There is a standard plumbing tool that consists of a rubber plug with metal caps at both ends and a bolt running between; the bolt is sealed with rubber washers. Tightening the bolt expands the rubber plug and seals the opening. Obviously, this would need to be customized for your specific diameter and I am skeptical it will hold more than a few hundred psia. Ben's caution about differential pressure pertains. Bill Sent from my iPhone On Sep 9, 2014, at 20:31, Ben Brockert <wikkit@xxxxxxxxx> wrote: > I've seen Robert's approach used up to 600 psi or so. > > The lowest force approach is to make a plug rod that has a male gland > seal that fits into the throat. Retain it via whatever means are > convenient. > > It does mean that the wall just downstream of the throat has a > pressure on it that is much different than operational in the case of > a regen system, i.e. normally it would have near throat pressure just > downstream of the throat but instead it will be at atmospheric, so the > differential pressure between regen side and nozzle side will be > higher than operational. Closing out at the exit plane has the > opposite problem, giving no differential pressure between regen and > nozzle. > > > > On Tue, Sep 9, 2014 at 8:26 PM, Robert Watzlavick <rocket@xxxxxxxxxxxxxx> > wrote: >> My chamber has an open cap on the exit that closes out the regen cooling >> passages. For pressure/leak tests, I replace that open cap with a solid >> one. Mine only operates at 250 psi though. >> >> http://www.watzlavick.com/robert/rocket/regenChamber3/tests/dsc_1840m.jpg >> >> -Bob >> >> >> On 09/09/2014 07:31 AM, Peter Fairbrother wrote: >>> >>> Chamber for a bi-liquid, has a main joint at the top, several pipe entry >>> points etc. Operates (or should) at 2,100 psi, so even a tiny leak could be >>> disastrous - think Challenger. >>> >>> >>> I want to pressure-test it to maybe 3,500 psi, and was wondering if there >>> was a standard way to seal the nozzle for testing? >>> >>> Any other thoughts? >>> >>> >>> -- Peter Fairbrother >