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CONTENTS:-SR. NO. DESCRIPTION

DESIGN DATA

CALCULATIONS FOR MINIMUM SHELL THICKNESS

BOTTOM PLATE DESIGN

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)

1

2

3

(2)

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 Dc = 980 kg/m3

Specific Gravity of Contents G = 0.980

Material's Yield Strength @ Design Temperature Fym = 166.67 MPa (As Per Table S-5)

Design Temperature TDSN = 130 oC

Operating Temperature TOPR = 80 oC

Design Internal Pressure Pi = ATM kPa 0

High Liquid Level Hl = 1.600 m (HLL)

Design Liquid Level HL1 = 1.900 m (As Per PIPVESTA002) Allowable Design Stress @ Design Temperature Sd = 148.33 MPa (Table S-2) Allowable Hydrostatic Stress @ Ambient Temperature St = 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 Di = 1.800 m

Outside Diameter of Tank Do = 1.812 m

Nominal Tank Diameter = Di + Bottom Shell Thickness D = 1.806 m

Height of Tank H = 1.900 m

Weight of Top Curb Angle Wc = 0.348 kN Weight of Roof Attachments (Assumed) Wra = 10 kN Weight of Shell Attachments (Assumed) Wsa = 14 kN

Design Wind Velocity V = 155 kph

Modulus of Elasticity @ Design Temperature E = 185000 MPa (Table S-6)

Live Load on Roof Lr = 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)

t d = 4.9D (HL1 - 0.3)G + CA

t t = 4.9D (HL1 - 0.3)

td = Design shell thickness, mm tt = Hydrostatic test shell thickness, mm

G = Specific Gravity of Fluid to be Stored = 0.980 D = Nominal Dia. of Tank = 1.806 m HL1 = Design Liquid Level = 1.900 m

CA = Corrosion Allowance = 0 mm

Sd = Allowable Stress for Design Condition = 148.33 MPa St = Allowable Stress for Hydrostatic condition = 186.00 MPa E = Weld Joint Efficiency = 0.85 (Table S-4)

(St) (E) (Sd) (E) Design Shell Thickness

Hydrostatic Test Thickness

(Nozzles, Insulation, Ladder & Partition Plates) (Nozzles, Insulation, Railing/Platform)

(3)

Shell Course

Width of course (Including Curb Angle) W1 = 1.900 m

Design Height for Shell Course HL1 = 1.900 m

Design Shell Thickness td = 0.110 mm

Hydrostatic Test Thickness tt = 0.090 mm

Shell Thickness Provided t1 = 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 mm2

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 tb = 5+ CA mm

tb = 5 mm

Used Bottom Plate Thickness tb used = 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 tb = 6 mm

Used Bottom Plate Thickness tb used = 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

(4)

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:

H1 = 9.47 t (t /D) 3/2

(190/V)2

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 H1 = 517.01 m

Modification Factor as per S.3.6.7 = Modulus Of Elasticity at Design Temp. = 0.9585 Modulus Of Elasticity at 40oC

*Maximum Height of the Unstiffened Shell (Modified As Per S.3.6.7) H1 = 495.58 m

Transformed Shell Height

As per API 650, Chapter 3, Clause 3.9.7.2

Transposed width of each shell course

Wtr = W x (tuniform/tactual) 5/2

W = Actual Width of Each Shell Course, mm

tuniform = As Ordered Thickness of top Shell Course, mm = 6.00 mm tactual = As Ordered Thickness of Shell Course for Which Transposed Width is Being Calculated (mm)

Shell Course

Thickness of Shell Course t1 = 6.00 mm

Wtr1 = W1 x (ttop/t1) 5/2

Wtr1 = 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 pressure shall not be less than 0.25 kPa. The tanks designed as per API 650 can sustain this minimum pressure.

(5)

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 wl2 / 12 and occurs over the supporting stiffeners and wl2 / 24 occurs at the midspan.

