Introduction
This spreadsheet is designed as an aid in performing pressure vessel calculations in accordance with ASME Section VIII, Division 1 Boiler and Pressure Vessel Code. The calculations contained in this p useful for rerating rerating vessel vessels, s, performing performing alterations, alterations, or or for genera generall design design studies. studies. The work work sheets sheets in in t program deal only with the most commonly used portions of the code. The program is not intended t all aspects of the code. Refer to the applicable sections of the code for restrictions. The calculations considerati consideration on only stresse stresses s imposed imposed as a result result of pressure. pressure. Other superimpo superimposed sed loads loads such such as pipi pipi equi equipme pment nt reac reacti tion ons, s, wind wind load loadin ing, g, fluid fluid shoc shock, k, etc. etc. must must be cons consid ider ered ed sepe seperat ratel ely y. Incl Includ udin ing g the the intr intr there are eleven work sheets in the program. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Introduction Shell thickness t for ellipsoidal head t for torispherical head t for hemispherical head t for bolted flat head Material properties External pressure on shells shells Stiffening ring Reinforcement requirement w with ith no added element Reinforcement requirement with with element added
Introduction
the rogram are he include take into g or oduction,
Shell thickness
Minumum shell thickness for vessel under internal pressure: Calculation based on ASME Section VIII, Division 1 paragraph UG-27. Where:
t = minimum required thickness of shell, inches P = internal pressure, psi R = inside radius of shell course under consideration, inches S = maximum allowable stress value, psi. at design temperature. E = joint efficiency. See UW-12 for welded shells. See UG-53 for ligaments between openings.
The minumum thickness will be the greater thickness of t = (PR)/(SE - 0.6P) for circumferential stress or t = (PR)/(2SE + 0.4P) for longitudinal stress. Enter Values: P= R= S= E=
35 psi 172 inches 17500 psi 0.85
Based on circumferential stress, Based on longitudinal stress,
t= t=
NOTE: The value of S is selected from the allowable stress tables an in Section 2D ot the ASME code. Do not use yield or tensile stregnth values as in API 653 calculations. 0.405 inches 0.202 inches
USE
t=
0.405 inches
t for Ellipsoidal Head
Formed vessel heads generally fall into one of three categories: ellipsoidal, torispherical, or hemispherical. Ellipsoidal: Inside depth of the head minus the skirt is equal to one fourth of the inside diameter of the skirt. These are also commonly refered to as 2:1 elliptical heads. Torispherical: Inside crown radius is equal to the outside diameter of the skirt and the knuckle radius is 0.06 times the inside crown radius. It will not be readily apparent in the field whether a head is ellipsoidal or torispherical so it's best to consult vendor drawings and data. The calculations below are for pressure on the concave side.
Thickness calculation for ellipsoidal head. Based on ASME Section VIII, paragraph UG-32(d) t=(PD)/(2SE - 0.2P)
Enter values:
Calculated thickness,
where
t = minimum required thickness of head, inches D = inside diameter of head at skirt, inches P = internal design pressure, psi E = joint efficiency S = maximum allowable stress value, psi
P= D= S= E= t
35 psi 162 inches 13800 psi 1 0.205 inches
t for Torispherical Head
Formed vessel heads will generally fall into one of three categories: ellipsoidal, torispherical, or hemis Ellipsoidal: Inside depth of the head minus the skirt is equal to one fourth of the inside diameter of the These are also commonly refered to as 2:1 elliptical heads. Torispherical: Inside crown radius is equal to the outside diameter of the skirt and the knuckle radius i the inside crown radius. It will not be readily apparent in the field whether a head is ellipsoidal or torispherical so it's best to con drawings and data. The calculations below are for pressure on the concave side.
Thickness calculation for torispherical head. Based on ASME Section VIII, paragraph UG-32(e) t = (.885PL)/(SE-0.1P)
Enter values:
Calculated thickness,
where t = minimum required thickness of head, inches L = inside spherical or crown radius, inches P = internal design pressure, psi E = joint efficiency S = maximum allowable stress value, psi P= L= S= E= t
35 psi 146 inches 13800 psi 1 0.328 inches
t for Torispherical Head
herical. skirt. 0.06 times
sult vendor
t for Hemispherical Head
Formed vessel heads will generally fall into one of three categories: ellipsoidal, torispherical, or hemisp Ellipsoidal: Inside depth of the head minus the skirt is equal to one fourth of the inside diameter of the These are also commonly refered to as 2:1 elliptical heads. Torispherical: Inside crown radius is equal to the outside diameter of the skirt and the knuckle radius is inside crown radius. It will not be readily apparent in the field whether a head is ellipsoidal or torispherical so it's best to cons drawings and data. The calculations below are for pressure on the concave side.
