UNI21000236_EEN

21
8/12/2019 UNI21000236_EEN http://slidepdf.com/reader/full/uni21000236een 1/21  © UNI – Ente Nazionale Italiano di Unificazione Pag. 1 di 1  ERRATA CORRIGE N° 1 alla versione in lingua inglese DEL 7 novembre 2013 NORMA UNI EN 13445-3 (novembre 2012) TITOLO Recipienti a pressione non esposti a fiamma – Parte 3: Progettazione Punto della norma Pagina Oggetto della modifica Modifica - I Relazioni internazionali Sostituire “il 27 luglio 2011 e il 25 luglio 2012” con “il 27 luglio 2011, il 25 luglio 2012 e il 31 luglio 2013” - II Premessa nazionale Sostituire “del 27 luglio 2011 e del 25 luglio 2012” con “del 27 luglio 2011, del 25 luglio 2012 e del 31 luglio 2013” - II Dopo pagina II Sostituire le pagine 6, 60, 100, 165, 166, 167, 168, 197, 199, 210, 211, 241, 242, 262, 418, 576, 579, 581, 594, 832a della EN 13445- 3:2009 con quelle in allegato Documenti allegati: Pagina 6, 60, 100, 165, 166, 167, 168, 197, 199, 210, 211, 241, 242, 262, 418, 576, 579, 581, 594 e 832a della EN 13445-3:2009

Transcript of UNI21000236_EEN

Page 1: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 1/21

 

© UNI – Ente Nazionale Italiano di Unificazione Pag. 1 di 1

 

ERRATA CORRIGE N° 1 alla versione in lingua inglese

DEL 7 novembre 2013

NORMA UNI EN 13445-3 (novembre 2012)

TITOLO Recipienti a pressione non esposti a fiamma – Parte 3:Progettazione

Punto dellanorma

Pagina Oggetto dellamodifica

Modifica

- I Relazioniinternazionali

Sostituire “il 27 luglio 2011 e il 25 luglio 2012” con “il 27 luglio 2011, il25 luglio 2012 e il 31 luglio 2013”

- II Premessanazionale

Sostituire “del 27 luglio 2011 e del 25 luglio 2012” con “del 27 luglio2011, del 25 luglio 2012 e del 31 luglio 2013”

- II Dopo pagina II Sostituire le pagine 6, 60, 100, 165, 166, 167, 168, 197, 199, 210,211, 241, 242, 262, 418, 576, 579, 581, 594, 832a della EN 13445-3:2009 con quelle in allegato

Documenti allegati:

Pagina 6, 60, 100, 165, 166, 167, 168, 197, 199, 210, 211, 241, 242, 262, 418, 576, 579, 581, 594 e 832adella EN 13445-3:2009

Page 2: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 2/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

6

Foreword

This document (EN 13445-3:2009) has been prepared by Technical Committee CEN/TC 54 “Unfired pressurevessels”, the secretariat of which is held by BSI.

This European Standard shall be given the status of a national standard, either by publication of an identical text orby endorsement, at the latest by December 2009, and conflicting national standards shall be withdrawn at the latestby December 2009.

 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.

This document has been prepared under a mandate given to CEN by the European Commission and the EuropeanFree Trade Association, and supports essential requirements of EU Directive(s).

For relationship with EU Directive(s), see informative annex ZA, which is an integral part of this document.

This European Standard consists of the following Parts:

    Part 1: General .

    Part 2: Materials.

    Part 3: Design.

    Part 4: Fabrication.

    Part 5: Inspection and testing .

    Part 6: Requirements for the design and fabrication of pressure vessels and pressure parts constructed fromspheroidal graphite cast iron.

    CR 13445-7, Unfired pressure vessels — Part 7: Guidance on the use of conformity assessment procedures .

    Part 8:  Additional requirements for pressure vessels of aluminium and aluminium alloys. 