Mmax = -w l 2

/ 12 = -p(1) l2 / 12 = -p l2 / 12 Over supporting rafters

Mmax = -w l 2

/ 24 = -p(1) l2

/ 24 = -p l2

/ 24 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, z = bt2

/ 6

where b = width of beam, inches, and, t = thickness of beam, inches. For this case, b = 1.0 in.

Hence, z = t2 / 6 f = p l2 / 2t2

l = t * SQRT ( ( 2 * f ) / p ) t = l / SQRT ( ( 2 * f ) / p )

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 = 0.2362 in.

Allowable Design Stress @ Design Temperature = 148.33 MPa = 21513 psi [ Table S - 5 ]

Loadings & Critical Combinations

kPa psi lb/in.

Dead Load DL = 4.40 0.64 0.64 Live Load Lr = 1.20 0.17 0.17 External Pressure Pe = 0.00 0.00 0.00 Internal Pressure Pi = 0.00 0.00 0.00 Load Combination 1 p = DL + Lr + Pe = 5.60 0.81 0.81 Load Combination 2 p = DL + Pi = 4.40 0.64 0.64

Check Adequacy Against Load Combination 1 ( DL + Lr + Pe )

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 in.3

Allowable Bending Stresses Fb = 21513 21513 psi (Fb = Sd) Allowable Bending Moment Mallow = 200 200 lb-in.

M < Mallow [Satisfactory]

l = b

(6)

Check Adequacy Against Load Combination 2 ( DL + Pi )

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 in.3

Allowable Bending Stresses Fb = 21513 21513 psi (Fb = Sd) Allowable Bending Moment Mallow = 200 200 lb-in.

M < Mallow [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)

Smax = ( β2 q b 2 ) / t2 (At center) a / b 1 1.2 1.4 1.6 1.8 2.000 β1 0.3078 0.3834 0.4356 0.468 0.4872 0.4974 0.500 β2 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 = 1.800m a = Longer Dimension b = 0.652m b = Shorter Dimension a / b = 2.76

β2 = 0.25 ( See Table Above )

Check Plate Stresses Against Load Combination 1 ( DL + Lr + Pe )

Total Design Load (p = q = DL + Lr + Pe) = 5.60 kPa

In Shorter Direction Smax = 17 MPa < 148.33MPa [Satisfactory] In Longer Direction Smax = 126 MPa < 148.33MPa [Satisfactory]

Check Adequacy Against Load Combination 2 ( DL + Pi )

Total Design Load (p = q = DL + Lr + Pe) = 4.40 kPa

In Shorter Direction Smax = 13 MPa < 148.33MPa [Satisfactory] In Longer Direction Smax = 99 MPa < 148.33MPa [Satisfactory]

(7)

7) CALCULATION FOR ROOF STIFFENER Flange Breadth 55mm Thk. 6mm Web Depth 94mm Thk. 6mm

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 Ic A Yc A x Yc 2 mm mm mm4 mm2 mm mm4 6 94 415292 564 25.00 352500 55 6 990 330 25.00 206250

Moment of Inertia of Built Up Tee Section = 975032 mm4

Section Modulus Zprov'd = 34823 mm3

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,

Mmax = 2.7 kN-m W x a2 / 8

Zreq'd = 27270 mm3 Mmax / (0.6 x Fym)

[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. I = Ic + A x Yc 2 Roof Plate mm4 207240 767792

(8)

9) STABILITY OF TANK AGAINST WIND LOAD (ASCE 7-05)

Wind velocity V = 155 kph = 43 m/s

Roof Height Above Shell HR = 0.04 m Considering 40 mm Thk. Insulation @ Roof

Shell Height H = 1.90 m

Height of Tank Including Roof Height HT = 1.94 m

Effective Wind Gust Factor G = 0.85 ASCE 7-05,6.5.8.1

Force Co- Efficient Cf = 0.80 By Interpolation (ASCE 7-05, Fig. 6-21) Wind Directionally Factor Kd = 1.3 600-58H-0010

