api 650 tank
DESCRIPTION
design excel sheetTRANSCRIPT
SR. NO. DESCRIPTION
1 DESIGN DATA
2 CALCULATIONS FOR MINIMUM SHELL THICKNESS
3 BOTTOM PLATE DESIGN
4 INTERMEDIATE WIND GIRDER
5 VERIFICATION OF UNSTIFFENED SHELL FOR EXTERNAL PRESSURE
6 DESIGN OF ROOF
7 CALCULATION OF ROOF STIFFENER
8 TANK STABILITY AGAINST UPLIFT DUE TO INTERNAL PRESSURE
9 STABILITY OF TANK AGAINST WIND LOADS
9.1 RESISTANCE TO SLIDING
10 SEISMIC CALCULATION
11 ANCHORAGE FOR UPLIFT LOAD CASES
12 ANCHOR CHAIR CALCULATION
13 WEIGHT SUMMARY
14 FOUNDATION LOADING DATA
15 EVALUATION OF EXTERNAL LOADS ON TANK SHELL OPENINGS
AS PER P.3 OF API 650, ADD. 4, 2005
16 VRV AND VENTING CALCULATIONS (PENDING)
17 DESIGN OF LIFTING TRUNNION (PENDING)
CONTENTS:-
1) DESIGN DATA
Design Code API STANDARD 650
TENTH EDITION, NOVEMBER 1998
ADDENDUM 4, DECEMBER 2005
APPENDICES: J, M & S
Flat Roof Design "Process Equipment Design"
By Lloyd E. Brownell & Edwin H. Young
Item No. : TK-66202
Description : EJECTORS HOT WALL
Material : SA 240 TYPE 316
Density of Contents = 980
Specific Gravity of Contents G = 0.980
Material's Yield Strength @ Design Temperature = 166.67 MPa (As Per Table S-5)
Design Temperature = 130
Operating Temperature = 80
Design Internal Pressure = ATM kPa 0
High Liquid Level = 1.600 m (HLL)
Design Liquid Level = 1.900 m (As Per PIPVESTA002)
Allowable Design Stress @ Design Temperature = 148.33 MPa (Table S-2)
Allowable Hydrostatic Stress @ Ambient Temperature = 186.00 MPa (Table S-2)
Corrosion Allowance
Bottom = 0 mm
Shell = 0 mm
Roof = 0 mm
Structure = 0 mm
Slope of Tank Roof q = 0 degree (Flat Roof)
Inside Diameter of Tank = 1.800 m
Outside Diameter of Tank = 1.812 m
D = 1.806 m
Height of Tank H = 1.900 m
Weight of Top Curb Angle = 0.348 kN
Weight of Roof Attachments (Assumed) = 10 kN (Nozzles, Insulation, Railing/Platform)
Weight of Shell Attachments (Assumed) = 14 kN (Nozzles, Insulation, Ladder & Partition Plates)
Design Wind Velocity V = 155 kph
Modulus of Elasticity @ Design Temperature E = 185000 MPa (Table S-6)
Live Load on Roof = 1.20 kPa (PIP VESTA002, 3.2.D)
2) CALCULATIONS FOR MINIMUM SHELL THICKNESS
As per chapter 3, clause 3.6.1.1, the shell thickness for tanks with nominal tank diameter less than 15 m shall
not be less than 5 mm. The required minimum thickness of shell plates shall be the greater of the values computed
by the following formulas (As per Appendix S, clause S.3.2)
Design Shell Thickness =
Hydrostatic Test Thickness =
G = Specific Gravity of Fluid to be Stored = 0.980
D = Nominal Dia. of Tank = 1.806 m
= 1.900 m
CA = Corrosion Allowance = 0 mm
= 148.33 MPa
= 186.00 MPa
E = Weld Joint Efficiency = 0.85 (Table S-4)
Dc kg/m3
Fym
TDSNoC
TOPRoC
Pi
Hl
HL1
Sd
St
Di
Do
Nominal Tank Diameter = Di + Bottom Shell Thickness
Wc
Wra
Wsa
Lr
t d 4.9D (H L1 - 0.3)G + CA
(Sd) (E)
t t 4.9D (H L1 - 0.3)
(St) (E)
td = Design shell thickness, mm
tt = Hydrostatic test shell thickness, mm
HL1 = Design Liquid Level
Sd = Allowable Stress for Design Condition
St = Allowable Stress for Hydrostatic condition
Shell Course
(Including Curb Angle) = 1.900 m
= 1.900 m
Design Shell Thickness = 0.110 mm
Hydrostatic Test Thickness = 0.090 mm
Shell Thickness Provided = 6.00 mm
az
Shell Course 1
Shell Width, m 1.90
Shell Thickness, mm (Uncorroded) 6.00
Shell Thickness, mm (Corroded) 6.00
Shell Weight, kN (Uncorroded) 5.08
Shell Weight, kN (Corroded) 5.08
Total Shell Weight (Uncorroded) = 5.08 kN
Total Shell Weight (including partition plates) (Corroded) = 5.08 kN
Top Curb Angle (Formed Section) L 65 x 65 x 6 Thk.
Cross-sectional Area of the Top Curb Angle = 780
Weight of Top Curb Angle (Uncorroded) = 0.35 kN
Weight of Top Curb Angle (Corroded) = 0.35 kN
3) BOTTOM PLATE DESIGN
As per API 650, Appendix S, Clause S.3.1
All bottom plates shall have minimum nominal thickness of 5 mm, exclusive of any corrosion allowance.
Required Bottom Plate Thickness = 5+ CA mm
= 5 mm
Used Bottom Plate Thickness = 6.00 mm
*Weight of Bottom Plate (Uncorroded) = 137.82 kg = 1.35 kN
*Weight of Bottom Plate (Corroded) = 137.82 kg = 1.35 kN
*Including 50mm Projection Outside of Bottom Shell Course
As per API 650, Appendix J, Clause J.3.2
All bottom plates shall have a minimum nominal thickness of 6 mm.
