Vessel Thickness Calculation
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Formula in Input Req. P Input Req. S Input Req. E Input Req. E Input Req. R Input Req. D t Input Req. C.A. Cylindrical Shell (Lon Answer t Answer t+CA Sphere and Hemisph Answer t Answer t+CA Ellipsoidal He Answer t Answer t+CA Cone and Conical Input Req. alpha Answer t
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pressure vessel
Transcript of Vessel Thickness Calculation
Formula in terms of internal diameter
Input Req. P Design PressureInput Req. S Allowable Stress Value
Input Req. E
Input Req. E Efficiency of seamless head
Input Req. R
Input Req. Dt Required wall thickness
Input Req. C.A. Corriosion allowance
Cylindrical Shell (Long Seam)
Answer t PR/(SE-0.6P)
Answer t+CA PR/(SE-0.6P)+CA
Sphere and Hemispherical Head
Answer t PR/(2SE-0.2P)
Answer t+CA PR/(2SE-0.2P)+CA
Ellipsoidal Head
Answer t PD/(2SE-0.2P)
Answer t+CA PD/(2SE-0.2P)+CA
Cone and Conical section
Input Req. alpha One half of the apex angleAnswer t PD/(2cos@(SE-0.6P))
Efficiency of spot examined joints of shell and hemis head to shell
inside radius(In corrison condition greater with the corrsion allowance)
inside diameter(In corrison condition greater with the corrsion allowance)
Answer t+CA PD/(2cos@(SE-0.6P))+CA
ASME flanged and dished head(Torrisherical Head)When L/r ratio is equal to 16 2/3
Answer t 0.885PL/(SE-0.1P)
Answer t+CA 0.885PD/(SE-0.1P)+CA
ASME flanged and dished head(Torrisherical Head)When L/r ratio is less than 16
Input Req. r Knuckle radiusAnswer L/r Less thann 16 2/3From table M 1.75Answer t PLM/(2SE-0.2P)
Answer t+CA PD/(2SE-0.2P)+CA
Formula in terms of internal diameter
200 psi 13.793103 bar 14.0647 kgf/cm^217500 psi A 515 gr 70 at 650C
0.85
1
48 inches 1219.2 mm 196.850393700787
96 inches 2438.4 mminches
0.125 inches 3.175 mm
For the new condition0.652 inches 16.57 mm From the table tm0.777 inches 19.74 mm SEt/(R+0.6t) P
For the new condition0.324 in 8.23 mm From the table tm0.449 in 11.40 mm 2SEt/(R+0.2t) P
For the new condition0.551 in 13.99 mm From the table tm0.676 in 17.16 mm 2SEt/(D+0.2t) P
30 deg. For the new condition0.753 in 19.13 mm From the table tm
0.878 in 22.31 mm 2SEtcos@/(D+1.2tcos@) P
ASME flanged and dished head(Torrisherical Head)
For the new condition0.973 in 24.72 mm From the table tm1.098 in 27.90 mm SEt/(.885L+0.1t) P
ASME flanged and dished head(Torrisherical Head)
6 in16 constant
1.75 constant For the new condition0.962 in 24.44 mm From the table tm1.087 in 27.62 mm 2SEt/(LM+0.2t) P
Thickness of the plate selected 0.5 inAllowable pressure 153.99 psi
Thickness of the plate selected 0.3125 inAllowable pressure 193.43 psi
Thickness of the plate selected 0.4375 inAllowable pressure 159.49 psi
Thickness of the plate selected 0.5 in
Allowable pressure 133.45 psi
Thickness of the plate selected 0.625 inAllowable pressure 128.48 psi
Thickness of the plate selected 0.625 inAllowable pressure 129.94 psi
Formula in terms of external diameter
Input Req. P Design PressureInput Req. S Allowable Stress Value
Input Req. E
Input Req. E Efficiency of seamless head
Input Req. R
Input Req. D
t Required wall thicknessInput Req. C.A. Corriosion allowance
Cylindrical Shell (Long Seam)
Answer t PR/(SE+0.4P)
Answer t+CA PR/(SE+0.4P)+CA
Sphere and Hemispherical Head
Answer t PR/(2SE+0.8P)
Answer t+CA PR/(2SE+0.8P)+CA
Ellipsoidal Head
Answer t PD/(2SE+1.8P)
Answer t+CA PD/(2SE+1.8P)+CA
Cone and Conical section
Efficiency of spot examined joints of shell and hemis head to shell
outside radius(In corrison condition greater with the corrsion allowance)
outside diameter(In corrison condition greater with the corrsion allowance)
Input Req. alpha One half of the apex angle
Answer t PD/(2cos@(SE+0.4P))
Answer t+CA PD/(2cos@(SE+0.4P))+CA
ASME flanged and dished head(Torrisherical Head)When L/r ratio is equal to 16 2/3
Answer t 0.885PL/(SE+0.8P)
Answer t+CA 0.885PL/(SE+0.8P)+CA
ASME flanged and dished head(Torrisherical Head)When L/r ratio is less than 16
