|
Great. Thankyou Jon and Carsten for clearning that up for me. -Scott Waters > Date: Sat, 11 Dec 2010 11:32:26 -0500 > From: jonw@psubs.org > To: personal_submersibles@psubs.org > Subject: Re: [PSUBS-MAILIST] Design depth > > > Carsten is absolutely correct here. You can't calculate failure depth > from operational depth. If you plug the K-350 design data into the > PSUBS hull calculator (thank you Cliff) you'll find that it's predicted > failure by calculation is somewhere around 875 feet. George applied a > 2.5x safety margin to limit max operating depth to 350 feet. > > If you know the max operating depth and the safety margin you can > calculate the failure depth, however you cannot assume either one of > those data points. The failure depth must be calculated either by > formula or FEA. Even then, it is a prediction not an absolute number. > > Jon > > > On 12/11/2010 4:47 AM, MerlinSub@t-online.de wrote: > > Hi Guys wrong way thinking! > > > > You have to know the failture depth and than reverse from that the maximum opertional and test depth. > > Without to know the failture depth you know nothing.. > > > > The calculation goes that way: > > > > 01) calculate failture deep > > 02) divided by minimum saftey factor (2,0) is operatioanl depth > > 03) mutiple by safty factor (1,25) is test depth > > > > Note that some sub designers use higher saftey factors because there 60-70ies calculations are only rough. > > Recalculation of this subs iwith modern analysis method may result in higher dive depths > > (or found conctruction mistakes). > > > > vbr carsten > > > > "Alan James"<alanjames@xtra.co.nz> schrieb: > >> Hi Scott, > >> I've heard that George Kitrige advised that his boats be tested to twice their operational depth > >> unmanned for an hour. So this would mean that there failure depth would be more than 700ft. > >> I'm not sure what their failure depth is; someone else may be able to help with this. > >> Regards Alan > >> ----- Original Message ----- > >> From: Scott Waters > >> To: psubs > >> Sent: Saturday, December 11, 2010 3:12 PM > >> Subject: RE: [PSUBS-MAILIST] Design depth > >> > >> > >> I'm confused, haha. So on a K-350, the operating depth is 350 feet and the test depth would be 437.5 feet (multiplied by 1.25) > >> and the failure depth would be 600 feet? I'm just trying to understand the thread of posts. > >> -Scott Waters > >> > > > > > ************************************************************************ > ************************************************************************ > ************************************************************************ > The personal submersibles mailing list complies with the US Federal > CAN-SPAM Act of 2003. Your email address appears in our database > because either you, or someone you know, requested you receive messages > from our organization. > > If you want to be removed from this mailing list simply click on the > link below or send a blank email message to: > removeme-personal_submersibles@psubs.org > > Removal of your email address from this mailing list occurs by an > automated process and should be complete within five minutes of > our server receiving your request. > > PSUBS.ORG > PO Box 53 > Weare, NH 03281 > 603-529-1100 > ************************************************************************ > ************************************************************************ > ************************************************************************ > |