API 650 Design Tanks

CONTENTS:-

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)

1)

DESIGN DATA

Design Code

API STANDARD 650 TENTH EDITION, NOVEMBER 1998 ADDENDUM 4, DECEMBER 2005 APPENDICES: J, M & S "Process Equipment Design"

Flat Roof 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

Specific Gravity of Contents

G

=

0.980

Material's Yield Strength @ Design Temperature

Fym

=

166.67

Design Temperature

TDSN

=

130

o

Operating Temperature

TOPR

=

80

o

Design Internal Pressure

Pi

=

ATM

C kPa

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)

Bottom

=

0

mm

Shell

=

0

mm

Roof

=

0

mm

Structure

=

0

mm degree (Flat Roof)

kg/m3 MPa

(As Per Table S-5)

C 0

Corrosion Allowance

Slope of Tank Roof

q

=

0

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

Wc

=

0.348

kN

Weight of Top Curb Angle Weight of Roof Attachments

(Assumed)

W ra

=

10

kN

(Nozzles, Insulation, Railing/Platform)

Weight of Shell Attachments

(Assumed)

W sa

=

14

kN

(Nozzles, Insulation, Ladder & Partition Plates)

V

=

155

kph

Modulus of Elasticity @ Design Temperature

E

=

Live Load on Roof

Lr

=

Design Wind Velocity

2)

185000 MPa 1.20

kPa

(Table S-6) (PIP VESTA002, 3.2.D)

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

td

=

4.9D (HL1 - 0.3)G + CA

Hydrostatic Test Thickness

tt

=

4.9D (HL1 - 0.3)

(Sd) (E) (St) (E) 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 HL1 = Design Liquid Level

= =

1.806 1.900

m m

CA = Corrosion Allowance Sd = Allowable Stress for Design Condition

= =

0 148.33

mm MPa

St = Allowable Stress for Hydrostatic condition

=

186.00

E = Weld Joint Efficiency

=

0.85

MPa (Table S-4)

Shell Course W1

=

1.900 m

HL1

=

1.900 m

Design Shell Thickness

td

=

0.110 mm


tt

=

0.090 mm

Shell Thickness Provided

t1

=

6.00

mm

Total Shell Weight (Uncorroded)

=

5.08

kN

Total Shell Weight (including partition plates) (Corroded)

=

5.08

kN

x =

6 780

Thk.

Weight of Top Curb Angle (Uncorroded)

=

0.35

kN

Weight of Top Curb Angle (Corroded)

=

0.35

kN

Width of course

(Including Curb Angle)

Design Height for Shell Course

az Shell Course

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

Top Curb Angle

(Formed Section) Cross-sectional Area of the Top Curb Angle

3)

1

Shell Width, m

L

65

x

65

mm2

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 Used Bottom Plate Thickness

tb

=

tb

=

5

mm

tb used

=

6.00

mm

5+ CA 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 Used Bottom Plate Thickness

tb

=

6

mm

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)

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

Nominal Tank Diameter

D

=

1.806 m

Design Wind Speed

V

=

Maximum Height of the Unstiffened Shell

H1

=

517.01 m

=

0.9585

=

495.58 m

Modification Factor as per S.3.6.7

=

Modulus Of Elasticity at Design Temp.

155

mm kph

Modulus Of Elasticity at 40oC *Maximum Height of the Unstiffened Shell (Modified As Per S.3.6.7)

H1

Transformed Shell Height As per API 650, Chapter 3, Clause 3.9.7.2 Transposed width of each shell course W tr = 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 W tr1 = W 1 x (ttop/t1)5/2

Transformed Height of Tank Shell

t1

=

6.00

W tr1

=

1900 mm

Htr

=

1900 mm

=

1.90

[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.

mm

m

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 wl 2 / 24 occurs at the midspan. M max = -w l 2 / 12 = -p(1) l 2 / 12 = -p l 2 / 12

Over supporting rafters

M max = -w l 2 / 24 = -p(1) l 2 / 24 = -p l 2 / 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 = bt 2 / 6 where b = width of beam, inches, and, t = thickness of beam, inches. a = Di

For this case, b = 1.0 in. Hence, z = t2 / 6

l=b

f = p l 2 / 2t 2 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

Loadings & Critical Combinations Dead Load

DL

=

kPa 4.40

psi 0.64

lb/in. 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

UNIT

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

ENDS

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 Allowable Bending Stresses

z

= =

0.009

0.009

in.3

21513

21513

psi

Allowable Bending Moment

M allow

=

200

200

lb-in.