Velocity Pressure Exposure Co-Eff. Kz = 0.85 ASCE 7-05, Chapter 6, Table 6-3

Topo Graphic Factor Kzt = 1

Importance Factor I = 1.15 600-58H-0010

Design Wind Pressure qz = 0.613 x Kz x Kzt x Kd x V 2

xI/1000

1.440 kN/m2 ASCE 7-2005, Chapter 6, Eq. 6-15, Clause 6.5.10

Effective Tank Diameter (De) 600-58H-0010

Insulation Thickness = 40 mm

(OD + 2 x insulation Thk.) x Kd = 2.460 m (OD + 2 x insulation Thk.) + 0.6 = 2.492 m

De = 2.492 m 600-58H-0010

Effective Projected Area (Ae = De x H)

Effective Area Projected Ae = 4.83 m2 600-58H-0010

Design Wind Load P1 = qz x G x Cf x Ae 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: 0.6 Mw + MPi < MDL / 1.5 Case 2: Mw + 0.4MPi < ( MDL + MF ) / 2

Mw = P1 x H / 2 MPi = Pi x A X D / 2

MDL = (Weight of shell + roof + bottom) x D / 2

Mw = 4.6 kN-m = ft-lbs

MPi = 0 kN-m

MDL = 6.9 kN-m

MF = 0 For no fluid in the tank

Case 1: < [Satisfactory]

Case 2: < [Unsatisfactory]

[Anchorage against wind pressure is required]

Greater of

5

5 3

3387

(9)

9.1) Resistance To Sliding: API 650 3.11.4

The wind load pressure on projected area = 0.86 kN/m2 = 18.0 psf (API 650, Chapter 3, Clause 3.2.1 (f))

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

Tank OD Do = 1.812 m

Design Wind Velocity V = 155 kph

Velocity Factor Vf = (V/190)2 = 0.666

Wind Pressure on vertical plane surfaces = 0.86 kN/m2 (API 650, Chapter 3, Clause 3.2.1 (f))

Wind Pressure on vertical conical surfaces = 1.44 kN/m2 (API 650, Chapter 3, Clause 3.2.1 (f))

Projected area of roof = 0.036 m2

Projected area of shell = 4.73 m2

Fwind = Vf (Wind Pressure on Roof x Projected Area of Roof + Wind Pressure on Shell x Projected Area of Shell)

= 2.74 kN (API 650, Chapter 3, Clause 3.2.1 (f))

Ffriction = Maximum of 40% of Weight of Tank

= 12.27 kN (API 650, Chapter 3, Clause 3.11.4)

[Anchorage against sliding is not required]

PENTAGON PENTAGON PENTAGON PENTAGON PENTAGON PENTAGON H/2 for Uniform pressure

(10)

10) Stability Calculations Against Seismic Load (As per API 650 Addendum Four 2005 )

D = m Nominal dia of Tank

H = m Maximum design product level

D/H =

H/D =

Site Class =

Corroded thickness of bottom plate tb = mm Corroded thickness of 1st shell course ts = mm

Over turning ring wall moment

Mrw = sqrt{[Ai(WiXi+WsXs+WrXr)] 2

+ [Ac(WcXc)] 2

} As per API 650 E.6.1.5 For Site class 'E' As per API 650 E.4.9.1

Ai = 2.5 x Q x Fa x So ( I / Rwi ) As per Equation E-4

Acceleration-based site coefficient Fa = From Table E-1

Scaling Factor Q = As per API 650 E.4.9.1

Ss =

S1 =

So = As per E.4.2.c

=

Rwi = From Table E-4

I = 600-58H-0010

Ai = As per Equation E-4

As per Equation E-6, For seismic design categories E & F,

Ai ≥ 0.5S1(I/Rwi) As per Equation E-6 ≥

Condition staisfied

Wi = Effective impulse weight of the liquid When D/H <1.33

Wi = (1-0.218D/H)Wp As per Equation E-14 Wp = Weight of content based on design specific gravity of the product

= KN

= N

Wi = KN

= N

When D/H < 1.33 As per E-6.1.2.1

Xi = Height from the bottom of the shell to the center of action of the lateral Siesmic force related to impulsive liquid force