Required Bottom Plate Thickness = 6 mm
Used Bottom Plate Thickness = 6.00 mm
Weight of Bottom Plate (Uncorroded) = 137.82 kg = 1.35 kN
Weight of Bottom Plate (Corroded) = 137.82 kg = 1.35 kN
Width of course W1
Design Height for Shell Course HL1
td
tt
t1
mm2
tb
tb
tb used
tb
tb used
4) INTERMEDIATE WIND GIRDERS
Maximum Unstiffened Height
As per API 650, Chapter 3, Clause 3.9.7
The maximum height of the unstiffened shell shall be calculated as follows:
As Ordered Thickness of Top Shell Course t = 6.00 mm
Nominal Tank Diameter D = 1.806 m
Design Wind Speed V = 155 kph
Maximum Height of the Unstiffened Shell = 517.01 m
Modification Factor as per S.3.6.7 = Modulus Of Elasticity at Design Temp. = 0.95855
*Maximum Height of the Unstiffened Shell (Modified As Per S.3.6.7) = 495.58 m
Transformed Shell Height
As per API 650, Chapter 3, Clause 3.9.7.2
Transposed width of each shell course
W = Actual Width of Each Shell Course, mm
= 6.00 mm
Shell Course
= 6.00 mm
= 1900 mm
Transformed Height of Tank Shell Htr = 1900 mm
= 1.90 m
[As Htr < H1, Intermediate Wind Girders are not required]
5) VERIFICATION OF UNSTIFFENED SHELL FOR EXTERNAL PRESSURE
Need not to be evaluated as the design external pressure is zero. As per Chapter 3, Clause 3.2.1.i, design external
H1 = 9.47 t (t /D)3/2 (190/V)2
H1
Modulus Of Elasticity at 40oC
H1
Wtr = W x (tuniform/tactual)5/2
tuniform = As Ordered Thickness of top Shell Course, mm
tactual = As Ordered Thickness of Shell Course for Which Transposed Width is Being Calculated (mm)
Thickness of Shell Course t1
Wtr1 = W1 x (ttop/t1)5/2
Wtr1
pressure shall not be less than 0.25 kPa. The tanks designed as per API 650 can sustain this minimum pressure.
6) DESIGN OF ROOF
Roof Plate Thickness Verification for Structurally Stiffened Flat Roof
Methodology:
Consider a strip of roof plate 1 in. wide located at the outer periphery of the
flat roof, and disregard the support offered by the shell. This strip is considered to be essentially
a straight, flat, continuous, uniformly loaded beam, the controlling bending moment is equal to
Over supporting rafters
At midspan
where l = length of beam (strip) between stiffeners, inches, p = unit load, psi.
Introducing the stress resulting from flexure,
f = M / z
For a rectangular beam,
where b = width of beam, inches, and, t = thickness of beam, inches.
For this case, b = 1.0 in.
Ref. "Process Equipment Design" By Lloyd E. Brownell & Edwin H. Young
Chapter 4, Section 4.3 (Roof Design)
Allowable Stresses for Roof Plate Material
Assumed Roof Plate Thickness = 6 mm = 0.23622 in.
Allowable Design Stress @ Design Temperature = 148.33 MPa = 21513 psi [ Table S - 5 ]
Loadings & Critical Combinations
kPa psi lb/in.
Dead Load = 4.40 0.64 0.64
Live Load = 1.20 0.17 0.17
External Pressure = 0.00 0.00 0.00
Internal Pressure = 0.00 0.00 0.00
Load Combination 1 = 5.60 0.81 0.81
Load Combination 2 = 4.40 0.64 0.64
MID ENDS UNIT
Length of beam (strip) between stiffeners l = 25.67 25.67 in.
Load Combination 1 p = 0.812 0.812 lb/in.
Induced Bending Moment M = 22 45 lb-in.
Thickness of the beam (strip) t = 0.236 0.236 in.
Section Modulus z = 0.009 0.009
Allowable Bending Stresses = 21513 21513 psi
Allowable Bending Moment = 200 200 lb-in.
[Satisfactory]
wl2 / 12 and occurs over the supporting stiffeners and wl2 / 24 occurs at the midspan.
Mmax = -wl2 / 12 = -p(1)l2 / 12 = -pl2 / 12
Mmax = -wl2 / 24 = -p(1)l2 / 24 = -pl2 / 24
z = bt2 / 6
Hence, z = t2 / 6
f = pl2 / 2t2
l = t * SQRT ( ( 2 * f ) / p )
t = l / SQRT ( ( 2 * f ) / p )
DL
Lr
Pe
Pi
p = DL + Lr + Pe
p = DL + Pi
Check Adequacy Against Load Combination 1 ( DL + Lr + Pe )
in.3
Fb (Fb = Sd)
Mallow
M < Mallow
l = b
a = Di
MID ENDS UNIT
Length of beam (strip) between stiffeners l = 25.67 25.67 in.
Load Combination 2 p = 0.638 0.638 lb/in.
Induced Bending Moment M = 18 35 lb-in.
Thickness of the beam (strip) t = 0.236 0.236 in.
Section Modulus z = 0.009 0.009
Allowable Bending Stresses = 21513 21513 psi
Allowable Bending Moment = 200 200 lb-in.
