AGENDA ITEM: 650-600 Aluminum Tank Appendix

DATE: May 2, 2005

CONTACT: Randy Kissell, TGB PartnershipPH: 919-644-8250 FX: 919-644-8252, email: randy.kissell@tgbpartnership.com

PURPOSE: Provide rules for aluminum tanks

REVISION: 1

IMPACT: Including aluminum tanks in 650 will reduce the cost to owners and manufacturers to maintain a standard for aluminum tanks and provide additional options for tank material.

RATIONALE:

ASME hasn’t maintained their standard on aluminum tanks (B96.1), which API tank standards 620 and 650 reference for floating roofs and LNG inner tanks. API PV&T committee members would have to spend more time updating B96.1 than adding an aluminum tank appendix to 650, since an appendix can utilize the 650 steel provisions with only slight modifications.

Similar to Appendix S for stainless tanks, the Appendix for aluminum tanks includes only those provisions that differ from steel tank requirements.

This second ballot addresses affirmative comments and the negative received in the first ballot.

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Ballot to Add an Aluminum Tank Appendix to API 650

1) Change the title of API 650:

Welded Steel Tanks for Oil Storage

2) Change Foreword:

“This standard is based on the accumulated knowledge and experience of purchasers and manufacturers of welded steel oil storage tanks …”

3) “1.1.1 This standard covers material, design, fabrication, erection, and testing requirements for vertical, cylindrical, aboveground, closed- and open-top, welded steel storage tanks …”

4) Add: “1.1.24 Appendix AL provides requirements for aluminum tanks.”

5) Add to Table 1-1:Appendix Title StatusAL Aluminum Storage Tanks Requirements

6) Change 8.1.1k: The maximum operating temperature, in degrees Celsius (Fahrenheit) (unless other units are specified by the purchaser), which shall not exceed 90oC (200oF) except in cases where Appendix M or Appendix AL appliesy.”

7) Change H.4.3.2: “Welded joints between aluminum members shall conform to Section 3.1 of ASME B96.1” and AL.5.1.

8) Change Appendix M.1.2 Note: “An exception may be made by the purchaser for Items d and e, if the following criteria are met: a. Allowable stress reductions for aluminum alloys are determined in accordance with ANSI/ASME B96.1, Welded Aluminum Alloy Storage Tanks Appendix AL, and alloys are evaluated for the potential of exfoliation.”

9) Add Appendix AL as shown below:

Key: red italics = commentary

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APPENDIX AL – ALUMINUM STORAGE TANKS

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AL.1 Scope

AL.1.1 Construction. This appendix provides material, design, fabrication, erection, and testing requirements for vertical, cylindrical, aboveground, closed- and open top, welded aluminum storage tanks constructed of the alloys specified in AL.4.This wording follows Appendix S.

AL.1.2 Requirements. This appendix states only the requirements that differ from the rules in this standard. For requirements not stated, the rules of this standard shall be followed.This wording was chosen to match Appendix S.

AL.1.3 Temperature. This appendix applies for maximum design temperatures up to 200oC [400oF]. Alloys 5083, 5086, 5154, 5183, 5254, 5356, 5456, 5556, and 5654 shall not be used if the maximum design temperature exceeds 65oC [150oF].400oF is the maximum temperature addressed in B96.1. Alloys 5083, 5086, 5154, 5183, 5254, 5356, 5456, 5556, and 5654 have more than 3% nominal magnesium content and become susceptible to exfoliation corrosion if held at temperatures above 150oF.

AL.1.4 Units. Use consistent units in this Appendix’s equations. For example, in an equation, use inches for all lengths (stress in lb/in2 and tank diameter in inches) or use mm for all lengths (stress in N/mm2 and tank diameter in mm).

AL.2 References

The following publications are cited in this appendix. The latest edition shall be used unless otherwise noted.

ASTM A 193 Alloy-Steel and Stainless Steel Bolting Materials for High-Temperature ServiceA 194 Carbon and Alloy Steel Nuts for Bolts for High Pressure or High Temperature Service, or BothB 209 Aluminum and Aluminum-Alloy Sheet and PlateB 209M Aluminum and Aluminum-Alloy Sheet and Plate [Metric]

B 210 Aluminum and Aluminum-Alloy Drawn Seamless TubesB 210M Aluminum and Aluminum-Alloy Drawn Seamless Tubes [Metric]B 211 Aluminum and Aluminum-Alloy Bar, Rod, and WireB 211M Aluminum and Aluminum-Alloy Bar, Rod, and Wire [Metric]B 221 Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and TubesB 221M Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes [Metric]B 241/B 241M Aluminum and Aluminum-Alloy Seamless Pipe and Seamless Extruded TubeB 247 Aluminum and Aluminum-Alloy Die Forgings, Hand Forgings, and Rolled Ring ForgingsB 247M Aluminum and Aluminum-Alloy Die Forgings, Hand Forgings, and Rolled Ring Forgings [Metric]B 308/B 308M Aluminum-Alloy 6061-T6 Standard Structural ProfilesB 345/B 345M Aluminum and Aluminum-Alloy Seamless Pipe and Seamless Extruded Tube for Gas and Oil Transmission and Distribution Piping SystemsB 928 High Magnesium Aluminum Alloy Sheet and Plate for Marine ServiceF 467 Nonferrous Nuts for General UseF 467M Nonferrous Nuts for General Use [Metric]F 468 Nonferrous Bolts, Hex Cap Screws, and Studs for General UseF 468M Nonferrous Bolts, Hex Cap Screws, and Studs for General Use [Metric]F 593 Stainless Steel Bolts, Hex Cap Screws, and StudsF 594 Stainless Steel Nuts