Xi = As per Equation E-17

= m

Ws = Total Weight of Shell and appurtenances (Uncorroded)

= KN

Xs = Height from the bottom of the tank shell to center of gravity

= m

Wr = Total Weight of fixed tank roof including framing (Uncorroded)

= KN

Xr = Height from the top of the shell to the roof and roof appurtenances center of gravity

= 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 = As per Equation E-3

= sqrt (tanh (3.68H/D)) 0.58 0.78 30 1.28 0.00 0.00 0.578 0.006 46.48 46482 36.85 36850 (0.5-0.094D/H)H 0.04 0.4 X Ss 0.04 4 1.25 0.08 6.00 2.5 1 0.1 E 6.00 1.806 1.900 0.95 1.05

(11)

Therefore

Tc = As per E.4.8.2

TL = As per E.4.9.1

When TC < TL As per E.4.9.1

Ac = 2.5 x Q x Fa x So x (Ts /Tc) x (I/Rwc) ≤Ai As per Equation E-7 Where

Ts = As per API 650 E-2

S1 =

Fv = From Table E-2

Rwc = From Table E-4

Ts =

Ac =

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

= KN

= 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

= m

Therefore Ring Wall Moment

Mrw = KN-m

= N-m = ft-lbs

Resisting force to be adequate for tank stability J<1.54

Anchorage Ratio J = As per API 650 E.6.2.1.1.1

D2

(wt(1-0.4Av)+wa)

Where Av = As per API 650 E.6.1.3

SDS = From Equation E-4

=

Av =

wa = 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

= As per API 650 E-2

=

ta = Corroded thickness of the bott. plate under the shell extending at the distance L from the inside of the shell

ta = mm

wa = N/m ≤ N/m

wa = N/m

wa KN/m

wt = As per API 650 E.6.2.1.1

wrs = Roof load acting on the tank shell (Uncorroded)

= KN/m

= N/m

wt = KN/m

Therefore = N/m

Anchorage Ratio J = <

Condition staisfied Tank is self anchored

0 5.37 5373 0.312 1.54 10391 4.2 4.2 0.004 [(Ws/πD)+wrs)] 0.000 2.5 x Q x Fa x So 0.3 0.035 G x (1-0.4 x Av) 0.97 6.00 1.70 5.40 5404 3985 Mrw 0.14 x SDS 3.5 2 0.56 0.06 10.15 10153 1.40 4 (FvS1) / (FaSs) 0.04

(12)

10.1) Shell Compression In Mechanically Anchored Tanks As per API 650 E.6.2.2.2

= Mpa

10.2) Allowable Longitudinal Membrane Compression Stress in Tank Shell As per API 650 E.6.2.2.3

Calculating value of

= When GHD2 / t2 is less than 44, then

Fc = {(83x ts)/(2.5 x D)} + 7.5 x sqrt(G x H) < 0.5 x Fty Where = = Therefore, Fc = Mpa

As ơc < Fc Condition staisfied

10.3) Seismic Base Shear (As Per E.6.1)

V = Total Design Base Shear (N)

Vi = Design Base Shear Due to Impulsive Component (N) Vc = Design Base Shear Due to Convective Component (N)

Vi = Vi = 5260.4 N Vc = AcWc Vc = 635.11 N V = Sqrt(Vi 2 + Vc 2 ) V = 5298.6 N V = 5.2986 kN 83.335 1.26 G x H x D2 t2 121 Ai(Ws+Wr+Wf+Wi) 0.17 G X H 1.862 0.5 X Fty

(13)

11) ANCHORAGE FOR UPLIFT LOAD CASES, PER API 650 TABLE 3-21B

P = ATM kPa

= 0.00 in. of water

Test Pressure Pt = 0.00 kPa

= 0.00 in. of water

Dead Load of Shell Minus Any CA and Any Dead Load Other Than Roof

W1 = Weight of shell (Corroded)

= N

= lbs

Dead Load of Shell Minus Any CA and Any Dead Load Including Roof Plate Acting on the Shell Minus Any CA

W2 = Weight of shell (Corroded) + Weight of Roof (corroded)

= N

= 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

W3 = Weight of Shell

= N

= lbs

Yield stress for Anchor Bolts

Fy = 36000psi SA 307 Gr. B

th = 6 mm = 0.23622 in.

