7/30/2019 Cck Vnt Tank Cal Roof

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ROOF PLATE

Type of Roof : Supported Cone Roof

Cone angl e [Sl ope = 1: 6] 9. 5 degr ee

Cor r osi on al l owance f or Roof pl at e CAr 3. 0 mm

Mi n. t hi ckness as per Cl ause 5. 10. 2. 2 t r mi n 5. 00 mm

Mi n. t hi ckness + CA t r 5. 00 mm

Pr ovi ded Roof pl at e t hi ckness t r pr o 5.0 mm

Sel f support i ng cone r oof desi gn per API 650 cl . 5. 10. 5

B = 7.0 mm

I nsu Thk - mm

Den - Kg/ m3

Est Wt . I nsul ati on at Roof - Kg.

- KN

Est Wt . Handr ai l Pl atf orm & Gr ati ng t a t op Roof - Kg.

- KN

Angl e of cone el ement s t o hor i zont al O 9. 5 Deg.

Nor mi nal dai met er of t he t ank shel l D 960 mm

Roof dai met er Dr 974 mm

Roof devel oped r ad Rd 494 mm

Roof devel oped ar ea Ra 0. 77 M2

Roof cor r osi on al l owance Ca 3. 00 mm

Act ual r oof t hi ckness t r pr o 5. 0 mm

Roof met al wei ght ( New) 31 Kg.

0. 30 KN

t = Gr eat er of l oad combi nati on( e)( 1) and( e)( 2) of Appendi x R

LOAD ( e) ( 1) = DL+( Lr OR S)+0. 4Pe

LOAD ( e) ( 2) = DL+Pe+0. 4(Lr OR S)

Dead Load Dl 0. 39 Kpa

Mi n. Roof Li ve Load Lr 1. 20 Kpa

Speci f i ed ext er nal pr esur e Pe 0. 49 Kpa

Load ( e) ( 1) = 1. 79 Kpa

Load ( e) ( 2) = 1. 37 Kpa

So t 1. 79 Kpa

Mi ni mum t hi ckness = ( D/ 4. 8 SI N( DEG) ) *( T/ 2. 2) 0. 5+C. A t mi n 4. 093 mm

Pr ovi ded Roof pl at e t hi ckness t r pr o 5.0 mm

So Check t r pro >= t mi n OK

Design Calculations

7/30/2019 Cck Vnt Tank Cal Roof

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Rev. A

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CHECK POI NT AS PER API 650- 5. 10. 5. 1

Deg =9. 5 OKMi ni mumpr ovi ded roof pl at ethi ckness > 5 mm. OK

Provi ded roof pl ate t hi ckness >= Mi n. t hi ckness OK

Roof design is comply with API650-5.10.5.1

Roof to shell junction summary

Desi gn pr essur e 49. 05 Kpa

Roof cor r osi on al l owance 3. 00 mm

J unct i on t ype Top angl e

Descr i pt i on ( sel ect ed per 5. 1. 5. 9) 50*50*5 Used 50*50*5

Mat er ai l spec J I S G3110 SS400

Top angl e yi el d st r engt h 245 Mpa

Yi el d st r ength r educt i on f act or ( Appendi x M t abl e M1a) 0. 88Thi ckness of angl e l eg ta 5 mm

Natural axi s of t op angl e (per J I S G3192) 14. 1 mm

Angl e sect i on area (per J I S G3192) 480. 2 mm2

Roof pl at e mat er i al A240- GR- 316L

Roof pl at e yi el d st r engt h 170 Mpa

Lowest mi n. yi el d st r engt h( mul t i pl i ed by r educt i on f act or Fy 150 Mpa

Roof t hi ckness ( New) th 5. 0 mm

Roof t hi ckness ( Cor r oded) t h( cr ) 2. 0 mm

Angl e of cone el ement t o t he hor i zont al o 9. 5 Deg.

Nomi nal di amet er of t he t ank shel l D 960 mm

I nsi de r adi us t ank shel l ( New) Rc 480 mm

I nsi de r adi us t ank shel l ( Cor r oded) Rc( Cr ) 483 mmTop shel l cour se t hi ckness ( new) t c 5. 00 mm

Top shel l cour se t hi ckness ( Cor r oded) t c( Cr ) 2. 00 mm

API-650-appendix F,Figure 4-2 Detail b

A( New) = Ar ea r esi st i ng compressi ve f orce( New)

A( new) = ( Wh*t h)+( Wc*t c) +( Top angl e sect i onal area up t o Le)

Wh( New) = 0. 3( Rc/ Si n( o)) *t h) 0. 5 or 300 whi chever i s l ess

0. 3( Rc/ si n( o) ) *t h) 0. 5 36. 2 mm

So Wh 36. 2 mm

Wc = 0. 6*( Rc*t c) 0. 5 29. 4 mm

Le shel l be l i mi t ed t o 250*( Fy) 0. 5

250*t a/ ( ( Fy) 0. 5) 102. 2 mm

Le i s more t han t op angl e f l ange so use f ul l t op angl e sect i on area up t o l eSo Ar ea r esi st i ng compr essi ve f or ce ( New) A( New) 430. 0 mm

2

A( Cr ) = Ar ea r esi st i ng compr essi ve f orce( Corr oded)

A( Cr ) = ( Wh( Cr ) *t h( Cr ) ) +( Wc( Cr ) *t c( Cr ) ) +( Top angl e secti onal area up t o Le)

Wh( Cr ) = 0. 3( Rc( Cr ) / Si n( o) ) *t h( Cr ) ) 0. 5 or 300 whi chever i s l ess

0. 3( Rc( Cr ) / si n( o) ) *t h( Cr ) ) 0. 5 23. 0 mm

So Wh( Cr ) 23. 0 mm

Wc( Cr ) = 0. 6*( Rc( Cr ) *t c( Cr ) ) 0. 5 18. 6 mm

So Ar ea r esi st i ng compr essi ve f or ce ( Cor r oded) A( Cr ) 185. 40 mm2

Ar ea r equi r ed by 5. 10. 5. 2 = T*D 2/ 0. 9504si n(o) ( New)

Ar ea r equi r ed by 5. 10. 5. 2 ( Corr oded)

Ar ea r equi r ed by App. F. 5. 1 =200D 2(Pi - 0. 08t h) / Fy(t an( 0))

Design Calculations