Dimple Jacketed Vertical Full Vacuum Tank Code Design
Dimple Jacketed Vertical Full Vacuum Tank Code Design
(OP)
Could someone help me with my Dimple Jacketed Vertical Full Vacuum Tank Code Design please:
Material: T304 SS, Dia. of 72" and straight shell of 78", D & F heads at the ends, tank internal design pressure : full vacuum (-14.7 psi) at 250F degree, dimple jacket: 45 psi, 250F degree hot water, dimple jacket divided into three zones, two for side wall with a height of approxi. 36" full circuferenced coverd respectively, and one for bottom full covered (to reduce volume of each zone for avoiding Pressure Vessel Regulation)
I used the TSSA registed dimple sheet 14 Ga, (as per UG-101 & UG-47, maximium dimple design pressure: 150 psi at 300F degree with a minimum backing plate(tank shell) thickness of 10 Ga (0.1406").
As per UG-28, formula: Pa = 4B/3(Do/t), If I assume design thickness of the tank shell is 1/4", should I use t = 1/4" or t = 1/4" - 0.1406 = 0.1094" to verify Pa for tank inner pressure? (In other words, should I conside the design pressure as 14.7 + 45 = 59.7 psi for a external pressure vessel or just use 14.7 psi to perform calculation since this is braced and stayed members in accordance with paragraph UG-47.
Material: T304 SS, Dia. of 72" and straight shell of 78", D & F heads at the ends, tank internal design pressure : full vacuum (-14.7 psi) at 250F degree, dimple jacket: 45 psi, 250F degree hot water, dimple jacket divided into three zones, two for side wall with a height of approxi. 36" full circuferenced coverd respectively, and one for bottom full covered (to reduce volume of each zone for avoiding Pressure Vessel Regulation)
I used the TSSA registed dimple sheet 14 Ga, (as per UG-101 & UG-47, maximium dimple design pressure: 150 psi at 300F degree with a minimum backing plate(tank shell) thickness of 10 Ga (0.1406").
As per UG-28, formula: Pa = 4B/3(Do/t), If I assume design thickness of the tank shell is 1/4", should I use t = 1/4" or t = 1/4" - 0.1406 = 0.1094" to verify Pa for tank inner pressure? (In other words, should I conside the design pressure as 14.7 + 45 = 59.7 psi for a external pressure vessel or just use 14.7 psi to perform calculation since this is braced and stayed members in accordance with paragraph UG-47.