D = 1.806 m = 5.92 ft

MS = 5.404 kN-m = 3985 ft-lbs (From Seismic Calculation)

U = Net Uplift Load N = No. of Anchor Bolts Ar = Required Bolt Area

15076 *Fy For Anchor Bolts

(PSI)

Design Pressure + Wind Test Pressure Wind Load Design Pressure

Design Pressure + Seismic

Seismic Load 0.019 Ar = tb/Fall 15076 1219.5 1219.5 6807.7 5424.6 1530.43

NET UPLIFT FORMULA, U (lbf)

15076

15076 15076 Table 3 - 21

UPLIFT LOAD CASES

Design Pressure 199 0.013 8.52 0.020 300 -1490.05 756.36 ((Pt - 8th) x D 2 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 lbs ((P - 8th) x D 2 x 4.08) - W1 -373 in.2 290 Seismic Load

Design Pressure + Wind Design Pressure +Seismic

UPLIFT LOAD CASES

((P-8th) x D² x 4.08) + (4 x Mw/D)-W1 tb = U / N Test Pressure -0.025 1160.79 796.74 5424.58 -1490.05 12.85 -15.94 8.09 12.42 1201.17 15076 mm2 -15.94 Wind Load -0.025 0.013 -373 189

(14)

As per API 650, Chapter 3, Clause 3.1.1.3

Design Tension Load Per Anchor = 4MW/dN - W/N

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 kN

Design Tension Load Per Anchor = 200 lbs

Required Bolt Area Areq. = 13 mm2

Provided Bolt Area Aprov. = 539mm2 (Uncorroded Root Area)

= 443 mm2

(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 = [P(0.375g-0.22d)/Sf]0.5

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]

Consider M30 Bolt P Jmin g a Ød f e C h

(15)

Anchor Chair Height Calculations:

Sind. = (Pe/t2)[{1.32*Z/(1.43*a*h2/Rt)+(4ah2)0.333}+{0.031/(Rt)0.5}]

Z = Reduction Factor = 1/[{.177am(m/t)2 /(Rt)0.5

}+1]

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.

Sall. = Allowable Stress = 21.51 ksi

Z = 0.9849

Sind. = 0.409 ksi

[Anchor Chair Height Is Adequate]

Gusset Plate Thickness Calculations: Jmin

Gusset Plate Thickness = 0.218 in. = 5.5 mm

Gusset Plate Thickness Provided = 14mm = 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

(16)

14) 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 Lr = kN/m2

Area of Roof Ar = m2

Total Live Load WL = Lr x Ar = kN

Circumference of Tank C = π x D = m

Live Load transferred to Foundation LL = WL / C = kN/m

Dead load transferred to foundation

Self Weight of Roof + Stiffeners Wr = kN

Self Weight of Bottom Plate Wb = kN

Self Weight of Shell Ws = kN

Self Weight of shell Attachments Wa = kN

Total Dead Load acting on shell Wr + Ws + Wa = kN

Dead Load Transferred to Foundation Wd = DL = kN/m

Operating & Hydrostatic Test Loads

Self Weight of Tank Wr + Ws + Wa + Wb = kN = kgs

Weight of Fluid in Tank at Operating Conditions Wf = kN = kgs Weight of Water in Tank at Hydrotest Conditions Ww = kN = kgs Uniform Load Operating Condition = (Self wt.+ Fluid)/Area Wo = kN/m2

Uniform Load Hydrotest Condition = (Self wt.+ Water)/Area Wh = kN/m2

Wind Load Transferred to Foundation

Base Shear due to wind load Fw = kN

Reaction due to wind load Rw = kN/m

Moment due to wind load Mw = kN-m

Seismic Load Transferred to Foundation

Reaction due to seismic load Rs = kN/m

Moment due to seismic load Ms = kN-m

Base Shear due to seismic load FS = kN

2.60 24.02 1.38 5.40 4.59 0.55 3.12 5.69 5.30 0.52 1.20 4835 0.45 4.73 30.83 1.35 3990 5.42 5.42 32.18 3282 28.02 31.07 47.41 39.13

