In house external pressure testing

Do you have a means of water pressure depth testing for 4" x 12" WTE’s at your facility? A hydrostatic test chamber.

Hi @model14,

I asked about this internally and apparently we do have the capability to test enclosures of that size at one of our facilities, but

If you’re looking to test something of your own, note that we usually don’t have available capacity to run tests for uses outside the company.

The Under Pressure pressure vessel design software may be helpful for at least determining a theoretical pressure limit :slight_smile:

When your specs say a 4" tube is rated to 150m, is this based on calculations or empirical data?

Both. Calculations give a theoretical maximum depth limit, and pressure tests can be either “to failure” (which we’re more likely to do in open water, for safety reasons) to give a tighter maximum limit, or “to success” to give a weaker bound on what is at least confirmed to work for a given sample.

Any rating is statistical (i.e. even if we pressure tested every component that goes out the door it could in principle fail on a future pressure cycle, not least because materials and components degrade over time / with use), but our ratings are provided from at minimum a theoretical calculation and an indicative test of a similar/representative component (e.g. enclosure tubes with the same material, diameter, and wall thickness tend to behave predictably across similar lengths). Depending on the confidence we want and/or how close we want to push a component to its theoretical limit we may do a variety of additional tests (e.g. higher sample numbers, and/or system tests in conjunction with several other components) before deciding on a rating.

I would note that our testing capabilities are continually improving, and occasionally after additional testing a rating may change, which is then reflected in the Revision History section in the Technical Details of the relevant product(s).

As a couple of examples:

Very informative, thank you.

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