[Satisfactory]
Stresses in Roof Plate Segment Between the Stiffeners
Ref. Table 11.4, Formulas for Flat Plates With Straight Boundaries and Constant Thickness
Case no. 8. Rectangular plate, all edges fixed (Uniform loading over entire plate)
(At center)
a / b 1 1.2 1.4 1.6 1.8 2.000 ∞
0.3078 0.3834 0.4356 0.468 0.4872 0.4974 0.500
0.1386 0.1794 0.2094 0.2286 0.2406 0.2472 0.250
α 0.0138 0.0188 0.0226 0.0251 0.0267 0.0277 0.028
a = 1.800 m a = Longer Dimension
b = 0.652 m b = Shorter Dimension
a / b = 2.76
= 0.25 ( See Table Above )
Total Design Load = 5.60 kPa
In Shorter Direction 17 MPa < 148.33 MPa [Satisfactory]
In Longer Direction 126 MPa < 148.33 MPa [Satisfactory]
Total Design Load = 4.40 kPa
In Shorter Direction 13 MPa < 148.33 MPa [Satisfactory]
In Longer Direction 99 MPa < 148.33 MPa [Satisfactory]
Check Adequacy Against Load Combination 2 ( DL + Pi )
in.3
Fb (Fb = Sd)
Mallow
M < Mallow
Smax = ( β2 q b2 ) / t2
β1
β2
β2
Check Plate Stresses Against Load Combination 1 ( DL + Lr + Pe )
(p = q = DL + Lr + Pe)
Smax =
Smax =
Check Adequacy Against Load Combination 2 ( DL + Pi )
(p = q = DL + Lr + Pe)
Smax =
Smax =
7) CALCULATION FOR ROOF STIFFENER
Flange
Breadth 55 mm
Thk. 6 mm
Web
Depth 94 mm
Thk. 6 mmRoof Plate
Reference for Centroid Calculation
Built up Tee Section
Table for Centroid Calculation
Plate A Y AY
1 564 47 26508
2 564 97.0 54708
Σ 1128 81216
Centroid = 72 mm
Table for Moment of Inertia Calculation
b h A
mm mm mm
6 94 415292 564 25.00 352500 767792
55 6 990 330 25.00 206250 207240
Moment of Inertia of Built Up Tee Section = 975032
Section Modulus = 34823
Span of Stiffener a = 1.80 m
Self Weight of Stiffener = 0.16 kN
Weight of Roof Plate Within Stiffined Section = 0.55 kN (Approx.)
Weight of Roof Attachments = 10.00 kN (Nozzles, Insulation, Railing/Platform)
Live Load on Roof = 1.41 kN
Total Design Load Per Unit Length W = 6.73 kN/m
Considering simply supported end conditions for the stiffener,
= 2.7 kN-m
= 27270
[As Zreq'd < Zprov'd, The stiffener design is adequate]
8) TANK STABILITY AGAINST UPLIFT DUE TO INTERNAL PRESSURE
Need not to be evaluated as the design internal pressure is zero in our case.
Ic Yc A x Yc2 I = Ic + A x Yc
2
mm4 mm2 mm4 mm4
mm4
Zprov'd mm3
Mmax W x a2 / 8
Zreq'd mm3 Mmax / (0.6 x Fym)
9) STABILITY OF TANK AGAINST WIND LOAD (ASCE 7-05)
Wind velocity V = 155 kph = 43 m/s
Roof Height Above Shell = 0.04 m Considering 40 mm Thk. Insulation @ Roof
Shell Height H = 1.90 m
Height of Tank Including Roof Height = 1.94 m
Effective Wind Gust Factor G = 0.85 ASCE 7-05,6.5.8.1
Force Co- Efficient = 0.80 By Interpolation (ASCE 7-05, Fig. 6-21)
Wind Directionally Factor = 1.3 600-58H-0010
Velocity Pressure Exposure Co-Eff. = 0.85 ASCE 7-05, Chapter 6, Table 6-3
Topo Graphic Factor = 1
Importance Factor I = 1.15 600-58H-0010
Design Wind Pressure =
1.440 ASCE 7-2005, Chapter 6, Eq. 6-15, Clause 6.5.10
600-58H-0010
Insulation Thickness = 40 mm
Greater of = 2.460 m
(OD + 2 x insulation Thk.) + 0.6 = 2.492 m
= 2.492 m 600-58H-0010
Effective Area Projected = 4.83 600-58H-0010
Design Wind Load P1 = ASCE 7-05, Chapter 6, Eq. 6-28, Clause 6.5.15
= 4.73 kN
Unanchored tanks shall satisfy both of the following conditions:
Case 1:
Case 2:
=
= Pi x A X D / 2
= (Weight of shell + roof + bottom) x D / 2
= 4.6 kN-m = 3387 ft-lbs
= 0 kN-m
= 6.9 kN-m
= 0 For no fluid in the tank
Case 1: 3 < 5 [Satisfactory]
Case 2: 5 < 3 [Unsatisfactory]
[Anchorage against wind pressure is required]
HR
HT
Cf
Kd
Kz
Kzt
qz 0.613 x Kz x Kzt x Kd x V2 x I/1000
kN/m2
Effective Tank Diameter (De)
(OD + 2 x insulation Thk.) x Kd
De
Effective Projected Area (Ae = De x H)
Ae m2
qz x G x Cf x Ae
0.6 Mw + MPi < MDL / 1.5
Mw + 0.4MPi < ( MDL + MF ) / 2
Mw P1 x H / 2
MPi
MDL
Mw
MPi
MDL
MF
9.1) Resistance To Sliding: API 650 3.11.4
The wind load pressure on projected area = 0.86 = 18.0 psf (API 650, Chapter 3, Clause 3.2.1 (f))
Tank OD = 1.812 m
Design Wind Velocity V = 155 kph
Velocity Factor = = 0.666
Wind Pressure on vertical plane surfaces = 0.86 (API 650, Chapter 3, Clause 3.2.1 (f))