Input Req. r Knuckle radiusAnswer L/r Less thann 16 2/3
From tableM Factor M
Answer t PLM/(2SE+P(M-0.2))
Answer t+CA PLM/(2SE+P(M-0.2))+CA
Formula in terms of external diameter
100 psi17500 psi A 515 gr 70 at 650C
0.85
1
48 inches1219.2 mm
96 inches
2438.4 mminches
0.125 inches 3.175 mm
For the new condition0.322 inches 8.17 mm From the table tm
0.447 inches 11.35 mm SEt/(R-0.4t) P
For the new condition0.161 in 4.09 mm From the table tm
0.286 in 7.26 mm 2SEt/(R-0.8t) P
For the new condition0.273 in 6.93 mm From the table tm
0.398 in 10.11 mm 2SEt/(D-1.8t) P
`30 deg. From the table tm
0.372 in 9.44 mm 2SEtcos@/(D-0.8tcos@) P
0.497 in 12.62 mm
ASME flanged and dished head(Torrisherical Head)
For the new condition0.483 in 12.28 mm From the table tm
0.608 in 15.45 mm SEt/(.885L-0.8t) P
ASME flanged and dished head(Torrisherical Head)
6 in16 constant
1.75 constant For the new condition0.478 in 12.14 mm From the table tm
0.603 in 15.31 mm 2SEt/(LM-t(M-0.2)) P
Thickness of the plate selected 0.5 in
Allowable pressure 155.60 psi
Thickness of the plate selected 0.3125 in
Allowable pressure 194.70 psi
Thickness of the plate selected 0.4375 in
Allowable pressure 160.82 psi
Thickness of the plate selected 0.5 in
Allowable pressure 134.66 psi
Thickness of the plate selected 0.625 in
Allowable pressure 129.50 psi
Thickness of the plate selected 0.625 in
Allowable pressure 130.96 psi
Circular Flat Heads
Input Req PInput Req dInput Req EInput Req S Input Req trInput Req ts
t
From table th
Result
Result
Circular Flat Welded Heads of various types
C
t
From table th
Using thicker plate for the shell reduces the thickness of the head
Input Req ts
C
t
Circular Flat Heads
Design Pressure 300 psiInside diameter of the shell 24 in
Joint Efficiency 1Allowable Stress 15000 psi
Thickness of the shell as calculated 0.243 inThickness of the shell from the available thickness 0.313 in
thickness of the circular flat=d√(0.13P/SE) 1.224 inActual thickness of head exclusive of corrosion allowance 1.25 in
Checks to performedth should not be less than ts Satisfy the check
th/d 0.052 Constantth/d should not be less than 0.05 nor greater than 0.25 Satisfy the Check
Circular Flat Welded Heads of various types
0.33tr/ts 0.257 ConstantChecks to performed
cmin be 0.2 Satisfy the check
d√(CP/SE) 1.719 in
Actual thickness of head exclusive of corrosion allowance 1.75 in
Using thicker plate for the shell reduces the thickness of the head
Thickness of the shell from the available thickness 0.375 in
0.33tr/ts 0.214 Constant
d√(CP/SE) 1.570 in
2√(d*ts) 6
This shell distance shall be maintained at the distance of from the inside face of the head
31.08362 mm
43.67119 mm
39.86616 mm
inches
0.130.1875
0.2
Design for the thickness of the vessel in the case of external pressure
Input Req. PInput Req. DoInput Req. Tan len.
From table E
Input Req. tLL/DoDo/t
From Graph AFrom Graph B
Pa
Result
LL/DoDo/t
From Graph AFrom Graph B
PaResult
Example
Example
Design for the thickness of the vessel in the case of external pressure
External Design Pressure 15 psiOutside diameter of the shell 96 inLength of the vessel from the tan line to tan line 48 ft 576 inHead is ellipsoidal 2:1Material A 285 Gr CModullus of Elasticity 27000000 psi
Determination of the shell thicknessAssume shell thickness of 0.5 inLenghth of the vessel=tan len,+1/3 head len. 592 inRatio 6.17Ratio 192Check the condition(For Do/t=<10) The following formula holds goodFactor from the graph 0.00007Factor from the graph To the left side
6.56 psi
Check the condition Thethickness is not sufficeint and stiffining are to be added
Adding two stiffners in the vessel 2 NosLenghth of the vessel=tan len,+1/3 head len. 200 inRatio 2.08Ratio 192Factor from the graph 0.00022Factor from the graph 3000
Pa=4*B/(3*Do/t) 20.83 psiCheck the condition The thickness is O.K.
To the left side of the graph=2AE/(3*Do/t)
Thethickness is not sufficeint and stiffining are to be added
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