those avenues. That rubber block was only maybe 2 inches left to
>> right in my drawing. I don't remember what pressures or depths it was rated
>> for, but I guarantee you it could take a LOT of pressure. Mechanically
>> (because the bulkhead hole was small) and in keeping watertight. The
>> biggest risk for a leak was if the bulkhead got a scratch where the o-ring
>> seated against it. I have no doubt that connector could have taken
>> hydraulic pressures (thousands of PSI).
>> I did not draw this in my pretty picture, but the head of the brass tube
>> probably had multiple rings inside the rubber, both to get good mechanical
>> locking between the rubber body and the brass body, and to make the
>> greatest distance the water would have to travel to get around from outside
>> to inside the tube, if it were to wick along the junction between brass and
>> rubber. But I'm speculating there because I didn't cut one of those
>> connector$ open to find out. Lest I get fired and stuff for destroying a
>> connector worth hundreds of dollars, you know.  :D Just, when I go to make
>> my own connectors, I'll be making the mounting tube like that, for those
>> reasons. The rubber that made up the connector body filled everything,
>> including right to the bottom of the brass tube.
>> The nice thing about making your own connector as well is that you can
>> make the electrical pins, sockets and wires any size you want to match your
>> electrical current needs.
>>
>> These particular connectors could be plugged and unplugged underwater,
>> but I suspect it would be very difficult to do as it would have to displace
>> water or vacuum from the connector holes. But as you can see, the male pins
>> had insulating rubber for a part of their length to maximize the distance
>> the electricity would have to travel from pin to pin, thus maximizing the
>> electrical resistance from pin to pin as well.
>> Hope that helps,
>> Ian
>>
>>
>> On Mon, Jun 8, 2020 at 12:09 PM Rick Patton via Personal_Submersibles <
>> personal_submersibles at psubs.org> wrote:
>>
>> I posted the other day about cable threw hull water tight fittings and
>> only got one response back and was hoping for more feed back as I know most
>> of you probably don't make your own so for the ones that buy them, is Blue
>> Globe the only player out there besides sealcon?
>> Thanks
>> Rick
>> _______________________________________________
>> 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:///eonapps/ft/wm/page/compose?send_to=Personal_Submersibles%40psubs.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:///eonapps/ft/wm/page/compose?send_to=Personal_Submersibles%40psubs.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/20200620/50a0d1aa/attachment-0001.html>