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End cap depth rating

Hi can you tell me what the 14 hole endcap depth rating is? It doesn’t specify in the technical details. Thanks, Tim

@TimZ You are correct, we haven’t assigned absolute depth ratings to many of the WTE components as we are still testing and deciding on a depth rating with a safety margin.

From our testing of the 14 hole endcap, a permanent deformation occurs at 350m and fails at 450m.

How about the 18 hole?

I gotta be honest, I thought that when you added the aluminum housing the next weakest link was the dome and the assembly would then be rated to 500m, but it sounds like the aluminum housing basically does nothing to improve the depth rating of the assembly.

18-Hole Endcap has an assigned depth rating: https://bluerobotics.com/store/watertight-enclosures/4-series/wte4-m-end-cap-18-hole-r2-rp/#tab-technical-details

Each of the components has different depth ratings based on their material and construction.

We have theoretical failure depths for all components (some aren’t listed right now), but we have not completed empirical failure testing on everything yet. Once we have a good gauge on failure depth averages using the Crushinator, then we can assign our own depth ratings.

In the future we intend to have something like a WTE calculator on the website where someone can select the components you want and then it will come out with a depth rating for the WTE based on the weakest component.

Thanks Kevin. Another question, did you guys re-rate your 4" aluminum tube?

The 4" tube had a theoretical depth rating when it was introduced. A few months ago we re-rated it after doing our empirical testing and had a few that got crushed at 450m.

You’re killing me here. Was it 500m before? Was there a bulletin on this? If it was de-rated and no bulletin, that’s not cool. Is it out of stock because it’s being redesigned? If it’s being redesigned, is there going to be an exchange?

Correction to my last, the aluminum 4" WTE tube has always been 400m, it was the 3" that got readjusted from 500m to 400m.

This is the screenshot from our old documentation, it has always been 400m.

Thanks for clarifying. I’d still like to know if there was a bulletin? If not, there really should be anytime a pressure rating is lowered.

I think the 3" and 4" are of similar design with the weight saving pockets between the center and each end. When they fail, do they fail in those pockets?

Still not quite understanding all this. The 4" enclosure has always been 400m, but the 4" 14-hole end cap permanently deforms after 350m? What are the theoretical ratings for the 3" blank end cap and the 3" 4-hole end cap?

Sorry, for the confusion, our WTE components haven’t had much love on testing/documentation side in the past. Hence, a lot of the theoretical and lack of established depth ratings. Each component will have different depth ratings. Therefore, the whole assembly will have a depth rating based on the weakest component.

We are actively working on testing and a new configuration page. We’d like to get to a point where once you select an assembly, it will output the depth rating. The store isn’t set up to handle this at the moment.

Once we are confident on the failure points, we’ll be deciding on an appropriate safety margin, and then subsequent depth rating for each component.

Theoretical for the 3" blank end cap is 697m according to Under Pressure, however, we haven’t been able to bend one down to the max we can test, 975m
The Under Pressure doesn’t do holes very well so we don’t have a theoretical offhand, but we haven’t been able to bend one down to the max we can test, 975m

If you need to get to 400m with a 4", you are looking at an 18-hole end cap and a dome or some combination of that. The 18-hole has additional reinforcement that the other endcaps do not.

If this isn’t satisfactory for your requirements while we get ratings assigned, please contact sales@bluerobotics.com and we can do a return for your items.

Thanks Kevin. I don’t need to return parts, just needed the information because tells what all needs to be sorted out. I have some 14-hole end caps being made in 3/8", which I’m hoping is good enough to match the dome, then I’ll order some 1/4" wall tubing with 3" & 4" ID and add a little buoyancy and be all set.