off shore electronics housing

[rmetzger]

We're looking into manufacturing a housing for a offshore application (submersed in seawater) and I'm looking for a few options. Currently the design calls for a plastic housing but the tooling on the production units is very high. Staying with this type of concept I was looking at material suggestions that will both be corrosion resistant, dimensionally stable, and be impact resistant as undoubtedly something will find a way to bang against our device. Toping my material list is HDPE.

As an alternative I was looking at different alloys as a cast-able option. We have a casting house that may be able to help us with the tooling but their primary material is aluminum (not generally suitable). Is there any low melting point alloys (<1200 F) that may serve as a suitable substitute for this application. Any recommendations are helpful.

 

[rorschach]

you say submerged, but you do not state the depth. one thing we did in the ROV industry was to buy off the shelf fiberglas housings and port them to the hydraulic system to maintain a slightly positive pressure inside the housing (around 5-10 psi or so)relative to the external pressure. the downside to that is you have to be careful about the electronics to make sure they can handle the pressure. on the plus side, the oil did a pretty good job of keeping the electronics cool. for the electonics that could not withstand being immersed in hydraulic fluid at pressure, we had to build a pressure vessel (we went pretty deep so we used titanium) to keep the laser gyros and such in. was not an off the shelf item!

 

[rmetzger]

I'll be submersed in less than 100ft of depth in operation and the design will not lend itself to external sources of power or pressurization.

 

[rorschach]

6061 Aluminum if hard (Mil-spec Type 3 class III if memory serves) anodized and sealed works fairly well offshore. Also gives you a nice surface for o-ring seats. That's what we used for our hyd. manifolds. Not sure what an equivalent casting alloy is.