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Recent content by simmantix

  1. simmantix

    Pressure Thrust into a larger chamber..

    Sorry, are you saying a bellows installed at free length will not axially compress under vacuum? Simmantix --------- Phases of a Project: Exultation, Disenchantment, Search for the Guilty, Punishment of the Innocent, Praise for the Uninvolved...
  2. simmantix

    Pressure Thrust into a larger chamber..

    Just to re-iterate, its a vacuum system with a bellows joining the pipe to the chamber. I want to design the tie-rods or perhaps put in a pressure balancing joint so.. My question is: what is the force acting to collapse the bellows due to the vacuum within the system? Awful drawing attached...
  3. simmantix

    Pressure Thrust into a larger chamber..

    Sorry, meant thrust pressure.. Simmantix --------- Phases of a Project: Exultation, Disenchantment, Search for the Guilty, Punishment of the Innocent, Praise for the Uninvolved...
  4. simmantix

    Pressure Thrust into a larger chamber..

    Hi, If I have a pipe connecting to a 750mm diameter vacuum chamber via an unrestrained 500 mm diameter bellows, can someone confirm that the thrust pressure that would work to collapse the bellows under vacuum would be based on the diameter of the bellows and not the chamber? I am pretty sure...
  5. simmantix

    Working with Matrices in MathCad

    Fair enough but if I wanted an array of partial pressures, same units then how would I populate the second column? Simmantix --------- Phases of a Project: Exultation, Disenchantment, Search for the Guilty, Punishment of the Innocent, Praise for the Uninvolved...
  6. simmantix

    Working with Matrices in MathCad

    So.. Additionally, is it possible to fill each column of the array with different data in the same way as above. So the first column would be P1, the next P2 and so on? Or do you have to create seperate arrays and Append them together? Thanks, james Simmantix --------- Phases of a Project...
  7. simmantix

    Working with Matrices in MathCad

    Thankyou, succinct and to the point.. Simmantix --------- Phases of a Project: Exultation, Disenchantment, Search for the Guilty, Punishment of the Innocent, Praise for the Uninvolved...
  8. simmantix

    Working with Matrices in MathCad

    Hi, Hoping someone here can help.. I have a equation, say: P=(q*t^a)/S I want to vary P with t and I would like to populate the first column of an array with t values, say 1..75 (range variable) and then populate the second column with P assuming q, a and S are static. Then I would want to...
  9. simmantix

    Minimum sample size

    Hi again, Here's hoping that Greg or someone is still interested? So Greg, thanks for your spreadsheet, it helped me make my own and taught me more about normal distributions, etc. than I ever thought I would want to know. Only in doing these sheets, etc. have i learned more about the actual...
  10. simmantix

    Minimum sample size

    What confidence do you need to work to? 95 or 99% Are you prepared to measure a few to get an idea of the stats and then take more samples if necessary? No.. Maybe but they just want to do a number that's worth doing and that's it Are you confident that all 250 are from the same population and...
  11. simmantix

    Minimum sample size

    Hi, If I have, say, 250 components and they may or may not have defects bigger than a specification I built up from some empirical evidence on the subject, how do I work out how many components ( hopefully less than 50) I need to scan for defect sizes in order to statistically validate my...
  12. simmantix

    Anyone know of a Fire Electro/Pneumatic Cuttoff (fusible link?)?

    Hi all, I have a gate valve that I am testing in order to use it as a fire damper. The valve is air open/air close but it will also close under gravity thus the loss of pneumatic pressure, totally or to the Open connection, would (slowly)close the valve. I have to electrically link the damper...
  13. simmantix

    Monte Carlo Simulation

    sorry?? Simmantix --------- Phases of a Project: Exultation, Disenchantment, Search for the Guilty, Punishment of the Innocent, Praise for the Uninvolved...
  14. simmantix

    Monte Carlo Simulation

    OK then.. You should find everything you need here: http://www.elsl.co.uk/assets/files/mcsim.zip Please do me the kindness of posting or e-mailing me if you take a copy so I can issue updates if neccessary.. Thanks Jim Simmantix --------- Phases of a Project: Exultation, Disenchantment...
  15. simmantix

    Monte Carlo Simulation

    If anyone still wants this I will put it on a new website?? Anyone interested? Jim Simmantix --------- Phases of a Project: Exultation, Disenchantment, Search for the Guilty, Punishment of the Innocent, Praise for the Uninvolved...

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