    CEN/TR 13445-9, Unfired pressure vessels — Part 9: Conformance of EN 13445 series to ISO 16528  

This document supersedes EN 13445-3:2002. This new edition incorporates the Amendments which have beenapproved previously by CEN members, and the corrected pages up to Issue 36 without any further technicalcharge. Annex Y to EN 13445-1:2009 and Annex Y to this Part provides details of significant technical changesbetween this European Standard and the previous edition.

 Amendments to this new edition may be issued from time to time and then used immediately as alternatives torules contained herein. It is intended to deliver a new Issue of EN 13445:2009 each year, consolidating these Amendments and including other identified corrections. Issue 5 (2013-07) includes the corrected pages listed in Annex Y.

 According to the CEN/CENELEC Internal Regulations, the national standards organizations of the followingcountries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic,Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland,

Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia,Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

UNI EN 13445-3:2012

Page 3: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 3/21

Page 4: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 4/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

100

Where a small opening lies beyond the distance w p defined in 9.7.3, no reinforcement check is necessary. Where itlies within this distance, the reinforcement shall be in accordance with equation (9.5-7) or (9.5-11) as appropriate.However the distance w  between small opening and shell discontinuity shall respect the minimum value w min as

required in 9.7.1.

9.5.2.3 General requirements for reinforcement

9.5.2.3.1 Reinforcing pads

For cases where a reinforcing pad contributes to the reinforcement (see Figures 9.4-3, 9.4-4, 9.4-10):

    reinforcing plates shall be fitted in close contact with the shell.

    the width of a reinforcing plate  l'  p  to be considered as contributing to reinforcement is given by

);min('

 p so p   l l l     (9.5-19)

    the value of   e p used for the calculation of   Af  p  shall not exceed the following 

);min( ,,   sc pa p   eee   (9.5-20)

furthermore the analysis thickness of the reinforcing pad shall meet the following condition

ea,p     1.5 ea,s (9.5-21)

   ea,p  and  l  p are dimensions of reinforcing pads used in equations for openings that may be reinforced also byreinforcing pads; if reinforcing pad is not present then the values  ea,p  and  l  p shall be put equal to zero. If thereinforcing pad is contributing to reinforcement then, for all cases:

 p p p el  Af    '   (9.5-22)

9.5.2.3.2 Joint coefficient

9.5.2.3.2.1 Opening intersecting with a shell governing weld

If an opening intersects with a shell governing weld (see definition in 5.6), the value  f s  in equation (9.5-7,11,13 and16) for the shell material shall be replaced by  f s·z, where z is the joint coefficient of the shell.

9.5.2.3.2.2 Nozzle with a longitudinal weld

If a nozzle has a longitudinal weld having a weld joint factor z, the value   f b  for the nozzle material  shall be

replaced by  f b  z except for openings in cylindrical or conical shells if the angle  as defined in subclause 9.3.2 isgreater than 45°.

9.5.2.3.2.3 Reinforcing pad with a weld

If a reinforcing pad has a weld having a weld joint factor z, the value  f  p  for the pad material shall be replaced by f  p    z except for openings in cylindrical or conical shells if the angle between the pad weld and the shell generatrixis greater than 45°.

9.5.2.3.3 Fillet weld areas for compensation

For all cases:

    Af w  is the area of any welds connecting together the different components (shell to nozzle, shell to  reinforcingring or reinforcing plate) which is located within length  l’ s  on the shell (see 9.5.2.4.2) and lengths  l’ b  and  l’ bi  on the nozzle (see 9.5.2.4.4.1). Areas of welds already included in other  areas, e.g. Af s, Af r , Af  p or  Af b, shall be

omitted from Af w  (see Figures 9.4-6 and 9.4-10).