Wind Pressure on vertical conical surfaces = 1.44 (API 650, Chapter 3, Clause 3.2.1 (f))
Projected area of roof = 0.036
Projected area of shell = 4.73
=
= 2.74 kN (API 650, Chapter 3, Clause 3.2.1 (f))
= Maximum of 40% of Weight of Tank
= 12.27 kN (API 650, Chapter 3, Clause 3.11.4)
[Anchorage against sliding is not required]
kN/m2
This pressure is for wind velocity of 120 mph (190 kph), for all other wind velocities the pressure shall be adjusted in proportion of ratio (V/190) 2
Do
Vf (V/190)2
kN/m2
kN/m2
m2
m2
Fwind Vf (Wind Pressure on Roof x Projected Area of Roof + Wind Pressure on Shell x Projected Area of Shell)
Ffriction
PENTAGONPENTAGONPENTAGON PENTAGONPENTAGONPENTAGONH/2 for Uniform pressure on Shell
10) Stability Calculations Against Seismic Load (As per API 650 Addendum Four 2005 )
D = 1.806 m Nominal dia of Tank
H = 1.900 m Maximum design product level
D/H = 0.95
H/D = 1.05
Site Class = E
Corroded thickness of bottom plate = 6.00 mm
Corroded thickness of 1st shell course = 6.00 mm
Over turning ring wall moment
= As per API 650 E.6.1.5
For Site class 'E' As per API 650 E.4.9.1
Ai = As per Equation E-4
Acceleration-based site coefficient Fa = 2.5 From Table E-1
Scaling Factor Q = 1 As per API 650 E.4.9.1
= 0.1
= 0.04
= 0.4 X Ss As per E.4.2.c
= 0.04
Rwi = 4 From Table E-4
I = 1.25 600-58H-0010
Ai = 0.08 As per Equation E-4
As per Equation E-6, For seismic design categories E & F,
Ai ≥ As per Equation E-6
≥ 0.006
Condition staisfied= Effective impulse weight of the liquid
When D/H <1.33
= (1-0.218D/H)Wp As per Equation E-14
Wp = Weight of content based on design specific gravity of the product
= 46.48 KN
= 46482 N
= 36.85 KN
= 36850 N
When D/H < 1.33 As per E-6.1.2.1
= Height from the bottom of the shell to the center of action of the lateral Siesmic force
related to impulsive liquid force
= (0.5-0.094D/H)H As per Equation E-17
= 0.78 m
Ws = Total Weight of Shell and appurtenances (Uncorroded)
= 30 KN
Xs = Height from the bottom of the tank shell to center of gravity
= 1.28 m
Wr = Total Weight of fixed tank roof including framing (Uncorroded)
= 0.00 KN
Xr = Height from the top of the shell to the roof and roof appurtenances center of gravity
= 0.00 m
Tc = Natural peroid of the convective (sloshing ) mode of behaviour of the liquid, seconds As per E 4.8.2
Tc = 1.8 x Ks x sqrt (D) As per Equation E-2a
Ks = Sloshing peroid cofficient
Ks = 0.578 As per Equation E-3sqrt (tanh (3.68H/D))
= 0.58
tb
ts
Mrw sqrt{[Ai(WiXi+WsXs+WrXr)]2 + [Ac(WcXc)]2}
2.5 x Q x Fa x So ( I / Rwi )
Ss
S1
So
0.5S1(I/Rwi)
Wi
Wi
Wi
Xi
Xi
Therefore
Tc = 1.40 As per E.4.8.2
= 4 As per E.4.9.1
As per E.4.9.1
Ac = As per Equation E-7
Where
Ts = As per API 650 E-2
= 0.04
Fv = 3.5 From Table E-2
= 2 From Table E-4
Ts = 0.56
Ac = 0.06
Wc = Effective Convective (sloshing)portion of the liquid Weight
= 0.23 x (D/H) Tanh (3.67 H/D) x Wp As per Equation E-15
= 10.15 KN
= 10153 N
Xc = Height from the bottom of the tank shell to the center of action of lateral siemic force related
to convective liquid force
= [1-{Cosh((3.67 x H/D)-1)/((3.67 x H/D) Sinh((3.67 x H/D))}] x H As per Equation E-18
= 1.70 m
Therefore Ring Wall Moment
= 5.40 KN-m
= 5404 N-m = 3985 ft-lbs
Anchorage Ratio J = Mrw As per API 650 E.6.2.1.1.1
Where Av = As per API 650 E.6.1.3
= 2.5 x Q x Fa x So From Equation E-4
= 0.3
Av = 0.035
= 99 x ta x (Fy x H x Ge)^0.5 ≤ 1.28 x H x D x Ge As per API 650 E.6.2.1.1
Where
Ge = Effective specific gravity including vertical seismic effects
= G x (1-0.4 x Av) As per API 650 E-2
= 0.97
ta = Corroded thickness of the bott. plate under the shell extending at the distance L from the inside of the shell
ta = 6.00 mm
= 10391 N/m ≤ 4.2 N/m
= 4.2 N/m
0.004 KN/m
= As per API 650 E.6.2.1.1
= Roof load acting on the tank shell (Uncorroded)
= 0.000 KN/m
= 0 N/m
= 5.37 KN/m
Therefore = 5373 N/m
Anchorage Ratio J = 0.312 < 1.54
Condition staisfied Tank is self anchoredAs Anchors Are Being Provided, The Tank Will Be Considered As Mechanically Anchored
TL
When TC < TL
2.5 x Q x Fa x So x (Ts /Tc) x (I/Rwc) ≤ Ai
(FvS1) / (FaSs)
S1
Rwc
Mrw
