Hi - It appears I have a small leak through a potted penetrator cable. I discovered this when I first noted that I was losing vacuum pressure slowly, then by pressurising the housing and spraying with dilute soapy water, I saw bubbles forming from one cable penetrator. Ideally I would replace this with a compressed gland type, but getting them here (Falkland Islands) would take many weeks at best. In the mean time, I have an epoxy sealant kit that was purchased for ROV cable repair I believe - G/Flex 650-K Epoxy (https://www.paintmarine.co.uk/west-system-gflex-650-k-epoxy-repair-kit-48002-p.asp). If I applied this epoxy covering the area where the cable enters the penetrator, would this be a suitable fix for now while I wait for new compressed gland types? Any advice welcome! Many thanks!
Hi Paul - a solution like that might work for a temporary fix, but if you’re planning to go to significant depths or for many hours, I would expect to have some water to worry about. A Wetlink Penetrator is definitely the best long-term solution!
You could apply your epoxy on both entry and exit, although if you get it on the internal threads it can be tough to remove the nut later! Good surface prep, cleaning the surface with alcohol or acetone and allowing it to fully dry can help. After applying the epoxy work the cable around so it can penetrate any gaps. You can mitigate the risk if you know you might have a slow leak by adding paper towels at the rear of the enclosure, to keep the water from sloshing around and shorting out components. Depending on how long you go before you get a leak-deteted alarm, you may still be able to accomplish your goals… Best of luck!
Good field tips from Anthony!
For surface prep, sand the bonding areas with 150 grinding paper.
Glue and let harden.
For extra safety, make more elastic extra safeguard:
Sand and clean the now hardened epoxy area on the outside of penetrator.
Put on one component marine sealant like Sikaflex 291
Thanks @Boko and @tony-white for good advice. I’ll make the those temporary fixes and order the Wetlink penetrotors asap. Not deep depths or for long periods so that should be ok for next job.
I wondered about the epoxy sealing/bonding around the cable itself - is the cable silicone? If so, do you think the epoxy + Sikaflex combo would work on silicone?
BR cables are like most UV professional cables Polyuretan in the outer shell (often called PUR)
If you have silicon cables gluing is hard as you say.
PUR can be glued, problem is that it is flexible (also meant to be) and therefore glue should be flexible as well. Otherwise you get a brake where the bending occur.
I have used temporary fixes like above to hundreds of meters.