AWSA5.10/A5.10M Specification for Bare Aluminum and Aluminum-Alloy Welding Electrodes and RodsD1.2 Structural Welding Code – Aluminum

AA1

Aluminum Design Manual (ADM)1 The Aluminum Association Inc., 900 19th Street, N.W. Washington, D.C. 20006. www.aluminum.org

AL.3 Definitions

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For the purposes of this appendix, the following definitions apply:

Aluminum: Aluminum and aluminum alloys.

AL.4 Materials

AL.4.1 General. Alloys shall be selected from Table AL-1. Dimensional tolerances shall meet the material specifications given in AL.4. Impact testing and toughness verification are not required.Aluminum does not have a brittle fracture transition temperature; it is more ductile at lower temperatures.

AL.4.2 Sheet and Plate. Sheet and plate shall meet ASTM B 209 or B 928. Tapered thickness plate may be used.

AL.4.3 Rod, Bar, and Structural Shapes. Rod, bar, and shapes shall meet ASTM B 211, B 221, or B 308.

AL.4.4 Pipe and Tube. Pipe and tube shall meet ASTM B 210, B 241, or B 345.

AL.4.5 Forgings. Forgings shall meet ASTM B 247.

AL.4.6 Flanges. Flanges shall meet ASTM B 247 and be 6061-T6. Flange dimensions shall meet ASME B16.5 or B16.47.

AL.4.7 Bolting.

AL.4.7.1 Aluminum. Aluminum bolts shall meet ASTM F 468. Aluminum nuts shall meet ASTM F 467. Bolts and nuts of 2024 alloy shall have an anodic coating at least 0.005 mm [0.0002 in.] thick. Bolts shall not be welded.B96.1 Table 8 called for bolts to meet F 468. Aluminum rivets are no longer used.

AL.4.7.2 Stainless Steel. Stainless steel bolts shall meet ASTM F 593 alloy group 1 or 2, or ASTM A 193 B8. Stainless steel nuts shall meet ASTM F 594 alloy group 1 or 2 or ASTM A 194 Grade 8.

AL.4.7.3 Carbon Steel. Carbon steel bolts shall be galvanized.

B96.1 included aluminized steel bolts, but they are no longer available and so are not included here.

AL.4.8 Welding Electrodes. Welding electrodes shall meet AWS A5.10/A5.10M and shall be chosen in accordance with AWS D1.2. AL.5 Design

AL.5.1 Joints

AL.5.1.1 Typical Joints(a) Bottom plates under the shell thicker than 8 mm [5/16 in.] shall be butt welded.

(b) Butt-Welded Bottom Joints. The butt welds may be made from both sides or from one side and shall have complete penetration and complete fusion. In the latter case, a backing strip 5 mm [3/16 in.] or thicker, of an aluminum alloy compatible with the bottom plate, shall be tacked to one of the plates, and the intersection joints of the strips shall be welded with full fusion.

AL.5.1.2 Roof and Top Angle Joints. The moment of inertia of the top angle and contributing portion of the shell shall equal or exceed that provided by the sizes listed below:

Diameter (m) Size (mm)D < 11 64 x 64 x 6.411 < D < 18 64 x 64 x 7.918 < D 76 x 76 x 9.5

Diameter (ft) Size (in.)D < 35 2 ½ x 2 ½ x ¼35 < D < 60 2 ½ x 2 ½ x 5/1660 < D 3 x 3 x 3/8

The top angle requirements given in 650 3.1.5.9 and B96.1 3.3.4(a) differ:Diameter (ft) 650 B96.1D < 35 2 x 2 x 3/16 2.5 x 2.5 x ¼35 < D < 60 2 x 2 x ¼ 2.5 x 2.5 x 5/1660 < D 3 x 3 x 3/8 3 x 3 x 3/8The B96.1 angles for tanks under 60 ft have approximately the same bending stiffness (EI) as the API 650 sizes. For tanks over 60 ft diameter, the B96.1 bending stiffness is about 1/3 that of 650.

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AL.5.2 Bottoms

AL.5.2.1 Annular Bottom Plate WidthAnnular bottom plates shall have a radial width that meets the requirements of 3.5.2 except that the width must equal or exceed

wheretb = thickness of the annular bottom plateFty = yield strength of the bottom plateγw = density of waterG = design specific gravity of the stored liquidH = maximum design liquid levelThis dimensionless equation gives the same results as the one in B96.1 3.2.2(f).