Thickness calculation for hemispherical heads. Based on ASME Section VIII, paragraph UG-32(f) t = (PL)/(2SE-0.2P)
where
Enter values:
P= L= S= E=
Calculated thickness,
t=
t = minimum required thickness of head, inches L = inside spherical or crown r adius, inches P = internal design pressure, psi E = joint efficiency S = maximum allowable stress value, psi 4500 psi 6.8 inches 30000 psi 1 0.518 inches
t is less than 0.365L or P is less than 0.665SE; therefore, code formula is valid.
t for Hemispherical Head
erical. kirt.
0.06 times the
ult vendor
t for Bolted Flat Head
CALCULATION FOR THICKNESS OF BOLTED, FLAT UNSTAYED CIRCULAR HEADS, COVERS, AND BLIND FLANGES Enter values: Bolt circle diameter Nominal bolt size Number of bolts Gasket Factor, Seating stress, Gasket O.D., Gasket I. D., Seal ing Fac e O.D., Sealing Face I.D., Design pressure,
m= y= Go = Gi = Fo = Fi = P=
Allowable bolt stress at ambient temperature, S b =
20000 psi
Allowable stress for head at design temp, S=
17500 psi
Calculated values: Bolt area, single bolt Total bolt area Diameter at location of gasket l oad reaction Width used to determine basic seating width, bo
NOTE:
48.625 inches 0.75 inches 52 3.75 9000 p si 47.375 inches 46.375 inches 47.375 inches 44.5 inches 115 psi
1. This program calculates the m inimum required thickness for bolted, flat unstayed circular heads, covers, and blind flanges of the type shown in Fig. UG-34, sketch (j) and sketch (k) of Part UG-34 in the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1. 2. Enter the decimal equivalent of fractions for all dimensions. 3. Gasket Factor, m, and Seating Stress, y, for a given gasket material are obtained from table 2-5.1 in Appendix 2 of the ASME Code or table UA49.1 in the Lamons Gasket Handbook. 4. The basic gasket seating width, bO, in cell C24 must be selected from table 2-5.2 in Appendix 2 of the ASME Code or table UA-49.2 in the Lamons Gasket Handbook and manually entered at the cell location. 5. All formulas and tables in the Lamons Handbook are taken from Appendix 2 of the ASME Boiler and Pressure Vessel Code, Section Vlll, Division 1.
0.334 in 17.368 in
A= Ab = G=
46.88 inches
N=
0.50 inches
bo =
0.25
b=
0.25
SCROLL DOWN Basic seating width, table 2-5.2, Appedix 2, ASME Sect. VIII Effective gasket seating width, table 25.2, App. 2 ASME Sect VIII Initial bolt load for seating gasket
W m2 = 3.14bGy =
Bolt load required for operating conditions
W m1 =
Head thickness based on operating conditions
Head thickness based on gasket seating Operating conditions govern therefore use t1
331340 l bs.
2
.785G P + 6.28bGmP
t1 =
2.191 inches
t2 =
0.8865659 inches
=
230212 lbs.
2.191 inches
Page 9
Bolt area req'd for seating
Am2 = W m2/Sb =
16.57 in2
Bolt area req'd for operating
Am1 = W m1/Sb =
11.51 in2
Bolt area selected
16.567 in2
Material Properties
MAXIMUM ALLOWABLE STRESS, KSI, FOR META
Nominal Composition
SPEC NO.