UNI EN 13445-3:2012

Page 5: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 5/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

165

0,5

0,6

0,7

0,8

0,9

1 1,5 2 2,5 3 3,5 4 4,5 5

0,100,200,25

0,300,35

0,40

0,45

0,50

0,60

0,70

0,80

0,90

1,00

1,251,50

2,00

h  = h

l  Bg 00

0,908920

β F

 g1/ g0  

Figure 11.5-4 — Value of  F for = 0,3 (integral method factor)

0

0,1

0,2

0,3

0,5

0,4

0,6

1 1,5 2 2,5 3 53,5 4 4,5

 g  / g1 0

0,100,120,140,160,180,20

0,250,300,35

0,400,450,50

0,600,700,800,901,001,251,502,00

h  = h

l  Bg0 0

0,550103

β V

 

Figure 11.5-5 — Value of  v for = 0,3 (integral method factor)

UNI EN 13445-3:2012

Page 6: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 6/21

Page 7: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 7/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

167

The radial stress in flange and longitudinal stress in hub are

0Hr          (11.5-36)

c) Loose hubbed flange method

  FL and   VL  are given by Equations 11.5-37 and 11.5-38 or are found from Figures 11.5-7 and 11.5-8

respectively :

 A

v

 A AC 

 AC 

 AC 

  34/1

2

242118

FL

1

)1(3

360

59

210

23

84

1121

6

3

 

  

   

 

  

   

 

  

   

 

  

   

  (11.5-37)

where A, C , C 18, C 21 and C 24 are coefficients obtained from Equations in 11.5.4.1.2.

   is the Poisson's ratio

3

4/12

182124

VL

113

2

3

54

1

 AC 

v

C C C 

  

 

  (11.5-38)

where A, C , C 18, C 21 and C 24 are coefficients obtained from Equations in 11.5.4.1.2.

   is the Poisson's ratio

Figure 11.5-7 — Value of FL for   = 0,3 (loose hub flange factor)

UNI EN 13445-3:2012

Page 8: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 8/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

168

0,010,020,030,040,080,1

0,2

0,20,30,4

0,60,8

1

2

3468

10

2030406080

100

2,00

1,50

1,00

0,900,80

0,70

0,60

0,500,450,40

0,35

0,30

0,25

0,200,180,160,14

0,12

0,10

1,0 1,5 2,0 3,0 4,0 5,0

 g  / g1 0

β VL

h  = h

l  Bg0 0

 

Figure 11.5-8 — Value of  VL for = 0,3 (loose hub flange factor)

200U

VL3

0T

0FL

g l 

e

l e

  

  

  

      (11.5-39)

The longitudinal hub stress:

2

1

Hg 

       (11.5-40)

The radial flange stress:

0

2

0FLr 

)(1,333

l e

M l e

 

      (11.5-41)

The tangential flange stress:

1

12

2

r 2

Y

e

M  

       (11.5-42)

11.5.4.1.2 Coefficients for flange stresses calculations

10

1 g 

g  A   (11.5-43)

4

0

2)1(48

 

 

 

 

hv C    (11.5-44)

UNI EN 13445-3:2012

Page 9: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 9/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

197

13.4.2 Conditions of applicability

13.4.2.1 Tubesheet

The tubesheet shall comply with the following conditions of applicability.

a) The tubesheet shall be flat, circular and of uniform thickness.

b) A local reduction of thickness at the periphery of the tubesheet for a gasket groove or a relief groove is

permitted, provided that the remaining analysis thickness, ea,p , is at least equal to 0,8 times the assumed

thickness, e , of the tubesheet (see Figure 13.4.2-1):

ee pa, 8,0 (13.4.2-1)

The radius shall be not less than 5 mm and not less than 20 % of the adjacent shell thickness. The

requirement for the remaining analysis thickness given above shall apply only if the ratio of the outsidediameter to inside diameter of the adjacent shell is larger than 1,2.

a) Configuration a b) Configuration b and e

c) Configuration d d) Configuration c and f

Figure 13.4.2-1 Local reduction of thickness at tubesheet periphery

c) When the tubesheet is extended as a flange, the flange extension thickness shall be calculated according to:

   13.10 if the gasket is narrow (configurations b, d2, e);

   13.11 if the gasket is full face (configurations b', '2d , e').

d) Unless satisfactory experience has been demonstrated with thinner tubesheets, the following conditions shallbe met when the tubes are expanded into the tubesheet:

— when d t    25 mm:

UNI EN 13445-3:2012

Page 10: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 10/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

199

E is the elastic modulus of tubesheet material at design temperature;

E c   is the elastic modulus of channel material at design temperature;

E s   is the elastic modulus of shell material at design temperature;

*E    is the effective elastic modulus of the tubesheet at design temperature, see 13.7;

e  is the assumed thickness of the tubesheet (see Figure 13.7.3-3);

ec   is the channel thickness (see Figure 13.4.1-1);

es   is the shell thickness (see Figure 13.4.1-1);

F   is a coefficient given in 13.4.4.3d;

f is the nominal design stress of tubesheet material at design temperature;

f c   is the nominal design stress of channel material at design temperature;

f s   is the nominal design stress of shell material at design temperature;

1G   is the diameter of the midpoint of contact face between flange and tubesheet, given by equation (11.5-97);

Gc   is the diameter of channel gasket load reaction (see clause 11);

Gs   is the diameter of shell gasket load reaction (see clause 11); 

hg'   is the effective depth of tube-side pass partition groove, see 13.7;

K   is the tubesheet diameter ratio given by equation (13.4.4-6);

ck is the edge moment per unit length required to rotate the channel edge through unit angle, given by

Table 13.4.4-1;

sk    is the edge moment per unit length required to rotate the shell edge through unit angle, given by

Table 13.4.4-1;

oM    is the moment [Nmm/mm] acting at centre of tubesheet, given by equation (13.4.5-7);

PM    is the moment [Nmm/mm] acting at periphery of tubesheet, given by equation (13.4.5-6);

PcM    is the moment [Nmm/mm] acting on the unperforated tubesheet rim due to pressure in the integral channel,

given by Table 13.4.4-1;

PsM    is the moment [Nmm/mm] acting on the unperforated tubesheet rim due to pressure in the integral shell,

given by Table 13.4.4-1;

TSM    is the moment [Nmm/mm] due to pressures sP   and tP   acting on the unperforated tubesheet rim, given by

equation (13.4.4-5);

M * is the moment [Nmm/mm] acting on the unperforated tubesheet rim (see 13.4.5.1);

P s   is the shell-side calculation pressure. In case of vacuum, this shall be taken as negative;

UNI EN 13445-3:2012

Page 11: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 11/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

210

c) 13.5.2 to 13.5.9 apply to configuration a (where the tubesheet is integral) and to configurations b, c and dwhere the gasketed tubesheet has a narrow gasket.

13.5.10 outlines how to use these rules for configuration b' and d' where the gasketed tubesheet has a fullface gasket.

13.5.9 enables to cover shell having a different thickness, or a different material, adjacent to the tubesheet

when integral with the tubesheet (configurations a, b, c).

a) Configuration a b) Configuration b

Tubesheet integral with shell and channel Tubesheet integral with shell and gasketedwith channel, extended as a flange

c) Configuration c d) Configuration d

Tubesheet integral with shell and gasketedwith channel, not extended as a flange

Tubesheet gasketed with shell and channel,not extended as a flange 

Figure 13.5.1-2 Fixed tubesheet configurations

13.5.2 Conditions of applicability

13.5.2.1 Tubesheets

The tubesheets shall comply with the following conditions of applicability:

a) The two tubesheets shall be flat, circular and identical (i.e. same uniform thickness, same material, sameconnection with shell and channel);

b) A local reduction of thickness at the periphery of the tubesheet for a gasket groove or a relief groove is

permitted, provided that the remaining analysis thickness, ea,p , is at least equal to 0,8 times the assumed

thickness, e, of the tubesheet (see Figure 13.5.2-1):

UNI EN 13445-3:2012

Page 12: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 12/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

211

ee  8,0 pa,   (13.5.2-1)

The radius shall be not less than 5 mm and not less than 20 % of the adjacent shell thickness. Therequirement for the remaining analysis thickness given above shall apply only if the ratio of the outsidediameter to inside diameter of the adjacent shell is larger than 1,2.