AL.5.2.2 Annular Bottom Plate Thickness The thickness of annular bottom plates shall equal or exceed the requirements given in Table AL-5.This table is B96.1 Table 3.

AL.5.3 Shells

The required minimum thickness of the shell plates shall be the greater of the calculated design shell thickness including any corrosion allowance or the hydrostatic test shell thickness, but the shell thickness shall not be less than required by Table AL-6:

td =

tt =

where

td = design shell thicknesstt = hydrostatic test shell thicknessγw = density of waterD = nominal diameter of tank (see 3.6.1.1)H = design liquid level (see 3.6.3.2)A = 0.3 m (1 ft)G = specific gravity of the liquid to be stored, as specified by the purchaserEj = joint efficiency, 1.0, 0.85, or 0.70 (see Table AL-2)CA = corrosion allowance, as specified by the purchaser (see 3.3.2)

Sd = allowable stress for the design condition (see Table AL-7)St = allowable stress for hydrostatic test condition (see Table AL-7)St ambient has been added and is based on the lesser of 0.85 Fy and 2/3Fu

AL.5.4 Shell Openings

AL.5.4.1 Thermal Stress Relief Thermal stress relief requirements of 3.7.4 do not apply.

AL.5.4.2 Shell Manholes Shell manholes shall meet 3.7.5 except:

(1) Cover Plate and Flange Thickness: The cover plate and flange thickness shall comply with Figures AL-1 and AL-2. As an alternative to Figures AL-1 and AL-2, plate flanges may be designed in accordance with API 620 rules using the allowable stresses from Table AL-7.

(2) Neck Thickness: Where manhole neck thickness is controlled by thickness of the bolting flange (see note b of Table 3-4), the flange thickness determined in (1) above shall be used.

B96.1 requires ½” min for manhole necks, no matter the shell thickness. I propose we follow the API methodology for determining neck thickness which is based on both shell thickness and flange thickness requirements.

(3) Weld Sizes: Fillet Weld A shall comply with Table AL-8.

The weld sizes in Table 3-7 (weld A) for nozzles larger than 2” are smaller than those used in B96.1. The allowable shear stress on aluminum welds compared to steel is less when comparing base material tension allowables. Therefore, use B96.1 weld sizes.

AL.5.4.3 Nozzles Shell nozzles shall meet 3.7.6 except fillet weld A shall be per Table AL-7 requirements.

AL.5.4.4 Flush Type CleanoutsFlush-type cleanout fittings shall comply with Figures AL-1, AL-2, and AL-3.

AL.5.5 Wind Girders

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The length of the shell included in the area of wind girders shall be 0.424 except for

unstiffened shell above top wind girders, the length shall be . This is different than the 16t rule in 650 (which is based on 95t/√Fty) and accounts for the different modulus of elasticity of aluminum vs. steel.

AL.5.5.1 Wind GirdersThe section modulus of wind girders shall equal or exceed

Z =

wherep = (1.48 kPa)(V/V190)2

[p = (31 lb/ft2)(V/V120)2]V = 3 sec gust design wind speed (see 3.2.1(f))V120 = 190 km/hr [120 mph]H = for top wind girders on tanks with no intermediate wind girder, the tank height; for tanks with intermediate wind girders, the vertical distance between the intermediate wind girder and the top angle of the shell or the top wind girder of an open-top tank.D = tank diameter E = modulus of elasticity of the wind girderc = lesser of the distances from the neutral axis to the extreme fibers of the wind girderThis dimensionless equation includes a safety factor of 2, comparable to 650 3.9.6.1. This equation does not use 650’s approach, which assumes a girder width to tank diameter ratio > 0.015, because the ratio is larger for aluminum and varies considerably by diameter, so using one value for all cases would be too conservative. The equation given here is different from B96.1 because B96’s equation left the allowable stress as a variable but did not provide the allowable buckling stress of the wind girder.

AL.5.5.2 Intermediate Wind GirdersThe height of the unstiffened shell shall not exceed

H1 =

whereH1 = vertical distance between the intermediate wind girder and the top angle of the shell or the top wind girder of an open-top tank● t = as ordered thickness, unless otherwise specified, of the top shell course

D = nominal tank diameter This equation is the same as in B96.1except dimensionless. Since 650 and B96.1 assume elastic buckling of the wind girder, the only difference between them is the modulus of elasticity.

AL.5.6 Roofs

AL.5.6.1 Structural Members The minimum nominal thickness of structural members shall be 4 mm [0.15 in.]. 650’s minimum for steel is 0.17”, but aluminum is less corrosion-prone and standard aluminum shapes have webs with 0.15” thickness.