C-Mn-Si
SA36
C-Mn
SA53
C-Si
SA106
C
SA179 1
TYPE/ GRADE PRODUCT FORM
MINIMUM -20 to TENSILE, MINUMUM 100 psi YIELD, psi
150
200
250
300
400
500
600
plate, sheet
58,000
36,000
14.5
14.5
14.5 14.5 14.5
14.5
14.5
14.5
S/B
smls. pipe
60,000
35,000
15.0
15.0
15.0 15.0 15.0
15.0
15.0
15.0
B
smls. pipe
60,000
35,000
15.0
15.0
15.0 15.0 15.0
15.0
15.0
15.0
smls. tube
47,000
26,000
11.8
11.8
11.8 11.8 11.8
11.8
11.8
11.8
1Cr- /5 Mo
SA193
B7
bolting (<2.5")
125,000
105,000
25.0
25.0
25.0 25.0 25.0
25.0
25.0
25.0
16Cr-12Ni-2Mo
SA193
B8M2
bolting (<2")
95,000
75,000
18.8
18.8
18.8 18.8 18.8
18.8
18.8
18.8
C
SA214
wld. tube
47,000
26,000
10.0
10.0
10.0 10.0 10.0
10.0
10.0
10.0
C-Si
SA234
WPB
fittings
60,000
35,000
15.0
15.0
15.0 15.0 15.0
15.0
15.0
15.0
18Cr-8Ni
SA240
304
plate
75,000
30,000
18.8
18.8
15.7 15.7 14.1
12.9
12.1
11.4
18Cr-8Ni
SA240
304H
plate
75,000
30,000
18.8
18.8
15.7 15.7 14.1
12.9
12.1
11.4
18Cr-8Ni
SA240
304L
plate
70,000
25,000
16.7
16.7
14.3 14.3 12.8
11.7
10.9
10.3
16Cr-12Ni-2Mo
SA240
316
plate
75,000
30,000
18.8
18.8
17.7 17.7 15.6
14.3
13.3
12.6
16Cr-12Ni-2Mo
SA240
316L
plate
70,000
25,000
16.7
16.7
14.1 14.1 12.7
11.7
10.9
10.4
C
SA283
C
plate
55,000
30,000
13.8
13.8
13.8 13.8 13.8
13.8
13.8
13.8
C
SA285
C
plate
55,000
30,000
13.8
13.8
13.8 13.8 13.8
13.8
13.8
13.8
16.3
14.3 14.3 12.8
11.7
10.9
10.3
18Cr-8Ni
SA312
TP304L
smls. pipe
70,000
25,000
16.3
16Cr-12Ni-2Mo
SA312
TP316L
smls. pipe
70,000
25,000
16.7
16.7
14.1 14.1 12.7
11.7
10.9
10.4
1Cr- /5 Mo
SA320
L7
bolting
125,000
105,000
25.0
25.0
25.0 25.0 25.0
25.0
25.0
25.0
C-Mn-Si
SA333
6
smls. pipe
60,000
35,000
15.0
15.0
15.0 15.0 15.0
15.0
15.0
15.0
smls. pipe
1
1
1
SA335
P11
60,000
30,000
15.0
15.0
15.0 15.0 15.0
15.0
15.0
15.0
1Cr- /2 Mo
SA387
Gr12 Cl2 plate
65,000
40,000
16.3
16.3
16.3 16.3 16.3
16.3
16.3
16.3
C-Si
SA515
70
plate
70,000
38,000
17.5
17.5
17.5 17.5 17.5
17.5
17.5
17.5
C-Si
SA516
55
plate
55,000
30,000
13.8
13.8
13.8 13.8 13.8
13.8
13.8
13.8
C-Mn-Si
SA516
60
plate
60,000
32,000
15.0
15.0
15.0 15.0 15.0
15.0
15.0
15.0
C-Mn-Si
SA516
65
plate
65,000
35,000
16.3
16.3
16.3 16.3 16.3
16.3
16.3
16.3
1 /4 Cr- /2 Mo-Si 1
Material Properties
O
cont'd ==>
TEMP. F ===>
650
700
750
800
850
900
950
1000 1050 1100 1150 1200 1250 1300 1350 1400 1450 1500
15.0
14.4
13.0
10.8
7.8
5
15.0
14.4
13.0
10.8
8.7
6.5
11.8
11.5
10.6
9.2
7.9
6.5
25.0
25.0
23.6
21.0
17.0
12.5
18.8
18.8
18.8
18.8
18.8
18.8 18.8 18.8
10.0
9.8
9.1
7.8
6.7
5.5
3.8
2.1
15.0
14.4
13.0
10.8
8.7
6.6
4.6
2.5
11.2
11.1
10.8
10.6
10.4
10.2 10.0
9.8
9.5
8.9
7.7
6.1
4.7
3.7
2.9.