Fb M < M allow

[Satisfactory]

(Fb = Sd)

[ Table S - 5 ]

Check Adequacy Against Load Combination 2 ( DL + Pi ) MID

ENDS 25.67

UNIT in.

0.638

lb/in. lb-in.

Length of beam (strip) between stiffeners

l

=

25.67

Load Combination 2

p

=

0.638

Induced Bending Moment

M

=

18

35

Thickness of the beam (strip)

t

=

0.236

0.236

in.

Section Modulus Allowable Bending Stresses

z

0.009

0.009

in.3

Fb

= =

21513

21513

psi

Allowable Bending Moment

M allow

=

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 b2 ) / t2

(At center) 1.8 0.4872

2.000 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/b β1

1 1.2 1.4 0.3078 0.3834 0.4356

a

=

b

=

a/b β2

= =

1.6 0.468

1.800 m 0.652 m

a = Longer Dimension b = Shorter Dimension

2.76 0.25

( See Table Above )

Check Plate Stresses Against Load Combination 1 ( D L + Lr + Pe ) (p = q = DL + Lr + Pe)

Total Design Load

=

5.60

kPa

In Shorter Direction

Smax =

17 MPa

<

148.33 MPa

[Satisfactory]

In Longer Direction

Smax =

126 MPa

<

148.33 MPa

[Satisfactory]

Check Adequacy Against Load Combination 2 ( DL + Pi ) (p = q = DL + Lr + Pe)

Total Design Load

=

4.40

kPa

In Shorter Direction

Smax =

13 MPa

<

148.33 MPa

[Satisfactory]

In Longer Direction

Smax =

99 MPa

<

148.33 MPa

[Satisfactory]

(Fb = Sd)

7)

CALCULATION FOR ROOF STIFFENER

Flange Breadth

55

mm

6

mm

94

mm

6

mm

Thk. Web Depth Thk.

Roof 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

Ic

A 4

Yc 2

A x Yc2

I = Ic + A x Yc2

4

mm

mm

mm

mm

mm

mm

mm4

6

94

415292

564

25.00

352500

767792

55

6

990

330

25.00

206250

207240

Moment of Inertia of Built Up Tee Section

=

4 975032 mm

Section Modulus

Zprov'd

=

3 34823 mm

Span of Stiffener

a

=

1.80 m

Self Weight of Stiffener

=

0.16 kN

Weight of Roof Plate Within Stiffined Section Weight of Roof Attachments

= =

0.55 kN 10.00 kN

Live Load on Roof

=

1.41 kN

=

6.73 kN/m

Mmax

=

2.7 kN-m

Zreq'd

=

Total Design Load Per Unit Length

W

(Approx.) (Nozzles, Insulation, Railing/Platform)

Considering simply supported end conditions for the stiffener,

27270 mm3

[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.

W x a2 / 8 Mmax / (0.6 x Fym)

9)

STABILITY OF TANK AGAINST WIND LOAD

(ASCE 7-05)

Wind velocity

V

=

155

kph

Roof Height Above Shell

HR

=

0.04

m

=

43

m/s

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

Velocity Pressure Exposure Co-Eff.