Resisting force to be adequate for tank stability J<1.54
D2(wt(1-0.4Av)+wa)
0.14 x SDS
SDS
wa
wa
wa
wa
wt [(Ws/πD)+wrs)]
wrs
wt
10.1) Shell Compression In Mechanically Anchored Tanks As per API 650 E.6.2.2.2
= 1.26 Mpa
10.2) Allowable Longitudinal Membrane Compression Stress in Tank Shell As per API 650 E.6.2.2.3
Calculating value of
= 0.17
= {(83x ts)/(2.5 x D)} + 7.5 x sqrt(G x H) < 0.5 x Fty
Where
G X H = 1.862
= 83.335
Therefore,
= 121 Mpa
As ơc < Fc Condition staisfied
10.3) Seismic Base Shear (As Per E.6.1)
V = Total Design Base Shear (N)
= Design Base Shear Due to Impulsive Component (N)
= Design Base Shear Due to Convective Component (N)
=
= 5260.44 N
=
= 635.113 N
V =
V = 5298.65 N
V = 5.29865 kN
G x H x D2
t2
When GHD2 / t2 is less than 44, then
Fc
0.5 X Fty
Fc
Vi
Vc
Vi Ai(Ws+Wr+Wf+Wi)
Vi
Vc AcWc
Vc
Sqrt(Vi2 + Vc
2)
11) ANCHORAGE FOR UPLIFT LOAD CASES, PER API 650 TABLE 3-21B
P = ATM kPa
= 0.00 in. of water
Test Pressure = 0.00 kPa
= 0.00 in. of water
Dead Load of Shell Minus Any CA and Any Dead Load Other Than Roof
= Weight of shell (Corroded)
= 5424.58 N
= 1219.5 lbs
Dead Load of Shell Minus Any CA and Any Dead Load Including Roof Plate
Acting on the Shell Minus Any CA
= Weight of shell (Corroded) + Weight of Roof (corroded)
= 6807.7 N
= 1530.43 lbs
Dead Load of the Shell Using As Built Thicknesses and Any Dead Load Other Than
Roof Plate Acting on the Shell Using As Built Thickness
= Weight of Shell
= 5424.6 N
= 1219.5 lbs
Yield stress for Anchor Bolts
= 36000 psi SA 307 Gr. B
= 6 mm = 0.2362205 in.
D = 1.806 m = 5.92 ft
= 5.404 kN-m = 3985 ft-lbs (From Seismic Calculation)
Table 3 - 21
UPLIFT LOAD CASES
Design Pressure -1490.05 15076
Test Pressure -1490.05 15076
Wind Load 756.36 15076
Seismic Load 1160.79 15076
Design Pressure +Seismic 1201.17 15076
Design Pressure + Wind 796.74 15076
UPLIFT LOAD CASES
lbs U = Net Uplift Load
Design Pressure -373 -0.025 -15.94 N = No. of Anchor Bolts
Test Pressure -373 -0.025 -15.94
Wind Load 189 0.013 8.09
Seismic Load 290 0.019 12.42
Design Pressure + Seismic 300 0.020 12.85
Design Pressure + Wind 199 0.013 8.52
Pt
W1
W2
W3
Fy
th
MS
NET UPLIFT FORMULA, U (lbf)
*Fy For Anchor Bolts(PSI)
((P - 8th) x D2 x 4.08) - W1
((Pt - 8th) x D2 x 4.08) - W1
(4 x Mw / D) - W2
(4x Ms/D) -W2
((P-8th) x D² x 4.08) + (4 x Ms/D)-W1
((P-8th) x D² x 4.08) + (4 x Mw/D)-W1
tb = U / N Ar = tb/Fall
in.2 mm2
Ar = Required Bolt Area
As per API 650, Chapter 3, Clause 3.1.1.3
Design Tension Load Per Anchor =
Bolt Circle Diameter (BCD) d = 2.000 m
No. of Anchor Bolts N = 4 Nos.
Weight of shell plus roof supported by the shell less 0.4 times the force due to internal pressure W = 6 kNDesign Tension Load Per Anchor = 200 lbs
Required Bolt Area = 13
Provided Bolt Area Consider M30 Bolt = 539 (Uncorroded Root Area)
= 443 (Corroded Root Area)
[Area of the anchor bolt provided is sufficient]
12) ANCHOR CHAIR CALCULATIONS
As Per AISI E-l, Volume ll, Part Vll
Top Plate Thickness Calculations:
Top Plate Thickness
C = Top Plate Thickness
S = Stress At Point = 25 ksi (AISI E-1)
f = Distance From Outside of = 0.98 in.
Top Plate to Edge Of Hole
g = Distance between Gusset Plates = 3.94 in.
d = Anchor Bolt Diameter (corroded) = 1.06 in.
P Design Load or Max. Allowable
= Anchor Bolt Load or 1.5 Times = 0.45 kips
Actual Bolt Load, whichever is
lesser
. Top Plate Thickness Calculated C = 0.151 in. = 3.8 mm
Used Top Plate Thickness C = 0.551 in. = 14 mm
[Top Plate Thickness Is Adequate]
4MW/dN - W/N
Areq. mm2
Aprov. mm2
mm2
C = [P(0.375g-0.22d)/Sf]0.5
P
Jmin g
a
Ød
f
eCh
Anchor Chair Height Calculations:
=
Z = Reduction Factor =
a = Top Plate Width = 6.00 in.
h = Anchor Chair Height = 6.00 in.
R = Nominal Shell Radius = 35.55 in.
t = Shell Thickness (including repad) = 0.472 in.
m = Bottom Plate Thickness = 0.236 in.
e = Anchor Bolt Eccentricity = 3.74 in.
= Allowable Stress = 21.51 ksi
Z = 0.98493
= 0.409 ksi
[Anchor Chair Height Is Adequate]
Gusset Plate Thickness Calculations: 0.04 ( h - C ) or 1/2"
Gusset Plate Thickness = 0.218 in. = 5.5 mm
Gusset Plate Thickness Provided = 14 mm = 0.551 in.