AL.5.6.2 Frangible Roofs Roofs required to be frangible shall meet the requirements of 3.10.2.6 except that the cross sectional area A of the roof-to-shell joint shall not exceed 0.159W/(Fy tanθ) where Fy is the greatest yield strength of the materials in the joint.This equation is the general form of the one in 3.10.2.6, which assumes Fy = 32 ksi for all cases.

AL.5.6.3 Allowable StressesRoofs shall be proportioned so that stresses from the load combinations specified in 3.10.2.1 do not exceed the allowable stresses given in the Aluminum Design Manual (ADM) Specification for Aluminum Structures – Allowable Stress Design for building type structures. Allowable stresses for ambient temperature service shall be calculated using the minimum mechanical properties given in the ADM. Allowable stresses for elevated temperature service shall be calculated using the minimum mechanical properties given in Table AL-3. Section 3.10.3.4 does not apply.This approach simplifies what B96.1 has. In B96.1, not all of the elevated temperature properties are given, but rather, allowable stress expressions are given in numerous tables (Tables 10 thru 15). These tables are out of date (for example, Table 15 bearing stresses are based on the 1994 ADM; bearing stresses were revised in the 2000 ADM).

AL.5.6.4 Supported Cone Roofs(a) The thickness and span of roof plates shall be such that the stresses determined from Figure AL-4 do not exceed the allowable stresses given

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in Table AL-4 for dead load and for dead and live loads.Figure AL-4 is the same as B96.1 Figure 12, which provided a quick way to determine roof plate stress given the load and plate span and thickness.

(b) The roof supporting structure shall be of 6061-T6 or 6063-T6 and proportioned so stresses do not exceed allowable stresses. Dead load stresses for temperatures over 120oC [250oF] shall not exceed 25% of allowable stresses. It is unlikely dead load stresses will exceed 25% of allowable, since the dead load is usually less than 5 psf (3/16” plate is 2.7 psf) and dead + live load will be at least 22.1 psf under the load combinations in 650.

AL.5.6.5 Self-Supporting Cone Roofs(a) The roof thickness shall equal or exceed

whereD = tank diameter p = maximum roof pressure loadE = modulus of elasticity of the roof (see Table AL-3)θ = roof slope to horizontalThis dimensionless equation matches 650 3.10.5.1 (a simplified elastic buckling expression for a cone) but includes the modulus as a variable. It includes the same combined knockdown for imperfections and safety factor as 650. This can be proved by the following example: For D = 80 ft, θ = 20o, p = 60 psf, and E = 29,000,000 lb/in2, the above formula gives

t = = 0.673”

API 650 3.10.5.1gives

t = = 0.675”

(b) The area of the roof-to-shell joint determined using Figure F-2 shall equal or exceed

pD2/(8f tanθ)wherep = maximum roof pressure loadD = diameter of the tankf = least allowable tensile stress of the materials in the roof-to-shell joint

θ = angle to horizontal made by the roof at the shellThis dimensionless equation is the same as given in B96.1, just slightly rewritten for simplicity. It matches 650 3.10.5.2.

AL.5.6.6 Self-Supporting Dome and Umbrella Roofs(a) The roof thickness shall equal or exceed

whererr = roof radiusp = maximum roof pressure loadE = modulus of elasticity of the roof (see Table AL-3)This dimensionless equation matches 650 3.10.6.1 (elastic buckling of a sphere) but includes the modulus as a variable. It includes the same combined knockdown for imperfections and safety factor as 650. This can be proved by the following example: For D = 60 ft, rr = 1.0D, p = 60 psf, and E = 29,000,000 lb/in2, the above formula gives

t = = 0.345 in.

API 650 3.10.6.1gives

t = = 0.346 in.

(b) The area of the roof-to-shell joint determined using Figure F-2 shall equal or exceed

pD2/(8f tanθ)wherep = maximum roof pressure loadD = diameter of the tankf = least allowable tensile stress of the materials in the roof-to-shell jointθ = angle to horizontal made by the roof at the shellThis dimensionless equation is the same as given in B96.1, just slightly rewritten for simplicity. It matches 650 3.10.6.2 except it includes the roof slope as a variable whereas 650 conservatively uses the lowest roof slope for all cases.

AL.5.6.6 Structurally Supported Aluminum Dome RoofsStructurally supported aluminum dome roofs shall meet Appendix G.

AL.6 FabricationAPI 650-600 5/2/05 8

AL.6.1 Finish of Plate Edges At least 3 mm [1/8 in.] shall be mechanically removed from edges of heat treatable alloys that have been plasma arc cut. Oxygen cutting shall not be used.

AL.6.2 Marking Materials Marking materials shall not contain carbon or heavy metal compounds.

AL.7 Erection

AL.7.1 Welding Methods Welding shall be gas metal arc welding, gas tungsten arc welding, plasma arc welding without using flux, or friction stir welding. The welding may be performed manually, automatically, or semi-automatically according to procedures by welders qualified in accordance with ASME Section IX.