(17)

Summary of Foundation Loading Data kN/m kN/m kN/m2 kN/m2 kN kN/m kN-m kN kN/m kN-m

Note : Consider 15-20% variation in weight while designing the foundation

5.40 Dead load, shell, roof & ext. structure loads DL = 5.42

Moment due to wind load Base shear due to wind

Ms =

Reaction due to wind

Mw= Fw = Wh= Rs = 28.02 5.30 31.07 Uniform load, operating condition

Reaction due to seismic load

Wo =

Moment due to seismic load

0.52 0.45 4.73 4.59 Live load 0.55 Rw = Uniform load, hydrotest load

LL =

(18)

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)

t

d

=

4.9D (H

L1

- 0.3)G + CA

t

t

=

4.9D (H

L1

- 0.3)

t

d

= Design shell thickness, mm

6.51585

mm

t

t

= Hydrostatic test shell thickness, mm

4.84512

mm

G = Specific Gravity of Fluid to be Stored

=

1

D = Nominal Dia. of Tank

=

14.008

m

H

L1

= Design Liquid Level

=

12

m

CA = Corrosion Allowance

=

0

mm

S

d

= Allowable Stress for Design Condition

=

145

MPa

S

t

= Allowable Stress for Hydrostatic condition

=

195

MPa

E = Weld Joint Efficiency

=

0.85

Table S4

0.85

Width of course

(including curb angle)

W

1

=

2

m

Design Height for Shell Course

H

L1

=

12

m

Design Shell Thickness

t

d

=

6.515851

mm

Hydrostatic Test Thickness

t

t

=

4.84512

mm

The designed thickness of the course

=

8

mm

Shell Plates Weight Summary

Shell Course

1

Shell Width, m

2.00

Shell Thickness, mm (Uncorroded)

8.00

Shell Thickness, mm (Corroded)

8.00

Shell Weight, kN (Uncorroded)

2.75

Shell Weight, kN (Corroded)

2.75

Shell Internal Diameter

m

Di

14

Shell External Diameter

m

Do

14.016

Mean Diamter of the Shell course m

D

14.008

Design Shell Thickness

(S

d

) (E)

Hydrostatic Test Thickness

(19)
(20)

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)

t

d

=

4.9D (H

L1

- 0.3)G + CA

t

t

=

4.9D (H

L1

- 0.3)

t

d

= Design shell thickness, mm

5.39895

mm

t

t

= Hydrostatic test shell thickness, mm

4.0146

mm

G = Specific Gravity of Fluid to be Stored

=

1

D = Nominal Dia. of Tank

=

14

m

H

L1

= Design Liquid Level

=

10

m

CA = Corrosion Allowance

=

0

mm

S

d

= Allowable Stress for Design Condition

=

145

MPa

S

t

= Allowable Stress for Hydrostatic condition

=

195

MPa

E = Weld Joint Efficiency

=

0.85

Table S4

0.85

Width of course

(including curb angle)

W

1

=

2

m

Design Height for Shell Course

H

L1

=

10

m

Design Shell Thickness

t

d

=

5.398945

mm

Hydrostatic Test Thickness

t

t

=

4.0146

mm

c

m

Shell External Diameter

m

The designed thickness of the course 1

=

6 mm

Shell Plates Weight Summary

Shell Course

1

Shell Width, m

2.00

Shell Thickness, mm (Uncorroded)

0.00

Shell Thickness, mm (Corroded)

0.00

Shell Weight, kN (Uncorroded)

0.00

Shell Weight, kN (Corroded)

0.00

Shell Internal Diameter

m

Di

14

Shell External Diameter

m

Do

14.012

Mean Diamter of the Shell course m

D

14.006

Design Shell Thickness

(S

d

) (E)