[Gusset Plate Thickness Is Adequate]
13) WEIGHT SUMMARY
Empty = 3282 kg
Weight of Working Fluid = 3990 kg
Operating Weight = 7272 kg (Considering HLL = 1600mm)
Weight of Test Fluid = 4835 kg
Test Weight (Full of water) = 8117 kg
Sind. (Pe/t2)[{1.32*Z/(1.43*a*h2/Rt)+(4ah2)0.333}+{0.031/(Rt)0.5}]
1/[{.177am(m/t)2/(Rt)0.5}+1]
Sall.
Sind.
Jmin
FOUNDATION LOADING DATA
The self weight of roof and live load will be transferred to tank shell
Live load transferred to foundation
Live Load on roof = 1.20
Area of Roof = 2.60
Total Live Load = 3.12 kN
Circumference of Tank C = π x D = 5.69 m
Live Load transferred to Foundation = 0.55 kN/m
Dead load transferred to foundation
Self Weight of Roof + Stiffeners = 1.38 kN
Self Weight of Bottom Plate = 1.35 kN
Self Weight of Shell = 5.42 kN
Self Weight of shell Attachments = 24.02 kN
Total Dead Load acting on shell = 30.83 kN
Dead Load Transferred to Foundation = 5.42 kN/m
Operating & Hydrostatic Test Loads
Self Weight of Tank 32.18 kN = 3282 kgs
Weight of Fluid in Tank at Operating Conditions 39.13 kN = 3990 kgs
Weight of Water in Tank at Hydrotest Conditions 47.41 kN = 4835 kgs
Uniform Load Operating Condition = (Self wt.+ Fluid)/Area 28.02
Uniform Load Hydrotest Condition = (Self wt.+ Water)/Area 31.07
Wind Load Transferred to Foundation
Base Shear due to wind load Fw = 4.73 kN
Reaction due to wind load Rw = 0.45 kN/m
Moment due to wind load Mw = 4.59 kN-m
Seismic Load Transferred to Foundation
Reaction due to seismic load Rs = 0.52 kN/m
Moment due to seismic load Ms = 5.40 kN-m
Base Shear due to seismic load = 5.30 kN
14)
Lr kN/m2
Ar m2
WL = Lr x Ar
LL = WL / C
Wr
Wb
Ws
Wa
Wr + Ws + Wa
Wd = DL
Wr + Ws + Wa + Wb =
Wf =
Ww =
Wo = kN/m2
Wh = kN/m2
FS
Summary of Foundation Loading Data
Dead load, shell, roof & ext. structure loads 5.42 kN/m
Live load 0.55 kN/m
Uniform load, operating condition 28.02
Uniform load, hydrotest load 31.07
Base shear due to seismic 5.30 kN
Reaction due to seismic load Rs = 0.52 kN/m
Moment due to seismic load Ms = 5.40 kN-m
Base shear due to wind 4.73 kN
Reaction due to wind 0.45 kN/m
Moment due to wind load 4.59 kN-m
Note : Consider 15-20% variation in weight while designing the foundation
DL =
LL =
Wo = kN/m2
Wh= kN/m2
FS=
Fw =
Rw =
Mw=
AS THE TOTAL HIGHT OF THE STORAGE TANK IS 12 M WE DIVIDED THIS TANK INTO 6 COURSES OF WIDTH OF 2000 mm EACH
CALCULATIONS OF THE SHELL THICKNESS FOR COURSE 1
As per chapter 3, clause 3.6.1.1, the shell thickness for tanks with nominal tank diameter less than 15 m shall not be less than 5 mm. The required minimum thickness of shell plates shall be the greater of the values computed by the following formulas (As per Appendix S, clause S.3.2)
Design Shell Thickness =
Hydrostatic Test Thickness =
6.515851 mm
4.84512 mmG = Specific Gravity of Fluid to be Stored = 1
D = Nominal Dia. of Tank = 14.008 m
= 12 mCA = Corrosion Allowance = 0 mm
= 145 MPa
= 195 MPaE = Weld Joint Efficiency = 0.85 Table S4
0.85
Width of course (including curb angle) = 2 m
Design Height for Shell Course = 12 m
Design Shell Thickness = 6.515851 mm
Hydrostatic Test Thickness = 4.84512 mm
The designed thickness of the course = 8 mm
Shell Plates Weight SummaryShell Course 1Shell Width, m 2.00Shell Thickness, mm (Uncorroded) 8.00Shell Thickness, mm (Corroded) 8.00Shell Weight, kN (Uncorroded) 2.75Shell Weight, kN (Corroded) 2.75Shell Internal Diameter m Di 14Shell External Diameter m Do 14.016Mean Diamter of the Shell course m D 14.008
t d 4.9D (H L1 - 0.3)G + CA
(Sd) (E)
t t 4.9D (H L1 - 0.3)
(St) (E)td = Design shell thickness, mm
tt = Hydrostatic test shell thickness, mm
HL1 = Design Liquid Level
Sd = Allowable Stress for Design Condition
St = Allowable Stress for Hydrostatic condition
W1
HL1
td
tt
CALCULATIONS OF THE SHELL THICKNESS FOR COURSE 2
As per chapter 3, clause 3.6.1.1, the shell thickness for tanks with nominal tank diameter less than 15 m shall not be less than 5 mm. The required minimum thickness of shell plates shall be the greater of the values computed by the following formulas (As per Appendix S, clause S.3.2)
Design Shell Thickness =
Hydrostatic Test Thickness =
5.398945 mm
4.0146 mmG = Specific Gravity of Fluid to be Stored = 1
D = Nominal Dia. of Tank = 14 m
= 10 mCA = Corrosion Allowance = 0 mm
= 145 MPa
= 195 MPaE = Weld Joint Efficiency = 0.85 Table S4
0.85
Width of course (including curb angle) = 2 m
Design Height for Shell Course = 10 m
Design Shell Thickness = 5.398945 mm
Hydrostatic Test Thickness = 4.0146 mm