Kz

=

0.85

Topo Graphic Factor

Kzt

=

1

Importance Factor

I

=

Design Wind Pressure

qz

=

Considering 40 mm Thk. Insulation @ Roof

600-58H-0010 ASCE 7-05, Chapter 6, Table 6-3

1.15

600-58H-0010

0.613 x Kz x Kzt x Kd x V2 x I/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

(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 Area Projected

Ae

=

4.83

m2

600-58H-0010

Design Wind Load

P1

=

Greater of

mm

Effective Projected Area (Ae = De x H)

=

qz x G x Cf x Ae 4.73

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

MPi

=

0 kN-m

MDL

=

6.9 kN-m

MF

=

=

3387

ft-lbs

For no fluid in the tank

0

Case 1:

3

<

5

[Satisfactory]

Case 2:

5

<

3

[Unsatisfactory]

[Anchorage against wind pressure is required]

kN

ASCE 7-05, Chapter 6, Eq. 6-28, Clause 6.5.15

9.1)

Resistance To Sliding:

H/2 for Uniform pressure

The wind load pressure on projected area

=

API 650 3.11.4 0.86 kN/m2

=

PENTAGON PENTAGON

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

=

Design Wind Velocity

V

=

155

=

0.666

Wind Pressure on vertical plane surfaces

=

0.86

kN/m2


Wind Pressure on vertical conical surfaces

=

1.44

2


Projected area of roof

=

0.036 m2

Projected area of shell

=

4.73

Vf

Velocity Factor

Fwind

= =

Ffriction

= =

=

(V/190)2

1.812 m kph

kN/m m2

Vf (Wind Pressure on Roof x Projected Area of Roof + Wind Pressure on Shell x Projected Area of Shell) 2.74 kN


Maximum of 40% of Weight of Tank 12.27 kN

[Anchorage against sliding is not required]

(API 650, Chapter 3, Clause 3.11.4)

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

tb

=

6.00

mm

Corroded thickness of 1st shell course

ts

=

6.00

mm

Over turning ring wall moment Mrw For Site class 'E'

=

As per API 650 E.4.9.1 Ai =

sqrt{[Ai(WiXi+WsXs+WrXr)]2 + [Ac(WcXc)]2}

As per API 650 E.6.1.5

2.5 x Q x Fa x So ( I / Rwi )

As per Equation E-4

Acceleration-based site coefficient

Fa

=

2.5

From Table E-1

Scaling Factor

Q Ss

= =

1 0.1

As per API 650 E.4.9.1

S1

=

0.04

So

=

0.4 X Ss

=

0.04

As per E.4.2.c

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, 0.5S1(I/Rwi) Ai ≥

As per Equation E-6

≥

0.006

Condition staisfied Wi

=

Effective impulse weight of the liquid

Wi

=

(1-0.218D/H)Wp

Wp

=

Weight of content based on design specific gravity of the product

When D/H <1.33

Wi When D/H < 1.33 Xi

As per Equation E-14

=

46.48

KN

= =

46482 36.85

N KN

=

36850

N

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

Xi Ws

=

(0.5-0.094D/H)H

=

0.78

= =

Xs

= =

Wr

= =

Xr

= =

As per Equation E-17 m

Total Weight of Shell and appurtenances (Uncorroded) 30

KN

Height from the bottom of the tank shell to center of gravity 1.28

m

Total Weight of fixed tank roof including framing (Uncorroded) 0.00

KN

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

Tc

=

1.8 x Ks x sqrt (D)

Ks

=

Sloshing peroid cofficient

Ks

= =

0.578 sqrt (tanh (3.68H/D)) 0.58

As per Equation E-2a As per Equation E-3

As per E 4.8.2

Therefore Tc TL When TC < TL

= =

1.40 4

As per E.4.8.2 As per E.4.9.1

As per E.4.9.1 2.5 x Q x Fa x So x (Ts /Tc) x (I/Rwc) ≤ Ai

Ac

=

Ts

=

(FvS1) / (FaSs)