Hydrostatic Test Thickness

(21)
(22)

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)

t

d

=

4.9D (H

L1

- 0.3)G + CA

t

t

=

4.9D (H

L1

- 0.3)

t

d

= Design shell thickness, mm

4.28576

mm

t

t

= Hydrostatic test shell thickness, mm

3.18685

mm

G = Specific Gravity of Fluid to be Stored

=

1

D = Nominal Dia. of Tank

=

14

m

H

L1

= Design Liquid Level

=

8

m

CA = Corrosion Allowance

=

0

mm

S

d

= Allowable Stress for Design Condition

=

145

MPa

S

t

= Allowable Stress for Hydrostatic condition

=

195

MPa

E = Weld Joint Efficiency

=

0.85

Table S4

0.85

Width of course

(including curb angle)

W

1

=

2

m

Design Height for Shell Course

H

L1

=

8

m

Design Shell Thickness

t

d

=

4.285761

mm

Hydrostatic Test Thickness

t

t

=

3.186848

mm

c

m

Shell External Diameter

m

The designed thickness of the course 3

Shell Plates Weight Summary

Shell Course

1

Shell Width, m

2.00

Shell Thickness, mm (Uncorroded)

0.00

Shell Thickness, mm (Corroded)

0.00

Shell Weight, kN (Uncorroded)

0.00

Shell Weight, kN (Corroded)

0.00

Shell Internal Diameter

m

Di

14

Shell External Diameter

m

Do

14.012

Mean Diamter of the Shell course m

D

14.006

Design Shell Thickness

(S

d

) (E)

Hydrostatic Test Thickness

(23)
(24)

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)

t

d

=

4.9D (H

L1

- 0.3)G + CA

t

t

=

4.9D (H

L1

- 0.3)

t

d

= Design shell thickness, mm

2.6591

mm

t

t

= Hydrostatic test shell thickness, mm

2.3591

mm

G = Specific Gravity of Fluid to be Stored

=

1

D = Nominal Dia. of Tank

=

14

m

H

L1

= Design Liquid Level

=

6

m

CA = Corrosion Allowance

=

0

mm

S

d

= Allowable Stress for Design Condition

=

173

MPa

S

t

= Allowable Stress for Hydrostatic condition

=

195

MPa

E = Weld Joint Efficiency

=

0.85

Table S4

0.85

Width of course

(including curb angle)

W

1

=

2

m

Design Height for Shell Course

H

L1

=

6

m

Design Shell Thickness

t

d

=

2.659096

mm

Hydrostatic Test Thickness

t

t

=

2.359095

mm

The designed thickness of the course

Shell Plates Weight Summary

Shell Course

1

Shell Width, m

2.00

Shell Thickness, mm (Uncorroded)

0.00

Shell Thickness, mm (Corroded)

0.00

Shell Weight, kN (Uncorroded)

0.00

Shell Weight, kN (Corroded)

0.00

Shell Internal Diameter

m

Di

14

Shell External Diameter

m

Do

14.012

Mean Diamter of the Shell course m

D

14.006

Design Shell Thickness

(S

d

) (E)

Hydrostatic Test Thickness

(25)
(26)

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)

t

d

=

4.9D (H

L1

- 0.3)G + CA

t

t

=

4.9D (H

L1

- 0.3)

t

d

= Design shell thickness, mm

1.72608

mm

t

t

= Hydrostatic test shell thickness, mm

1.53134

mm

G = Specific Gravity of Fluid to be Stored

=

1

D = Nominal Dia. of Tank

=

14

m

H

L1

= Design Liquid Level

=

4

m

CA = Corrosion Allowance

=

0

mm

S

d

= Allowable Stress for Design Condition

=

173

MPa

S

t

= Allowable Stress for Hydrostatic condition

=

195

MPa

E = Weld Joint Efficiency

=

0.85

Table S4

0.85

Width of course

(including curb angle)