c mShell External Diameter m
The designed thickness of the course 1 = 6 mm
Shell Plates Weight SummaryShell Course 1Shell Width, m 2.00Shell Thickness, mm (Uncorroded) 0.00Shell Thickness, mm (Corroded) 0.00Shell Weight, kN (Uncorroded) 0.00Shell Weight, kN (Corroded) 0.00Shell Internal Diameter m Di 14Shell External Diameter m Do 14.012Mean Diamter of the Shell course m D 14.006
t d 4.9D (H L1 - 0.3)G + CA (Sd) (E)
t t 4.9D (H L1 - 0.3) (St) (E)
td = Design shell thickness, mm
tt = Hydrostatic test shell thickness, mm
HL1 = Design Liquid Level
Sd = Allowable Stress for Design Condition
St = Allowable Stress for Hydrostatic condition
W1
HL1
td
tt
CALCULATIONS OF THE SHELL THICKNESS FOR COURSE 3
As per chapter 3, clause 3.6.1.1, the shell thickness for tanks with nominal tank diameter less than 15 m shall not be less than 5 mm. The required minimum thickness of shell plates shall be the greater of the values computed by the following formulas (As per Appendix S, clause S.3.2)
Design Shell Thickness =
Hydrostatic Test Thickness =
4.285761 mm
3.186848 mmG = Specific Gravity of Fluid to be Stored = 1
D = Nominal Dia. of Tank = 14 m
= 8 mCA = Corrosion Allowance = 0 mm
= 145 MPa
= 195 MPaE = Weld Joint Efficiency = 0.85 Table S4
0.85
Width of course (including curb angle) = 2 m
Design Height for Shell Course = 8 m
Design Shell Thickness = 4.285761 mm
Hydrostatic Test Thickness = 3.186848 mm
c mShell External Diameter m
The designed thickness of the course 3
Shell Plates Weight SummaryShell Course 1Shell Width, m 2.00Shell Thickness, mm (Uncorroded) 0.00Shell Thickness, mm (Corroded) 0.00Shell Weight, kN (Uncorroded) 0.00Shell Weight, kN (Corroded) 0.00Shell Internal Diameter m Di 14Shell External Diameter m Do 14.012Mean Diamter of the Shell course m D 14.006
t d 4.9D (H L1 - 0.3)G + CA (Sd) (E)
t t 4.9D (H L1 - 0.3) (St) (E)
td = Design shell thickness, mm
tt = Hydrostatic test shell thickness, mm
HL1 = Design Liquid Level
Sd = Allowable Stress for Design Condition
St = Allowable Stress for Hydrostatic condition
W1
HL1
td
tt
AS THE TOTAL HIGHT OF THE STORAGE TANK IS 12 M WE DIVIDED THIS TANK INTO 6 COURSES OF WIDTH OF 2000 mm EACH
CALCULATIONS OF THE SHELL THICKNESS FOR COURSE 4
As per chapter 3, clause 3.6.1.1, the shell thickness for tanks with nominal tank diameter less than 15 m shall not be less than 5 mm. The required minimum thickness of shell plates shall be the greater of the values computed by the following formulas (As per Appendix S, clause S.3.2)
Design Shell Thickness =
Hydrostatic Test Thickness =
2.659096 mm
2.359095 mmG = Specific Gravity of Fluid to be Stored = 1
D = Nominal Dia. of Tank = 14 m
= 6 mCA = Corrosion Allowance = 0 mm
= 173 MPa
= 195 MPaE = Weld Joint Efficiency = 0.85 Table S4
0.85
Width of course (including curb angle) = 2 m
Design Height for Shell Course = 6 m
Design Shell Thickness = 2.659096 mm
Hydrostatic Test Thickness = 2.359095 mm
The designed thickness of the course
Shell Plates Weight SummaryShell Course 1Shell Width, m 2.00Shell Thickness, mm (Uncorroded) 0.00Shell Thickness, mm (Corroded) 0.00Shell Weight, kN (Uncorroded) 0.00Shell Weight, kN (Corroded) 0.00Shell Internal Diameter m Di 14Shell External Diameter m Do 14.012Mean Diamter of the Shell course m D 14.006
t d 4.9D (H L1 - 0.3)G + CA (Sd) (E)
t t 4.9D (H L1 - 0.3) (St) (E)
td = Design shell thickness, mm
tt = Hydrostatic test shell thickness, mm
HL1 = Design Liquid Level
Sd = Allowable Stress for Design Condition
St = Allowable Stress for Hydrostatic condition
W1
HL1
td
tt
AS THE TOTAL HIGHT OF THE STORAGE TANK IS 12 M WE DIVIDED THIS TANK INTO 6 COURSES OF WIDTH OF 2000 mm EACH
CALCULATIONS OF THE SHELL THICKNESS FOR COURSE 5
As per chapter 3, clause 3.6.1.1, the shell thickness for tanks with nominal tank diameter less than 15 m shall not be less than 5 mm. The required minimum thickness of shell plates shall be the greater of the values computed by the following formulas (As per Appendix S, clause S.3.2)
Design Shell Thickness =
Hydrostatic Test Thickness =
1.72608 mm
1.531342 mmG = Specific Gravity of Fluid to be Stored = 1
D = Nominal Dia. of Tank = 14 m
= 4 mCA = Corrosion Allowance = 0 mm
= 173 MPa
= 195 MPaE = Weld Joint Efficiency = 0.85 Table S4
0.85
Width of course (including curb angle) = 2 m
Design Height for Shell Course = 4 m
Design Shell Thickness = 1.72608 mm
Hydrostatic Test Thickness = 1.531342 mm
The designed thickness of the course