S1

=

0.04

Fv Rwc

= =

3.5 2

Ts

=

0.56

Ac

=

0.06

As per Equation E-7

Where

Wc

From Table E-2 From Table E-4

=

Effective Convective (sloshing)portion of the liquid Weight

=

0.23 x (D/H) Tanh (3.67 H/D) x Wp

= = Xc

As per API 650 E-2

10.15

KN

10153

N


=

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

=

1.70


m

Therefore Ring Wall Moment Mrw

=

5.40

KN-m

=

5404

N-m

=

3985

ft-lbs

Resisting force to be adequate for tank stability J<1.54 Anchorage Ratio J

=

Mrw

As per API 650 E.6.2.1.1.1

D2(wt(1-0.4Av)+wa) Where

Av

=

0.14 x SDS

SDS

=

2.5 x Q x Fa x So

=

0.3

Av wa

=

As per API 650 E.6.1.3 From Equation E-4

= 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

ta

=

=

Effective specific gravity including vertical seismic effects

=

G x (1-0.4 x Av)

=

0.97

As per API 650 E-2

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

ta

=

6.00

mm

wa

=

10391

N/m

wa

=

4.2

N/m

wt

=

[(Ws/πD)+wrs)]

wrs

=

wa

wt

0.004

≤

4.2

N/m

KN/m As per API 650 E.6.2.1.1

Roof load acting on the tank shell (Uncorroded)

=

0.000

KN/m

= =

0 5.37

N/m KN/m N/m

Therefore

=

5373

Anchorage Ratio J

=

0.312

<

1.54

Condition staisfied Tank is self anchored As Anchors Are Being Provided, The Tank Will Be Considered As Mechanically Anchored

10.1)

Shell Compression In Mechanically Anchored Tanks

= 10.2)

As per API 650 E.6.2.2.2

1.26

Mpa

Allowable Longitudinal Membrane Compression Stress in Tank Shell

As per API 650 E.6.2.2.3

G x H x D2

Calculating value of

t2 =

0.17

When GHD2 / t2 is less than 44, then Fc

=

{(83x ts)/(2.5 x D)} + 7.5 x sqrt(G x H)

GXH 0.5 X Fty

= =

1.862 83.335

Fc

=

121

Where

Therefore, Mpa

As ơc < Fc Condition staisfied

10.3)

Seismic Base Shear

(As Per E.6.1)

V Vi

= =

Total Design Base Shear (N) Design Base Shear Due to Impulsive Component (N)

Vc

=

Design Base Shear Due to Convective Component (N)

Vi

=

Ai(Ws+Wr+Wf+Wi)

Vi

=

Vc

=

AcW c

Vc

=

635.11

V

=

Sqrt(Vi2 + Vc2)

V

=

5298.6

N

V

=

5.2986

kN

5260.4 N

N

<

0.5 x Fty

11)

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

Test Pressure

P

=

ATM

kPa

Pt

= =

0.00 0.00

in. of water 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)

=

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 W2

=

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 W3

=

Weight of Shell

=

5424.6 N 1219.5 lbs

= Yield stress for Anchor Bolts Fy

=

th

=

D MS

= =

36000 psi

SA 307 Gr. B

6 mm

=

1.806 m 5.404 kN-m

= =

0.23622 in. 5.92 ft 3985 ft-lbs

(From Seismic Calculation)

Table 3 - 21 NET UPLIFT FORMULA, U (lbf)

UPLIFT LOAD CASES

*Fy For Anchor Bolts (PSI)

Design Pressure

((P - 8th) x D2 x 4.08) - W 1

-1490.05

15076

Test Pressure

((Pt - 8th) x D2 x 4.08) - W 1

-1490.05

15076

Wind Load

(4 x Mw / D) - W 2

756.36

15076

Seismic Load

(4x Ms/D) -W 2

1160.79

15076

Design Pressure +Seismic

((P-8th) x D² x 4.08) + (4 x Ms/D)-W1

1201.17

15076

Design Pressure + Wind

((P-8th) x D² x 4.08) + (4 x Mw/D)-W1

796.74

15076

UPLIFT LOAD CASES

tb = U / N

Ar = tb/Fall

lbs

in.2

mm2

Design Pressure Test Pressure

-373 -373

-0.025 -0.025

-15.94 -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

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

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

=

No. of Anchor Bolts Weight of shell plus roof supported by the shell less 0.4 times the force due to internal pressure Design Tension Load Per Anchor

N W

= = =

Required Bolt Area Provided Bolt Area

Consider M30 Bolt

2.000 m 4 Nos. 6 kN 200 lbs

Areq.