AL.7.2 Preheating Parts to be welded shall not be preheated except to the extent needed to drive off moisture or bring base metal temperature up to minimum welding temperature per 5.2.1.2.

AL.7.3 Plumbness The plumbness requirements shall be per 5.5.2 except the out-of-plumbness in one shell course shall not exceed the flatness tolerance in ASTM B 209M [B 209].

AL.7.4 Storage Aluminum parts shall not be stored in contact with one another when moisture is present. Aluminum shall not be stored or erected in contact with carbon steel or the ground.This is to prevent water staining and rust marks.

AL.8 Inspection of Welds

AL.8.1 Liquid Penetrant ExaminationThe following welds shall be examined by the liquid penetrant method before the hydrostatic test of the tank:

a) Shell opening reinforcement and structural attachment plates, excluding lightly loaded attachments, that intersect a shell weld shall be examined for a distance of 150 mm [6 in.] on

each side of the intersection and the butt weld for a distance of 50 mm [2 in.] beyond the pad weld.

b) All welds of openings in the shell that are not completely radiographed, including nozzle and manhole neck welds and neck-to-flange welds.

c) All butt-welded joints in tank shell and annular plate on which backing strips are to remain.B96.1 did not include PT, but these rules are used here since PT is relatively cost effective.

AL.8.2 Magnetic Particle ExaminationSection 6.2 does not apply.

AL.9 Welding Procedures and Welder Qualifications

Weld procedures and welder qualifications shall meet Section 7 except that impact tests are not required.

AL.10 Marking

AL.10.1 MaterialIn addition to the requirements of Section 8, the bottom and roof alloys shall be shown on the nameplate.

AL.11 Foundations

AL.11.1 Concrete Aluminum shall not be placed in direct contact with concrete.

AL.12 Internal Pressure

AL.12.1 General. Appendix F shall be met with the following exceptions.

AL.12.2 Design Pressure. The design pressure in F.4.1 shall be

P =

where P = design pressure for the tankA = area resisting the compressive force, as illustrated in Figure F-2Fy = yield strength of the materials in the top joint

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θ = angle between the roof and a horizontal plane at the roof-to-shell junctureSF = safety factor = 1.6D = tank diameter ρ = density of the roof plateth = nominal roof thickness

AL.12.3 Maximum Design Pressure. The maximum design pressure in F.4.2 shall be

Pmax =

wherePmax = maximum design pressure ρ = density of the roof plateth = nominal roof thickness W = weight of the shell and any framing (but not roof plates) supported by the shellM = wind overturning momentD = diameter of the tank

AL.12.4 Required Compression Area tat the Roof-to-Shell Junction. The required area at the roof-to-shell junction in F.5.1 shall be

A =

AL.12.5 Calculated Failure Pressure. The calculated failure pressure in F.6 shall be Pf = 1.6P – ρth

AL.12.6 Anchored Tanks. The allowable compressive stress in F.7.2 shall be Fy /1.6.

AL.13 Seismic Design

AL.13.1 General. Appendix E shall be met with the following exceptions.

AL.13.2 Allowable Longitudinal Membrane Compression Stress in Tank Shell. The allowable compressive stress in E.6.2.2.3 shall be established by rational analysis.

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Table AL-1 Material SpecificationsSheet and Plate Rod, Bar, and

ShapesPipe and Tube Forgings

Alloy Temper Alloy Temper Alloy Temper Alloy Temper1060 all 1060 all 1060 all1100 all 1100 all 1100 all 1100 H1123003 all 2024 T4 3003 all 3003 H112

Alclad 3003 all Alclad 3003 all3004 all 3004 all

Alclad 3004 all5050 all 5050 all5052 all 5052 all 5052 all5083 all 5083 all 5083 all 5083 H111,

H1125086 all 5086 all 5086 all5154 all 5154 all 5154 all5254 all 5254 all5454 all 5454 all 5454 all5456 all 5456 all 5456 all5652 all 5652 all6061 (1) 6061 T6 6061 T4, T6 6061 T6

Alclad 6061 (1)6063 T5, T6 6063 T5, T6

(1) Includes T4, T42, T451, T6, T62, T651 tempers

Table AL-2 Joint EfficiencyJoint Efficiency (Ej) Shell Radiograph Requirements

1.00 Full Radiography required for all vertical joints. Horizontal joints per 0.85 joint efficiency requirements

0.85 Radiography per 6.1.2 except additional random spot radiography in first course vertical seams is not required.

0.70 No shell radiography required

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Table AL-3 Minimum Mechanical PropertiesMinimum Tensile Yield Strengths Fty (ksi) at Temperatures (oF)Alloy Temper 100 150 200 250 300 350 4001060 all 2.5 2.5 2.4 2.2 1.9 1.8 1.61100 all 3.5 3.5 3.5 3.4 3.2 2.8 2.43003 all 5.0 5.0 5.0 4.9 4.6 4.3 3.7Alclad 3003 all 4.5 4.5 4.5 4.4 4.1 3.9 3.33004 all 8.5 8.5 8.5 8.5 8.5 8.0 7.4Alc 3004 all 8.0 8.0 8.0 8.0 8.0 7.2 6.75050 all 6.0 6.0 6.0 6.0 6.0 5.8 5.65052, 5652 all 9.5 9.5 9.5 9.5 9.5 9.5 8.45083 (1) all 18 17.9 – – – – –5083 (2) all 17 16.9 – – – – –5086 all 14 13.9 – – – – –5154, 5254 all 11 11 – – – – –5454 all 12 12 12 12 11.9 11.6 11.15456 (1) all 19 18.8 – – – – –5456 (2) all 18 17.9 – – – – –6061, Alclad 6061