Shell Plates Weight SummaryShell Course 1Shell Width, m 2.00Shell Thickness, mm (Uncorroded) 0.00Shell Thickness, mm (Corroded) 0.00Shell Weight, kN (Uncorroded) 0.00Shell Weight, kN (Corroded) 0.00Shell Internal Diameter m Di 14Shell External Diameter m Do 14.012Mean Diamter of the Shell course m D 14.006
t d 4.9D (H L1 - 0.3)G + CA (Sd) (E)
t t 4.9D (H L1 - 0.3) (St) (E)
td = Design shell thickness, mm
tt = Hydrostatic test shell thickness, mm
HL1 = Design Liquid Level
Sd = Allowable Stress for Design Condition
St = Allowable Stress for Hydrostatic condition
W1
HL1
td
tt
AS THE TOTAL HIGHT OF THE STORAGE TANK IS 12 M WE DIVIDED THIS TANK INTO 6 COURSES OF WIDTH OF 2000 mm EACH
CALCULATIONS OF THE SHELL THICKNESS FOR COURSE 6
As per chapter 3, clause 3.6.1.1, the shell thickness for tanks with nominal tank diameter less than 15 m shall not be less than 5 mm. The required minimum thickness of shell plates shall be the greater of the values computed by the following formulas (As per Appendix S, clause S.3.2)
Design Shell Thickness =
Hydrostatic Test Thickness =
0.793064 mm
0.70359 mmG = Specific Gravity of Fluid to be Stored = 1
D = Nominal Dia. of Tank = 14 m
= 2 mCA = Corrosion Allowance = 0 mm
= 173 MPa
= 195 MPaE = Weld Joint Efficiency = 0.85 Table S4
0.85
Width of course (including curb angle) = 2 m
Design Height for Shell Course = 2 m
Design Shell Thickness = 0.793064 mm
Hydrostatic Test Thickness = 0.70359 mm
The designed thickness of the course
Shell Plates Weight SummaryShell Course 1Shell Width, m 2.00Shell Thickness, mm (Uncorroded) 0.00Shell Thickness, mm (Corroded) 0.00Shell Weight, kN (Uncorroded) 0.00Shell Weight, kN (Corroded) 0.00Shell Internal Diameter m Di 14Shell External Diameter m Do 14.012Mean Diamter of the Shell course m D 14.006
t d 4.9D (H L1 - 0.3)G + CA (Sd) (E)
t t 4.9D (H L1 - 0.3) (St) (E)
td = Design shell thickness, mm
tt = Hydrostatic test shell thickness, mm
HL1 = Design Liquid Level
Sd = Allowable Stress for Design Condition
St = Allowable Stress for Hydrostatic condition
W1
HL1
td
tt
BOTTOM PLATE DESIGN
ACCORDING TO THE API 650 CLAUSE 5.4.1 ALL BOTTOM PLATES SHALL HAVE NOMINAL MINIMUM THICKNESS OF 6 MM (0.236 INCH) EXCLUSIVE OF ANY CORROSION ALLOWANCE AND SHELL HAVE MINIMUM NOMIAL WIDTH OF 1800 MM.
TOP WIND GIRDER ACCORDING TO API 650 CLAUSE 5.9.6.1 THE REQUIRED SECTION MODULUS OF STIFFENING RING SHALL BE DETERMINED BY THE FOLLOWING EQUATION
WHERE Z= REQUIRED MINIMUM SECTION MODULUSD= NOMINAL TANK DIAMETER = 14.008 METERSH2 HIGHT OF THE TANK = 12 METERSV= DESIGN SPEED OF THE WIND (3-SEC GUST)
165 KM/HOUR
Z = 104.4589
INTERMEDIATE WIND GIRDERSaccording to clause 5.9.7.1 of API 650, the maximum hight of the unstiffened shel shall be calculated as follows:
as
WHEREH1= VERTICAL DISTANCE IN M, BETWEEN THE INTERMEDIATE WIND GIRDER AND TOP ANLE OF THE SHELL (meters)
H1 = 21.12045 mt = AS ORDERED THICKNESS UNLESS OR OTHER WISE SPECIFIED OF THE THINNEST SHELL COURSE(mm)
t = 6 mmD = NOMINAL SHELL DIAMETER (m) = 14.008 mV = DESIGN WIND SPEED (3- sec - gust) = 165 km/hr
H1 = 21.12045 meters
TRANSFORMED SHELL
acoording to the clause no: 5.9.7.2 after calculating the maximum hight of the unstiffened shellH1 is detrmined the hight of the transformed shell has to be determined accorging to the following method:
(A)with the following equation change the actual width with each of the shell course into transposedwidth of eachshell course having the top shell thickness
Wtr = W((tuniform)/(t actual))^(5/2)where Wtr = transposed width of the the each shell course (mm) = mmW = actual width of th shell course (mm) = mmt uniform = as ordered thickness of the thinest shell course (mm) = mmt actual = as ordered thickness of the shell course for which transposed width has to be calculated
= mm
Z=(D² H2/17)* (V/190)²
cmᵌ
cmᵌ
H1 = 9.47 * t * ((t/D)ᵌ)^0.5 * (190/V)²
For course 1 having thickness 8 mm recommended
Wtr = W((tuniform)/(t actual))^(5/2)
Wtr = 974.2786 mmW = 2000 mmt uniform = 6 mmt actual = 8 mm
all courses from 2 to 6 having thickness of 6 mm recommended
Wtr = 2000 mmW = 2000 mmt uniform = 6 mmt actual = 6 mm
b. Add the transposed widths of the courses. The sum of the transposed widths of the courses widths of the courses will give the hight of the transpormed shell H transfmd = 10974.28 mm
10.97428 metersas the transformed hight is smaller than the hight of the unstiffened shell there is no need to have a stiffner ring or intermediate wind girder is not required
TANK CONICAL ROOF