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API-650 DESIGN3 methods of calculation for the shell thicknesses:

1-foot method(API 650 Paragraph 5.6.3):The thicknesses required

are calculated at design points (0.3 m or 1 ft) above the bottom of

each shell course. This method shall not be used for tanks larger than61 m or 00ft.

Variable -Design Point Method(API 650 paragraph 5.6.4):The

thicknesses are calculated at design points that results in thecalculated stresses being relativel! close to the actual circumferential

shall stresses. The limitation for using this method is given inparagraph ".6.#.1

Aendi! A(optional design basis for small tank) (API 650 paragraph

1.1.7):This method is applied for relativel! small tanks in $hich thecomponents have a ma%imum nominal thickness of 13 mm or 0." in.The recommendations for using this method are listed in the

paragraph &.1.1

The local loads due to no''le are calculated according to & 6"0 &ppendi% .

The &ppendi% * is not implemented and consequentl! the temperature above +3,- could not be allo$ed. &

message is displa!ed in this case.

The stresses calculated b! &uto /essel are based on the ield strentgh at temperature : &uto /esselstresses are lo$er than & stresses issued from Table "a and "b for these materials $hen temperature is lessor equal to +3 ,-The input of the volume is optional. nstead of input the volume2 !ou can directl! define the diameter and the

height of the tank.The volume is input in m3 ( units) and in 4il 5arrel ( units).7hen the volume is input2 a diameter and a height are calculated. These values correspond to the volumecalculated at the 8Top of shell height8 and not to the ma%imum capacit! sho$n of 9igure "# in the paragraph "..6of & 6"0.iameter and ;eight ma! be changed no$ or later in modif!ing the shells dimensions.

7hen creating a tank2 the ma%imum plate $idth or the ser plate $idthallo$ the splitting of the height to obtain the number of courses.

To input an annular bottom plate2 input in the 8&nchor8 screen the follo$ing informations :7idth of annular plate (dimension &)Thickness of annular plate (5ase plate Thickness -)%ternal radial $idth (5aseplates option

Technical nquiries ?equired rocedures

eismic esign for Tank urchaser>s option

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9 esign of tank for small internal pressure ?equirements

@ se of @e$s material not identified ?equirements

&llo$able e%ternal load on tank shell opening urchaser>s option

/ esign in %ternal ressure urchaser>s option