Stay spacing on jacketed cylindrical vacuum vessel
Stay spacing on jacketed cylindrical vacuum vessel
(OP)
Hello,
I'm struggling to make sense of UG-47 when also used with UW-19. I am trying to design a stainless steel jacketed cylindrical vacuum vessel, approx. 120" long, that can withstand 75 psig of pressure in the water jacket. With the external water pressure + vacuum my inner wall thickness is becoming a problem so I am trying to see what I can accomplish with welded stays in between the inner wall and jacket wall. When I used equation UG-47(a)(1) and solve for pitch (with a known thickness and pressure) I get 12.50", however UG-47(f) says no greater than 8.50". Furthermore in UW-19, the repeated term "required thickness of the plate" - it that referring to the stay plate which in my case in my inner vessel wall? In addition, can the stays in Fig. UW-19.2 per applied to a F&D head with a water jacket? I would think that if the stays are parallel to each other in one direction then they are providing zero reinforcement in the perpendicular direction and therefore become useless. Is there another way to treat the inner and outer head as a built-up section? Any guidance would be greatly appreciated. Thanks.
I'm struggling to make sense of UG-47 when also used with UW-19. I am trying to design a stainless steel jacketed cylindrical vacuum vessel, approx. 120" long, that can withstand 75 psig of pressure in the water jacket. With the external water pressure + vacuum my inner wall thickness is becoming a problem so I am trying to see what I can accomplish with welded stays in between the inner wall and jacket wall. When I used equation UG-47(a)(1) and solve for pitch (with a known thickness and pressure) I get 12.50", however UG-47(f) says no greater than 8.50". Furthermore in UW-19, the repeated term "required thickness of the plate" - it that referring to the stay plate which in my case in my inner vessel wall? In addition, can the stays in Fig. UW-19.2 per applied to a F&D head with a water jacket? I would think that if the stays are parallel to each other in one direction then they are providing zero reinforcement in the perpendicular direction and therefore become useless. Is there another way to treat the inner and outer head as a built-up section? Any guidance would be greatly appreciated. Thanks.





RE: Stay spacing on jacketed cylindrical vacuum vessel
In the pressure vessel code AD 2000 Merkblatt B6, 9 pages, cylindrical shell exposed to external pressure, incl. jacketed vessel.
And also AD 2000 Merkblatt B1, 2 pages, cylindrical shell with internal pressure.
They exist in German and English language.
For the english version of B6 please see: http://www.scribd.com/doc/208126692/AD-2000-MB-B6-...
For definitions you need also B0, 4 pages.
Look at this. They uses modern SI-units.
Best regard
Haralt
RE: Stay spacing on jacketed cylindrical vacuum vessel