T4, T6 welded

15 15 15 15 14.7 13.2 10.5

6061 T6 extrusions

35 35 33.6 29.1 23.6 14.9 7.9

6063 T5, T6 welded

8 8 8 8 7.5 4.5 3.4

6063 T6 25 25 23 19.8 16.1 8.9 5.2(1) thickness up to 1.5000 in.(2) thickness 1.501 to 3.000 in.(3) strengths are for the –O temper for all alloys except 6061, Alclad 6061, and 6063 which are as noted.

This table matches B96.1 Table 22 except for 6061 and 6063. For unwelded 6061 and unwelded 6063, which are not in B96.1, strengths have been linearly interpolated from Kaufman’s Properties of Aluminum Alloys, using the least strength for any time at elevated temperature and assuming strengths up to 150F equal the 75F strengths. For welded 6061 and welded 6063, strengths are from B96.1 Table 22 but converted from 10” gage lengths to 2” gage lengths (by multiplying by 0.75) to follow the change in the Aluminum Design Manual 2005. Alloys 5083, 5086, 5154, 5183, 5254, 5356, 5456, 5556, and 5654 have more than 3% nominal magnesium content and become susceptible to exfoliation corrosion if held at temperatures above 150oF, so no strengths are shown for these cases.

Minimum Tensile Ultimate Strengths Ftu (ksi) at Temperatures (oF)Alloy Temper 100 150 200 250 300 350 4001060 all 8.0 8.01100 all 11 113003 all 14 14Alclad 3003 all 13 133004 all 22 22Alclad 3004 all 21 215050 all 18 185052, 5652 all 25 255083 (1) all 40 40 – – – – –5083 (2) all 39 39 – – – – –5086 all 35 35 – – – – –5154, 5254 all 30 30 – – – – –5454 all 31 31

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5456 (1) all 42 42 – – – – –5456 (2) all 41 41 – – – – –6061, Alclad 6061

T4, T6 welded

24 24

6061 T6 extrusions

38 38 35.3 30.2 24.5 16.9 11.0

6063 T5, T6 welded

17 17

6063 T6 30 30 27.2 23.2 18.9 12.0 7.7(1) thickness up to 1.500 in.(2) thickness 1.501 to 3.000 in.(3) strengths are for the –O temper for all alloys except 6061, Alclad 6061, and 6063 which are for the

tempers and conditions noted in the table.Ultimate strengths in this table match B96.1 tables 4 and 9 for 100oF temperature except for 6061 and 6063. For6061 and 6063 unwelded, strengths have been linearly interpolated from Kaufman’s Properties of Aluminum Alloys, using the least strength for any time at elevated temperature and assuming strengths up to 150F equal the 75F strengths. Strengths at other elevated temperatures are not included now but places are left for them to be provided in the future should there be a need for such service.

Compressive Moduli of Elasticity E (ksi) at Temperature (oF)Alloy 100 150 200 250 300 350 4001060 10,100 9,900 9,700 9,400 9,200 8,800 8,4001100 10,100 9,900 9,700 9,400 9,200 8,800 8,4003003, Alclad 3003 10,100 9,900 9,700 9,400 9,200 8,800 8,4003004, Alclad 3004 10,100 9,900 9,700 9,400 9,200 8,800 8,4005050 10,1005052, 5652 10,300 10,000 9,800 9,400 9,100 8,600 8,1005083 10,400 10,200 – – – – –5086 10,400 10,200 – – – – –5154, 5254 10,300 – – – – –5454 10,300 10,000 9,800 9,400 9,100 8,600 8,1005456 10,400 10,200 – – – – –6061 10,100 9,900 9,700 9,500 9,300 9,100 8,8006063 10,100 9,900 9,700 9,500 9,300 9,100 8,800(1) Tensile moduli = (compressive moduli)/ 1.02.The moduli for 6061 and 6063 are the ones that produce the allowable stresses in B96.1 Tables 11, 12, and 13 for S > S2 and also match 1.02Et from Kaufman Properties of Aluminum Alloys for 100, 200 (212), 300, 350, and 400oF. Other alloys are from Kaufman’s personal data. Italicized values were determined by interpolation. ASME BPVC Section II, Part D, Table TM-2 provides average E values ([Ec +Et]/2) for 70, 200, 300, and 400oF.