a) Configuration a b) Configuration b

c) Configuration c d) Configuration d

Figure 13.5.2-1 Local reduction of thickness at tubesheet periphery

c) When the tubesheets are extended as a flange, the flange extension thickness, shall be calculated accordingto:

    13.10 if the gasket is narrow (configuration b),

    13.11 if the gasket is full face (configuration b').

d) Unless satisfactory experience has been demonstrated with thinner tubesheets, the following conditions shallbe met when the tubes are expanded into the tubesheet:

    when d t    25 mm:

ae 0,75 d t(13.5.2-2)

    when 25 mm d t    30 mm:

ae 22 mm(13.5.2-3)

    when 30 mm d t    40 mm:

ae 25 mm(13.5.2-4)

UNI EN 13445-3:2012

Page 13: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 13/21

Page 14: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 14/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

242

a) Configuration A

b) Configuration B  c) Configuration C 

Figure 13.6.2-2 — Local reduction of thickness at floating tubesheet periphery

d) When the tubesheets are extended as a flange, the flange extension thickness, shall be calculated accordingto:

    13.10 if the gasket is narrow (configurations b, d, e)

    13.11 if the gasket is full face (configurations b', d', e')

e) Unless satisfactory experience has been demonstrated with thinner tubesheets, the following conditions shallbe met when the tubes are expanded into the tubesheet:

    when d t    25 mm:

ae 0,75 td  (13.6.2-2)

    when 25 mm d t    30 mm:

ae 22 mm(13.6.2-3)

    when 30 mm d t    40 mm:

ae 25 mm(13.6.2-4)

    when 40 mm d t    50 mm:

ae 30 mm(13.6.2-5)

f) The tubesheets shall be uniformly perforated over a nominally circular area of diameter oD , in either

equilateral triangular or square pattern.

UNI EN 13445-3:2012

Page 15: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 15/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

262

c) These values of  jt,f   can be increased up to the value f t  if the tube-to-tubesheet joining procedure is approved

and checked with pull-out tests.

13.9 Maximum permissible longitudinal compressive stress for tubes

13.9.1 Purpose

This clause provides rules to determine the maximum permissible longitudinal compressive stress in the tubes ofexchangers with a pair of tubesheets joined by a bundle of straight tubes to cover their failure through elastic

instability and buckling under the effect of an axial compressive force and pressures P t  and P s .

13.9.2 Symbols

b0   is the tube imperfection factor;

td    is the nominal outside diameter of tubes (see Figure 13.7.3-3);

tE is the elastic modulus of tube material at design temperature;

te is the nominal tube wall thickness (see Figure 13.7.3-3);

f t,bk   is the maximum permissible buckling stress of tubes;

l t,bk   is the buckling length of tubes;

P s   is the shell-side calculation pressure. In case of vacuum, this shall be taken as negative;

P t   is the tube-side calculation pressure. In case of vacuum, this shall be taken as negative;

0,2/Tp R is the proof strength of tube material at design temperature;

 x is the safety factor on tube buckling;

 t,cr   is the Euler critical stress for tubes;

 t,p   is the factor for pressure effect on tubes;

Symbols l l l l l  1 1 2 2 3, ' , , '  and are defined on Figure 13.9.3-1.

13.9.3 Determination of maximum permissible buckling stress

a) The buckling length of tubes, l t,bk , is given by:

    if some tubes are not supported by any baffle-plate:

bkt,l    0 5, L (13.9.3-1)

    if all the tubes are supported by at least one baffle-plate (see Figure 13.9.3-1):

  l L l l l l l  t,bk 1 1 2 2  ; min , ; max , ; , ' ; , ; , '0 5 0 7 0 7 0 7 0 7 3 (13.9.3-2)

UNI EN 13445-3:2012

Page 16: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 16/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

418

5) Check that:

14

allc,

c

maxe,

e

 

e

DP 

 

P  a

e

  (16.14-14)

6) If both inequalities are satisfied then the design is satisfactory; if not ea should be increased and the

calculation repeated;

16.14.8 Compressive stress limits

16.14.8.1 Calculation

The following procedure shall be used to find the permissible longitudinal compressive stress in a cylindrical shell.

