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Does it matter whether you pressurize a vessel from zero to 4000 psi in 40 millisecond or 10 hours? Will that affect the response of the tank wall in terms of the tensile stress in the wall during or after full pressurization.

Given I have a scenario where I'm making a large amount of gas in a closed chamber by reacting some chemical compounds. If the reaction takes place so fast that the vessel went from zero to 4500 psi in less than 1 second, how can I calculate (or at worst estimate) the thickness of steel wall of the vessel that can take the pressure surge and still remain intact with the gas contained. If you need further details, I'll be happy to provide.

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    $\begingroup$ Possible duplicate of Rapid Pressurization of closed containment $\endgroup$ – Solar Mike Feb 19 '19 at 21:39
  • $\begingroup$ Maybe not, check the update. $\endgroup$ – TechDroid Feb 20 '19 at 15:58
  • $\begingroup$ You should provide critical informat6ion about the material for example. $\endgroup$ – Solar Mike Feb 20 '19 at 16:16
  • $\begingroup$ A 40 ms jet of fluid can apply a higher pressure to the area it hits due to its momentum. Filling at the wrong speed might excite a resonance which might cause more stress. There are many phenomena like those that can happen in extremes. You should give more data. Is it really 40 ms? Also do you care about stress or failure? Some materials fail at lower stress with higher stress rates. $\endgroup$ – user1318499 Feb 20 '19 at 20:09
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    $\begingroup$ The common answer is no. Steel's strength and stress in normal use doesn't depend on loading rate. But your case might be different because of the various ways that it can matter. $\endgroup$ – user1318499 Feb 20 '19 at 20:31
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No, a gun barrel pressurizes rapidly yet the designs ( strength and thickness ) are based on the peak pressure independent of stress rate. Impact loading is different story and requires a blow from a solid object , not pressurization with a fluid. Hundreds of years ago cannon barrels were commonly made with cast irons for which a very strong case could be made that had low impact toughness , yet on average they performed well as gun barrels. The same can said of cast steel of that era; I promise you that Bessemer steels were not impact tough because of high nitrogen , phosphorus, and relatively high carbon ( and low manganese).I looked in an old reference for impact values but found none, apparently it was not worth even trying to measure on these old irons and steels.

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  • $\begingroup$ I updated the question with some further enquiry, I hope you can help with that. $\endgroup$ – TechDroid Mar 1 '19 at 2:14
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My answer is yes it affects if material of the vessel is rate dependent.

Some ductile materials behave brittle at high strain rates.

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