=

13 mm2

Aprov.

=

539 mm2

(Uncorroded Root Area)

=

443 mm2

(Corroded Root Area)

[Area of the anchor bolt provided is sufficient] ANCHOR CHAIR CALCULATIONS

P e

C

12)

a

h

As Per AISI E-l, Volume ll, Part Vll

g

Jmin

Ød

f

Top Plate Thickness Calculations: C = [P(0.375g-0.22d)/Sf]0.5

Top Plate Thickness C

=

Top Plate Thickness

S f

= =

Stress At Point

=

25

ksi

Distance From Outside of

=

0.98

in.

g

=

Distance between Gusset Plates

=

3.94

in.

d

=

Anchor Bolt Diameter (corroded)

=

1.06

in.

=

0.45

kips

(AISI E-1)

Top Plate to Edge Of Hole

P

Design Load or Max. Allowable =

Anchor Bolt Load or 1.5 Times 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]

Anchor Chair Height Calculations: (Pe/t2)[{1.32*Z/(1.43*a*h2/Rt)+(4ah2)0.333}+{0.031/(Rt)0.5}]

Sind.

=

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

=

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

(including repad)

1/[{.177am(m/t)2/(Rt)0.5}+1]

ksi

[Anchor Chair Height Is Adequate] Jmin

Gusset Plate Thickness Calculations:

0.04 ( h - C ) or 1/2"

Gusset Plate Thickness

=

Gusset Plate Thickness Provided

=

[Gusset Plate Thickness Is Adequate]

13)

WEIGHT SUMMARY Empty

=

Weight of Working Fluid

=

Operating Weight

=

Weight of Test Fluid

= =

Test Weight (Full of water)

3282 kg 3990 kg 7272 kg 4835 kg 8117 kg

(Considering HLL = 1600mm)

0.218 in. 14 mm

= =

5.5 mm 0.551 in.

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

=

1.20

kN/m2

Area of Roof

Ar

=

2.60

m2

Total Live Load

W L = Lr x Ar

=

3.12

kN

Circumference of Tank

C=πxD

=

5.69

m

Live Load transferred to Foundation

LL = W L / C

=

0.55

kN/m

Self Weight of Roof + Stiffeners

Wr

=

1.38

kN

Self Weight of Bottom Plate

Wb

=

1.35

kN

Self Weight of Shell

Ws

=

5.42

kN

Self Weight of shell Attachments

Wa

=

24.02

kN

Total Dead Load acting on shell

Wr + Ws + Wa

=

30.83

kN

Dead Load Transferred to Foundation

W d = DL

=

5.42

kN/m

Dead load transferred to foundation

Operating & Hydrostatic Test Loads Wr + Ws + Wa + W b = 32.18

kN

=

3282

kgs

Weight of Fluid in Tank at Operating Conditions

W f = 39.13

kN

=

3990

kgs

Weight of Water in Tank at Hydrotest Conditions

W w = 47.41

kN

=

4835

kgs

Uniform Load Operating Condition = (Self wt.+ Fluid)/Area

W o = 28.02

kN/m

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

W h = 31.07

kN/m2

Self Weight of Tank

2

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

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

FS

=

5.30

kN

Seismic Load Transferred to Foundation

Summary of Foundation Loading Data Dead load, shell, roof & ext. structure loads

DL =

5.42

Live load

LL =

0.55

kN/m

Uniform load, operating condition

Wo =

28.02

kN/m2

Uniform load, hydrotest load

W h=

31.07

kN/m2

Base shear due to seismic

FS=

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

Fw =

4.73

kN

Reaction due to wind

Rw =

0.45

kN/m

Moment due to wind load

Mw=

4.59

kN-m

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

kN/m

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) td


=

4.9D (HL1 - 0.3)G + CA (Sd) (E)


tt

=

td = Design shell thickness, mm

4.9D (HL1 - 0.3) (St) (E)

