Recent content by AndrewTravers

Maddocks Linear algebra and infinite series were never my strong suit in school, but I seem to recall that is what the math club used to put Zeno in his place. I suspect it would take longer to work out the math than it would to vent the vessel though, especially with all the minor effects in...

JL I've never run into those. Usually in my small part of the industry, they are using a snap acting plug style control valve (such as a Fisher D2 or D3, or a Norriseal 2275, or a host of other small valves) that is more commonly installed on a liquid dump line. In this case, though, there...

Thank you all for your help on this. Your collective guidance has helped me greatly in working this through, as well as raising a few points I had not considered sufficiently. The infinite low pressure blowdown time is, of course, erroneous, but at the same time, on the system I have in...

Thanks, I'll look for that. The constant time increment appears to be tied into the dp/P1 ratio for the valve sizing, which is near constant in the same run. This is a result of the increase in pressure losses at higher flows I think.

Thanks for spotting that btrueblood. It is supposed to be the difference in mass, not volume.

Good Morning All, I've been working on a customer request to determine the time it will take to vent a vessel we've supplied down to near atmospheric pressures using a blowdown valve. I've been sizing valves for about a decade, including blowdown valves, but have never seen any resources for...

owg, I'm not saying it's a bad idea, please understand. I'm just saying that it probably will be discarded as impractical, especially since they are fixated on -50 F and EG/Water mix isn't going to reach that far down. Just filling the vessel partway with EG/water may wind up being the...

Thanks to both of you. OWG I think the idea of hydrotesting the vessel just before start up would get discarded as being impractical, not least of which due to the temperatures involved (at least using water). However, if the liquid levels are then blown down by the process gas, the vessel...

Good Day, I'm on the hunt for suggestions and hopefully some references on how to start up a pressure vessel from a state colder than design. The vessel has an MDMT of -20 F, but the environmental conditions are such that parts of the vessel the vessel could be at an ambient temperature of...