The method for measuring tolerance is given below (see 16.14.8.2). The maximum value ofI 

w  shall not exceed

0,02.

1) calculate

eE K 

e

a21,1  (16.14-15)

2) if D/ea  424 then

  

0 83

10 0 005

,

, , /D ea

  (16.14-16)

if D/ea > 424 then

  

0 7

01 0 005

,

, , /D ea

  (16.14-17)

3) if the maximum value ofI 

w  lies between 0,01 and 0,02 the value of  is reduced by the factor

(1,5 - 50I 

w ).

4) if  K  < 0,5 then:

0 75

15

,

,

 K   (16.14-18)

and if  K   0,5 then

5,1

4123,00,1

6,0 K  

  (16.14-19)

NOTE The safety factor 1,5 in the nominator is valid for operation conditions. It should be adapted for testing orexceptional conditions in accordance with clause 6.

UNI EN 13445-3:2012

Page 17: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 17/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

576

B.9.4 Creep Rupture (CR) 

B.9.4.1 Principle

For each creep load case, the design value of an action, or of a combination of actions, shall be carried by thedesign model with

    linear-elastic ideal-plastic constitutive law,

    von Mises' yield condition (maximum distortion energy hypothesis) and associated flow rule

    material strength parameter RM  and a partial safety factor R   as specified in Tables B.9-2 and B.9-3.

    proportional increase of all actions and a stress-free initial state

with the maximum absolute value of the principal structural strains being less than 5 %.

With the exception of cases where deformation has a weakening effect, see B.7.1, first-order-theory shall be used;where deformation has a weakening effect, geometrical non-linear effects shall be taken into account.

B.9.4.2 Application rule: Lower bound limit approach

If it can be shown that any lower bound limit value of the action or combination of actions, determined with thedesign model specified in the principle, is reached without violation of the strain limit, the principle is fulfilled, if thedesign value of the action or combination of actions does not exceed that lower bound limit value.

B.9.4.3 Design Checks

a) Design checks are required for normal operating load cases only

b) Partial safety factors for actions shall be as given in Table B.9-1

Table B.9-1: Partial safety factors for actions for CR load cases

Action Condition Partial safety factor

Permanent For actions with an unfavourable effect 2,1G   

Permanent For actions with a favourable effect 8,0G   

Variable For unbounded variable actions 5,1Q   

Variable For bounded variable actions and limit values 0,1Q   

Pressure 2,1P   

Temperature a 0,1R a

It may be necessary to include also effects caused by constrained temperature induced displacements in a CR-DC, e.g. when part-models are used and displacements in one model are imposed on the other model.

c) Combination rules shall be as follows:

    All permanent actions shall be included in each load case.

    Each pressure action shall be combined with the most unfavourable variable action.

UNI EN 13445-3:2012

Page 18: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 18/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

579

    von Mises' yield condition (maximum distortion energy hypothesis)

    material strength parameters and partial safety factors as described in B.9.5.3.3.2 below

and

    for proportional increase of all actions, with the exception of temperature, which shall be time-independent, and

    a stress free initial state.

B.9.5.3.3.2 Material strength parameters and partial safety factors

Material strength parameters shall be as in Table B.9-2, but

    partial safety factors  R  shall be equal to 1,0,

    the reference time shall be the (sufficiently long) interval duration)(k 

t  , see B.9.5.3.3.1

NOTE 1 For structures of more than one material the material strength parameters, and their design values, will be space-dependent.

NOTE 2 For structures of one material, the material strength parameters, and their design values, may be space-dependentor space-independent, depending on the choice of the creep design temperature.

B.9.5.3.3.3 Determination of the (strain limiting) limit action )(u

k  A .