W

1

=

2

m

Design Height for Shell Course

H

L1

=

4

m

Design Shell Thickness

t

d

=

1.72608

mm

Hydrostatic Test Thickness

t

t

=

1.531342

mm

The designed thickness of the course

Shell Plates Weight Summary

Shell Course

1

Shell Width, m

2.00

Shell Thickness, mm (Uncorroded)

0.00

Shell Thickness, mm (Corroded)

0.00

Shell Weight, kN (Uncorroded)

0.00

Shell Weight, kN (Corroded)

0.00

Shell Internal Diameter

m

Di

14

Shell External Diameter

m

Do

14.012

Mean Diamter of the Shell course m

D

14.006

Design Shell Thickness

(S

d

) (E)

Hydrostatic Test Thickness

(27)
(28)

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)

t

d

=

4.9D (H

L1

- 0.3)G + CA

t

t

=

4.9D (H

L1

- 0.3)

t

d

= Design shell thickness, mm

0.79306

mm

t

t

= Hydrostatic test shell thickness, mm

0.70359

mm

G = Specific Gravity of Fluid to be Stored

=

1

D = Nominal Dia. of Tank

=

14

m

H

L1

= Design Liquid Level

=

2

m

CA = Corrosion Allowance

=

0

mm

S

d

= Allowable Stress for Design Condition

=

173

MPa

S

t

= Allowable Stress for Hydrostatic condition

=

195

MPa

E = Weld Joint Efficiency

=

0.85

Table S4

0.85

Width of course

(including curb angle)

W

1

=

2

m

Design Height for Shell Course

H

L1

=

2

m

Design Shell Thickness

t

d

=

0.793064

mm

Hydrostatic Test Thickness

t

t

=

0.70359

mm

The designed thickness of the course

Shell Plates Weight Summary

Shell Course

1

Shell Width, m

2.00

Shell Thickness, mm (Uncorroded)

0.00

Shell Thickness, mm (Corroded)

0.00

Shell Weight, kN (Uncorroded)

0.00

Shell Weight, kN (Corroded)

0.00

Shell Internal Diameter

m

Di

14

Shell External Diameter

m

Do

14.012

Mean Diamter of the Shell course m

D

14.006

Design Shell Thickness

(S

d

) (E)

Hydrostatic Test Thickness

(29)

(S

d

) (E)

(30)

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

Z=(D² H2/17)* (V/190)²

WHERE Z= REQUIRED MINIMUM SECTION MODULUS

cm

D= NOMINAL TANK DIAMETER

=

14.008

METERS

H2 HIGHT OF THE TANK

=

12 METERS

V= DESIGN SPEED OF THE WIND (3-SEC GUST)

165 KM/HOUR

Z

=

104.4589

cm

INTERMEDIATE WIND GIRDERS

according to clause 5.9.7.1 of API 650, the maximum hight of the unstiffened shel shall be

calculated as follows:

as

H1 = 9.47 * t * ((t/D)

ᵌ)^0.5 * (190/V)²

WHERE

H1= VERTICAL DISTANCE IN M, BETWEEN THE INTERMEDIATE WIND GIRDER AND

TOP ANLE OF THE SHELL (meters)

H1

=

21.12045

m

t = AS ORDERED THICKNESS UNLESS OR OTHER WISE SPECIFIED OF THE

THINNEST SHELL COURSE(mm)

t

=

6

mm

D = NOMINAL SHELL DIAMETER (m)

=

14.008

m

V = 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 shell

H1 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 transposed

width 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)

=

mm

W = actual width of th shell course (mm)

=

mm

t uniform = as ordered thickness of the thinest shell course (mm)

=

mm

t actual = as ordered thickness of the shell course for which transposed width has to be calculated

(31)
(32)
(33)

For course 1 having thickness 8 mm recommended

Wtr = W((tuniform)/(t actual))^(5/2)

Wtr

=

974.2786

mm

W

=

2000

mm

t uniform

=

6

mm

t actual

=

8

mm

all courses from 2 to 6 having thickness of 6 mm recommended

Wtr

=

2000

mm

W

=

2000

mm

t uniform

=

6

mm

t 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 meters

as 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

(34)

References

Related documents