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Table AL-4 Allowable Stresses (ksi) for Roof PlatesAlloy Temper 100 150 200 250 300 350 4003003 all (dead load) 3.15 2.4 1.8 1.4

(dead + live load) 5.0 5.0 5.0 4.9 4.6 4.3 3.7Alclad 3003 all (dead load) 2.85 2.15 1.6 1.25

(dead + live load) 4.5 4.5 4.5 4.4 4.15 3.85 3.353004 all (dead load) 5.75 3.8 2.35

(dead + live load) 8.5 8.5 8.5 8.5 8.5 8.0 7.4Alclad 3004 all (dead load) 5.15 3.4 2.4

(dead + live load) 8.0 8.0 8.0 8.0 8.0 7.2 6.655050 all (dead load) 5.35 2.8 1.4

(dead + live load) 6.0 6.0 6.0 6.0 6.0 5.8 5.65052, 5652 all (dead load) 6.25 4.1 2.35

(dead + live load) 9.5 9.5 9.5 9.5 9.5 9.5 8.45083 all (dead + live load) 18 17.9 – – – – –5086 all (dead + live load) 14 13.9 – – – – –5154, 5254 all (dead + live load) 11 11 – – – – –5454 all (dead load) 11.7 7.4 5.5 4.1 3.0

(dead + live load) 12 12 12 12 11.9 11.6 11.15456 all (dead + live load) 19 18.8 – – – – –6061, Alclad 6061

T4, T6 (dead load) 8.2 6.1 4.3

(dead + live load) 9.6 9.6 9.6 9.45 8.85 7.45 5.65NotesFor non-heat treatable alloys, allowable stresses for dead + live loads are the lesser of the yield strength, the stress producing a secondary creep rate of 0.1% in 10,000 hr, 67% of the average stress for rupture after 100,000 hr. For heat treatable alloys, allowable stresses are 40% of the minimum strength of groove welds.This table matches B96.1 Table 9.

Table AL-5 Annular Bottom Plate Thickness Nominal

Thickness of First Shell

Course (in.)

Hydrostatic Test Stress in First Shell Course (ksi)

(as constructed) 2.0 4.0 6.0 8.0 10.0 12.0 14.0t < 0.50 ¼ ¼ ¼ ¼ ¼ ¼ 9/32

0.50 < t < 0.75 ¼ ¼ ¼ ¼ 9/32 11/32 13/320.75 < t < 1.00 ¼ ¼ ¼ 9/32 3/8 15/32 19/321.00 < t < 1.25 ¼ ¼ 9/32 3/8 ½ 5/8 ¾1.25 < t < 1.50 ¼ ¼ 3/8 15/32 5/8 ¾ 1 1/161.50 < t < 2.00 ¼ 3/8 7/16 5/8 13/16 1 1 7/32

This matches B96.1 Table 3.

Table AL-6 Minimum Shell Thickness Nominal Tank Diameter Nominal Plate Thickness

(m) (ft) (m) (in.)< 6 < 20 5 3/16

6 to <36 20 to < 120 6 1/436 to <60 120 to <200 8 5/16

> 60 >200 10 3/8Minimum shell thicknesses are

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Thickness (in.)

650 B96.1

3/16 D < 50 D < 20¼ 50 < D < 120 20 < D < 1205/16 120 < D < 200 120 < D < 2003/8 200 < DB96.1 3.3.3(b) stated that minimum thicknesses “are based on erection requirements”.

Table AL-7 Allowable Stresses for Tank Shell (For Design and Test)Allowable Stress (5) Sd for Maximum Design Temperature Not Exceeding

Alloy Temper MinimumYield

StrengthMPa (psi)

(4)

Minimum Tensile Strength

MPa (psi) (4)

40oC (100oF)

65oC (150oF)

90oC (200oF)

120oC (250oF)

150oC (300oF)

175oC (350oF)

200oC (400oF)

St

Ambient (6)

1060 all 17 (2500) 55 (8000) 14 (2,000) 14 (2,000) 13 (1,900) 12 (1,750) 10 (1,450) 7 (1,050) 6(800) 15 (2100)

1100 all 24 (3500) 76 (11000) 19 (2,800) 19 (2,800) 19 (2,800) 19 (2,700) 12 (1,750) 9 (1,350) 7 (1,000) 21 (3000)

3003 all 34 (5000) 97 (14000) 28 (4,000) 28 (4,000) 28 (4,000) 22 (3,150) 17 (2,400) 12 (1,800) 10 (1,400) 29 (4300)

Alclad 3003 all 31 (4500) 90

(13000) 25 (3,600) 25 (3,600) 25 (3,600) 20 (2,850) 15 (2,150) 11 (1,600) 9 (1,250) 26 (3800)

3004 all 59 (8500) 152 (22000) 47 (6,800) 47 (6,800) 47 (6,800) 47 (6,800) 40 (5,750) 26 (3,800) 16 (2,350) 50