2.3
1.8
1.4
11.2
11.1
10.8
10.6
10.4
10.2 10.0
9.8
9.5
8.9
7.7
6.1
4.7
3.7
2.9.
2.3
1.8
1.4
10.1
10.0
9.8
9.7
12.3
12.1
11.9
11.7
11.6
11.5 11.4 11.3
11.2
11.0
9.8
7.4
5.5
4.1
3.1
2.3
1.7
1.3
10.2
10.0
9.8
9.6
9.4
13.8
13.3
12.1
10.0
8.4
10.1
10.0
9.8
9.7
10.2
10.0
9.8
9.6
9.4
25.0
25.0
15.0
14.4
13.0
10.8
7.8
15.0
15.0
14.8
14.4
14
16.3
16.3
16.3
16.3
15.8
17.5
16.6
14.8
12.0
13.8
13.3
12.1
15.0
14.4
16.3
15.5
14.5 4.5
2.5
8.5
4.5
13.8 6.5
5
3.0
13.6
1.5
9.3
6.3
4.2
2.8
1.9
1.2
15.2 11.3
7.2
4.5
2.8
1.8
1.1
9.3
6.5
4.5
2.5
10.0
8.4
6.5
4.5
2.5
13.0
10.8
8.7
6.5
4.5
2.5
13.9
11.4
9.0
6.5
4.5
2.5
Ext. Pres. on Shells
Thickness of cylindrical shells under external pressure. ASME Sect. VIII, paragraph UG-28. This work sheet calculates the allowable external pressure for a cylindrical vessel having a known outside diameter, wall thickness, and length between lines of support. It is assumed that external stiffeners are adequately designed. Gather the following information and reference materials prior to using the worksheet. 1. 2. 3. 4. 5.
Material designation for the vessel Design temperature Outside diameter Vessel shell thickness Section ll, Part D of the ASME Code opened to Subpart 3 (page 621)
Step 1. Enter known values. Outside diameter, Do = Shell thickness, t = Section length between lines of support, L=
90 inches 1 inches 920 inches Do / t =
Step 2. Calculate ratios.
Note: For definition of a line of support, see ASME Section VIII, paragraph UG-28(b). 90
L / Do =
10.222
Step 3. Determine factor A a. Go to ASME Section II, Part D, Subpart 3, Figure G (page 622 & 623). b. Enter Figure G at the value of L / Do in Step 2 above. If L / Do is greater than 50, enter the chart at L / Do = 50. If L / Do is less than 0.05, enter the chart at L / Do = 0.05. c. Move horizontally to the line for the value of D o / t calculated above. From this point of intersection, move vertically downward to determine the value of factor A. d. Enter the value for factor A at cell B29 below. (scroll down) Value of factor A =
0.00015
Step 4. Determine factor B a. Using the value of A from step 3, enter the applicable material chart in Section II, Part D, Subpart 3
Stiffening Ring
This worksheet calculates the required moment of inertia for a stiffening ring attached to a cylindrical shell under external pressure. The calculated moment of inertia can be compared to the moment of inertia of a corroded or damaged stiffening ring.The calculation is performed in accordance to ASME Sect. VIII, paragraph UG-29. Information and reference material needed to perform this calculation include: * ASME Section II, Part D, Subpart 3 * modulus of elasticity, E, for stiffening ring material at design temperature * outside diameter of shell * shell thickness * distance between lines of support (see ASME Sect. VIII, paragraph UG-28(b)) * cross sectional area of existing stiffening ring
Step 1. Enter known values. Shell O.D. Do = Shell thickness t= External pressure P= Modulus of elasticity for material E=
169 inches 0.3125 inches 15 psi
2.45E+07 psi
Cross sectional area of stiffener, As = L s =
2
2.39 in 40 inches
Step 2. Factor B calculated B=
5107
L s is defined as one half the distance from the stiffener center line to the next line of support above plus one half the distance from the stiffener center line to the next line of support below. (ASME VIII, UG-29)
reinforcement, no element
Reinforcement requirement for openings in shells without reinforcing elements. Reference ASME Sect. VIII, paragraph UG-37. Calculations in this work sheet are valid only for circular openings in cylindrical shells or formed heads (flat heads excluded). See paragraphs UG-36 through UG-43. Enter values:
0 in.
