<html><head></head><body><p dir="ltr">6-8 mm is plenty, provided you can accurately locate the center between them. A channel for oil / pressure communication doesn't need to be more than 1/8". The "ultimate" implementation I described in a previous message would still be my no holds barred solution, but it occurred to me that you could approximate the same behaviour without the second compensator by simply using an in-line check valve with a known cracking pressure. If there is enough meat in the housing to accommodate e.g. a 1/8 NPT Swagelok fitting to provide a connection to that inter-seal space, then you could pipe the air compensation to the main motor housing at ambient pressure + a bias pressure as previously discussed. If, however, that bias pressure is equal to the cracking pressure of the check valve, then you could also tee off that supply line, through the check valve, into the inter-seal volume. This would compensate it at approximately ambient pressure without
requiring a separate unbiased compensation source in addition to the biased one. Any accumulated overpressure would just blow past the seal lip.</p>
<p dir="ltr">Sean<br>
</p>
<br><br><div class="gmail_quote">On April 10, 2017 8:30:45 PM MDT, Jon Wallace via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<pre class="k9mail"><br />It is on the RIPTIDE MK101 although it looks like you'd have to drill <br />through the outside of the housing to get access to the void and then <br />seal the outside shell somehow. You'd also want to measure twice before <br />drilling...I think there's only about a 6-8mm void between the seals.<br /><br />Jon<br /><br /><br />On 4/10/2017 7:30 PM, Sean T. Stevenson via Personal_Submersibles wrote:<br /><blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #729fcf; padding-left: 1ex;"><br /> Is it possible to drill and port a channel to the inter-seal volume on <br /> one of those motors?<br /><br /> Sean</blockquote><br /><br /><hr /><br />Personal_Submersibles mailing list<br />Personal_Submersibles@psubs.org<br /><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br /></pre></blockquote></div></body></html>