(7200)Alc 3004 all 55 (8000) 145

(21000) 44 (6,400) 44 (6,400) 44 (6,400) 44 (6,400) 40 (5,750) 26 (3,800) 16 (2,350) 47 (6800)

5050 all 41 (6000) 124 (18000) 33 (4,800) 33 (4,800) 33 (4,800) 33 (4,800) 33 (4,800) 19 (2,800) 10 (1,400) 35

(5100)5052, 5652 all 66 (9500) 172

(25000) 52 (7,600) 52 (7,600) 52 (7,600) 52(7,500) 39 (5,600) 28 (4,100) 16 (2,350) 56 (8100)

5083 (1) all 124

(18000)276

(40000) 90 (13,000) 90 (13,000) 47 (6,800) 47 (6,800) 40 (5,750) 26 (3,800) 16 (2,350) 91 (13200)

5083 (2) all 117

(17000)269

(39000) 88 (12,800) 88 (12,800) 89 (12900)

5086 all 97 (14000)

241 (35000) 77 (11,200) 77 (11,100) 80

(11600)5154, 5254 all 76

(11000)207

(30000) 61 (8,800) 60 (8,700) 64 (9400)

5454 all 83 (12000)

214 (31000) 66 (9,600) 66 (9,600) 66 (9,600) 51 (7,400) 38 (5,500) 28 (4,100) 21 (3,000) 70

(10200)5456 (1) all 131

(19000)290

(42000) 96 (13900) 96 (13,900) 96 (13900)

5456 (2) all 124

(18000)283

(41000) 93 (13.500) 93 (13,500) 93 (13500)

6061, Alclad 6061 (3)

T4, T6,

T451, T651

165 (24000) 55 (8,000) 55 (8,000) 55 (8,000) 54 (7,900) 51 (7,400) 42 (6,100) 30 (4,300) 55

(8000)

(1) Thickness up to 1.500 in.(2) Thickness 1.501 to 3.000 in.(3) Temper T4 and T6 apply for thickness < 0.25 in., T451 and T651 apply for thickness > 0.25 in.(4) Strengths are for the – O temper for all alloys except 6061, Alclad 6061, and 6063.(5) The design stress shall be the lesser of 2/3 of the minimum tensile strength, 0.8 of the minimum yield strength,

the stress producing a secondary creep rate of 0.1% in 1000 hrs, or 67 % of the average stress for rupture at the end of 100000 hrs.

(6) The allowable test stress shall be the lesser of 2/3 of the minimum tensile strength or 0.85 of the minimum yield strength at ambient temperature.

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TABLE AL-8 Shell Nozzle Welding Schedule

Table AL-8 is the same as Table 3-7 with the following modifications:

Column 1 Column 5Thickness of Shell and Reinforcing

Plate t and T

Size of Fillet Weld A Nozzles Larger Than

NPS 2mm (in.) mm (in.)5 (3/16) 6 (1/4)6 (1/4) 6 (1/4)8 (5/16) 6 (1/4)10 (3/8) 6 (1/4)

11 (7/16) 6 (1/4)12.5 (1/2) 6 (1/4)14 (9/16) 6 (1/4)16 (5/8) 8 (5/16)

17 (11/16) 8 (5/16)20 (3/4) 10 (3/8)

21 (13/16) 11 (7/16)22 (7/8) 11 (7/16)

24 (15/16) 13 (1/2)25 (1) 13 (1/2)

27 (1 1/16) 14 (9/16)28 (1 1/8) 14 (9/16)30 (1 3/16) 14 (9/16)32 (1 1/4) 16 (5/8)33 (15/16) 16 (5/8)35 (1 3/8) 17 (11/16)36 (1 7/16) 17 (11/16)38 (1 1/2) 20 (3/4)40 (1 9/16) 21 (13/16)41 (1 5/8) 21 (13/16)

43 (1 11/16) 22 (7/8)45 (1 3/4) 22 (7/8)

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Figure AL-1 Cover Plate Thickness for Shell Manholes and Cleanout Fittingssame as B96.1 Figure 8

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Figure AL-2 Flange Plate Thickness for Shell Manholes and Cleanout Fittings

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For Figures AL-1 and AL-2, disregard the notes on the Figures above and use:G = specific gravity of liquid that determines the shell thickness H = height of tank above centerline of manhole (ft)f = allowable tensile stress from Table AL-7 at the temperature coincident with G, psiNote: (1) the minimum cover plate thickness shall be the maximum of case A or B values.

Figure AL-3 Bottom Reinforcing Plate Thickness for Cleanout Fittings

For Figure AL-3, disregard notes and use: G = specific gravity of the liquid that determines shell thickness; H = height of tank (ft) Note: the bottom reinforcing plate shall be the same alloy and temper as the bottom shell plate.

Figure AL-4 Stresses in Roof Plates (same as B96.1 Figure 12)

For Figure AL-4, disregard the notes above and use the following:

L = maximum rafter spacing tr = thickness of roof

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