Inside diameter of vessel, Nominal thickness of shell, t = Nominal thickness of nozzle wall, tn =
16600 psi
Finished diameter of opening, d=
14300 psi
Leg length of outward nozzle weld, li =
Design pressure
250 psi
Design temperature
150
Corrosion allowance Allowable stress for nozzle mat'l Sn = Allowable stress for shell mat'l S v = Correction factor for nozzle orientation, F= required shell thickness tr = Calculated values: strength reduction factor, f r1 = Required nozzle thickness Area available in shell Area available in nozzle projecting outward Area available in nozzle projecting inward A3 =
O
F
60 in.
0.5 in.
Shell joint efficiency Nozzle inserted through shell, y or n Nozzle abutting shell, y or n
11.75 in.
Distance nozzle projects beyond inner wall, h=
0
0.375 in.
Leg length of inward nozzle weld, lo =
0
0.75 in.
1 y n
1 See figure UG-37 for determining the value of F Obtain the required shell or head thickness for cell B12 from calculations performed using the appropriate worksheet in this program.
0.530 in.
strength recuction factor, f r2 =
1.00
Reinforcing area required, A=
0.089 in.
1.00 6.228 in
2
A1 =
2.585
or
A1 =
0.550
Use larger value, A1 =
2.585
A2 =
1.540
or
A2 =
1.03
Use smaller value, A2 =
1.03
0
Area available in outward weld, A41 = Total available area =
Area available in inward nozzle weld, A 43 =
0.141 2
3.752 in Available area is less than area required. Opening is not adequately reinforced. Reinforcing elements must be added or thicknesses must be increased.
Page 14
0.000
reinforcement with element
Reinforcement requirement for openings in shells with reinforcing elements. Reference ASME Sect. VIII, paragraph UG-37. Calculations in this work sheet are valid only for circular openings in straight cylindrical shells and formed heads. See paragraphs UG-36 through UG-43.
Enter values: Design pressure Design temperature Corrosion allowance Allowable stress for nozzle mat'l Sn = Allowable stress for shell mat'l Sv = Allowable stress for element mat'l, Sp = Joint efficiency at opening location, E 1= Correction factor for nozzle orientation, F= Required shell or head thickness, tr =
Inside diameter of vessel, Nominal thickness of shell, t = Nominal thickness of
250 psi
tn =
0.5 in.
Shell joint efficiency, E= Nozzle inserted through shell, y or n Nozzle abutting shell, y or n
16600 psi
Finished diameter of opening, d=
11.75 in.
Distance nozzle projects beyond inner wall, h=
14300 psi
Leg length of outward nozzle weld, l i =
0.250 in.
Leg length of inward nozzle weld, l o =
14300 psi
Thickness or height of element, te =
0.500 in.
Outside diameter or reinforcing element, D p =
700
O
F
nozzle wall,
0 in.
0.85
60 in. 0.75 in.
y n
0 0 18.75
Note: E 1=1 when opening is in solid plate or in Category B butt weld. Use efficiency obtained from Table UW-12 when opening passes through any other weld. Leg length of outer element weld, l e =
1 See figure UG-37 for determining the value of F 0.53
1
0.5
Obtain the required shell or head thickness for cell B14 from calculations performed using the appropriate worksheet in this program.
Calculated values:
Required nozzle thickness
0.089 in.
strength reduction factor, f r1 =
1.00
strength recuction factor, f r 2 =
1.00
strength reduction factor, f r3 =
1.00
strength recuction factor, f r4 =
1.00
Reinforcing area required, A= Area available in shell rea av a a e n nozzle projecting outward Area available in nozzle projecting inward A3 =
A1 =
1.263
A2 =
1.540
0
Area in outer element weld
A42 =
2
6.228 in
or
A1 =
0.269
Use larger value, A 1 =
1.263
or
A2 =
1.438
Use smaller value, A2 =
1.44
Area available in outward nozzle weld, A41 =
Area available in inward nozzle weld, A 43 =
0.063
Area available in 0.25
element,
A5
=
3.000 2
Total available area = 6.013 in Available area is less than area required. Opening is not adequately reinforced. Reinforcing elements must be added or thicknesses must be increased.
Page 15
0.000