6.51585

tt = Hydrostatic test shell thickness, mm G = Specific Gravity of Fluid to be Stored D = Nominal Dia. of Tank HL1 = Design Liquid Level CA = Corrosion Allowance Sd = Allowable Stress for Design Condition

= = = = =

St = Allowable Stress for Hydrostatic condition E = Weld Joint Efficiency

= =

4.84512 1 14.008 12 0 145 195 0.85

0.85


HL1


td


tt

= = = =

The designed thickness of the course

=

8

Width of course

W1

(including curb angle)

Shell Plates Weight Summary Shell Course Shell Width, m Shell Thickness, mm (Uncorroded) Shell Thickness, mm (Corroded) Shell Weight, kN (Uncorroded) Shell Weight, kN (Corroded) Shell Internal Diameter m Shell External Diameter m Mean Diamter of the Shell course m

Di Do D

2

mm mm

m

12

m

6.515851

mm

4.84512

mm

mm

1 2.00 8.00 8.00 2.75 2.75 14 14.016 14.008

m m mm MPa MPa Table S4

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

td

=


tt

=

4.9D (HL1 - 0.3)G + CA (Sd) (E) 4.9D (HL1 - 0.3) (St) (E)

td = Design shell thickness, mm tt = Hydrostatic test shell thickness, mm G = Specific Gravity of Fluid to be Stored D = Nominal Dia. of Tank HL1 = Design Liquid Level CA = Corrosion Allowance Sd = Allowable Stress for Design Condition

= = = = =


= =

5.39895

mm

4.0146

mm

1 14 10 0 145 195 0.85

0.85 Width of course

W1



HL1


td

Hydrostatic Test Thickness c Shell External Diameter

tt

2

m

10

m

5.398945

mm

4.0146

mm

m m =

The designed thickness of the course 1

Shell Plates Weight Summary Shell Course Shell Width, m Shell Thickness, mm (Uncorroded) Shell Thickness, mm (Corroded) Shell Weight, kN (Uncorroded) Shell Weight, kN (Corroded) Shell Internal Diameter Shell External Diameter Mean Diamter of the Shell course m

= = = =

m m

Di Do D

6 mm

1 2.00 0.00 0.00 0.00 0.00 14 14.012 14.006


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

td

=


tt

=



4.28576

mm


3.18685

mm

= = = = =


= =

1 14 8 0 145 195 0.85


W1



HL1


td

Hydrostatic Test Thickness c Shell External Diameter

tt

= = = =

2

m

8

m

4.285761

mm

3.186848

mm

m m

The designed thickness of the course 3


m m

Di Do D

1 2.00 0.00 0.00 0.00 0.00 14 14.012 14.006


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

td

=


tt

=



2.6591

mm


2.3591

mm

= = = = =


= =

1 14 6 0 173 195 0.85


W1



HL1


td


tt

= = = =

2

m

6

m

2.659096

mm

2.359095

mm



m m

Di Do D

1 2.00 0.00 0.00 0.00 0.00 14 14.012 14.006



td

=


tt

=



1.72608

mm


1.53134

mm

= = = = =


= =

1 14 4 0 173 195 0.85


W1



HL1


td


tt

= = = =

2

m

4

m

1.72608

mm

1.531342

mm



m m

Di Do D

1 2.00 0.00 0.00 0.00 0.00 14 14.012 14.006



td

=


tt

=



0.79306

mm


0.70359

mm

= = = = =


= =

1 14 2 0 173 195 0.85


W1



HL1


td


tt

= = = =

2

m

2

m

0.793064

mm

0.70359

mm



m m

Di Do D

1 2.00 0.00 0.00 0.00 0.00 14 14.012 14.006


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 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

cmᵌ

cmᵌ

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 = mm

For course 1 having thickness 8 mm recommended Wtr = W((tuniform)/(t actual))^(5/2) Wtr W t uniform t actual

= = = =

974.2786 2000 6 8

mm mm mm mm

all courses from 2 to 6 having thickness of 6 mm recommended Wtr W t uniform t actual

= = = =

2000 2000 6 6

mm mm mm 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

TANK CONICAL ROOF

API 650 Design Tanks

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