seal design for water tighness (3 meter depth)

[Herb50]

I need to design a seal on a plastic (pc/abs comp)for an application that may see submersion in water of up to 3 meters.  Is there a good reference source?  I haven't seen any in my searches.

 

[MoldMaker]

Hi Herb50,<br><br>I just turned 50 as well, could you elaborate a little on geometry, such as what you are looking for? screw fits, &quot;O&quot;-ring, U/sonic welding, UV glue joining, how many different parts and are they the same materials and other responses like that.<br>If you want basic fit to fit and expect it to seal, you are going to have to do a lot of mold-tuning and part de-bugging but one thing only will be guaranteed, that the 2 parts can not be movable or water will find it's way in no matter what.<br>I know this has no wonderful answers, however if there are no questions there are no directions.<br>

 

[Herb50]

The design is for a cover for an electronics box.&nbsp;&nbsp;The material proposed is a pc/abs composite.&nbsp;&nbsp;The cover needs to be removeable, so no ultrasonic sealing or glue can be used.&nbsp;&nbsp;We've discussed RTV, but I don't like it.&nbsp;&nbsp;An o-ring is a possibility, but the geometry is not friendly.&nbsp;&nbsp;A flat gasket has also been considered.&nbsp;&nbsp;The problem is an even distribution of mounting hardware to control o-ring or gasket compression.<br><br>The cover is about 4 x 3.5, and is screwed in place.&nbsp;&nbsp;O-rings will be used on the mounting hardware.&nbsp;&nbsp;I've been trying to work out some sort of snap-on lid, which would provide o-ring preload.&nbsp;&nbsp;I've searched for design guides on the web, but haven't found any of use.&nbsp;&nbsp;I expect experience with this type of desing is better than any design guide. Unfortunately, I have limited experience in sealing and in plastics design, especially snap-on features any help is appreciated.

 

[Justy]

I am currently seeking information on this topic as well.

I need more information with regard to seal design.

Two shot molding I have found some information on the GE Plastics site but require more information can someone help me please.

Cheers Justy

 

[troppo]

hi justy
your local o'ring supplier should be able to provide you with o'ring groove specifications for static and dynamic sealing these are fairly standard.If you are machining o'ring grooves in plastic you will need to reduce the dimensions in compression slightly as plastic has more movement than steel which is what most spec's are written for.
i have made a few housings and the most reliable has always been the tube and end cap design.
end caps having both an axial and face seal with stainless clips holding the end caps on It has always been a issue with electronic boards being square and tubes being round with bouyance and size being the main issue.
i personally don't trust electronic boxes being converted into underwater housing(if they don,t leak the first time they usually do the second time) the best box housing is one that has been fabricated for the job the best material for this is acrylic with uv glue joints.
if you want one built seek out a underwater camera housing fabricator another option is to go to a dive shop as they stock underwater housings in various sizes from different manufacturers.(you get what you pay for)
hope this helps

 

[sas]

This is my first entrance and I hope that I will enjoy. The thing I want to know is I am interesting to design a cap for HDPE bottles without thread. So please let me know tht how can I best design the cap without any threas , its just like one push closure and one push opener.
Regards