For each interval, of duration)(k 

t  , in which the calculation temperature is in the creep range, the maximum value

of the action, or the combination of actions, shall be determined which can be carried by the design model with

    linear-elastic ideal-plastic constitutive law,

    von Mises' yield condition (maximum distortion energy hypothesis) and associated flow rule,

    material strength parameters and partial safety factors as in B.9.5.3.3.2

and for

    proportional increase of all actions, with the exception of temperature, which shall be time-independent,

    stress free initial state,

with a maximum absolute value of the principal structural strains less than 5 %.

B.9.5.3.3.4 Reference stress

For each of these intervals, of duration)(k 

t  , the design reference stress is given by

)(u/

)(d

)(d

)(e/))(

e)(

u(13,01)(ref 

k  Ak 

RM k 

 Ak  Ak  Ak  Ak 

    (B.9-2)

UNI EN 13445-3:2012

Page 19: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 19/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

581

B.9.5.4.2 Action cycles with negligible creep

 Action cycles, which interrupt long creep periods, are considered to be of negligible creep, if the maximum duration

of calculation temperatures in the creep range is less than 100 h.

B.9.5.4.3 Action cycles without plastification

 Action cycles, which interrupt long creep periods, are considered to be without plastification, if the maximum vonMises' equivalent stress of the response of the model, described below, to the cyclic actions and with initialconditions, described below, does not exceed the short-term design material strength parameter, described below:

a) The constitutive law of the model shall be linear-elastic with material parameters for a temperature given inB.7.5.2.

b) The initial stress distribution shall be the one obtained like in the determination of the limit action B.9.5.3.3.3 fora reference time, required for the determination of the material strength parameters in B.9.5.3.3.2 given by the

total creep period.

c) The short-term design material strength parameter, with which the maximum equivalent stress is compared,shall be the minimum specified values of

  cp0,2/T R   for ferritic steels,

  cp1,0/T R  for austenitic steels,

where cT   is the respective temperature at each point and each time.

B.9.5.5 Design checks

 Actions, combination rules, reference temperature and reference time for creep periods, shall be as for the CR-DC,in B.9.4.3, but all partial safety factors for actions shall be equal to 1,0.

B.9.6 Creep and cyclic fatigue (CFI)

For each point of the structure, the sum of the design value of the creep damage indicator, see B.9.5.3, and thedesign value of the fatigue damage indicator (for cyclic actions), see B.8.5, shall not exceed unity.

UNI EN 13445-3:2012

Page 20: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 20/21

EN 13445-3:2009 (E)Issue 5 (2013-07)

594

Key

1  shell

2  nozzle

3  nozzle base region

4  thickness transition regions

5  limits of local primary membrane stress region

NOTE This figure shows the case of an opening with nozzle in a cylindrical shell. It also applies to the case of an openingwith nozzle in a spherical, conical or toroidal shell or in the central region of a dished end (R m  is the circumferential mean

curvature radius). It applies as well to the case of an opening without nozzle (for this case ea,n   0). It does not apply to an

opening in a flat end or a flat wall; in such cases, see footnote11)

 to Table C-2.

When the level of stress acting in the vicinity of the opening is such that a local primary membrane stress regionoccurs, the extent of this region, measured taking account of both sides of the nozzle-shell discontinuity, shall

satisfy the condition:

2

na,msa,mns

er eR l l 

  (C.5-2)

Possible thickness transitions which may occur between a reinforced part and an unreinforced part of the nozzleand/or of the shell do not usually involve local primary membrane stress regions.

Where, for particular geometrical or loading arrangements, such regions occur in the vicinity of these transitions,the conditions in C.7.2 relating to the spacing between adjacent regions of local primary membrane stresses shallbe met, particularly as regards the spacing from the adjacent local primary membrane region at nozzle base.

Figure C-4 — Opening in a shell

UNI EN 13445-3:2012

Page 21: UNI21000236_EEN

8/12/2019 UNI21000236_EEN

http://slidepdf.com/reader/full/uni21000236een 21/21

EN 13445-3:2009 (E)Issue 4 (2012-07)

 Y.2 List of corrected pages of Issue 2 (2010-07)

Pages 5, 6, 15, 16, 50, 72, 88, 89, 140, 158, 175, 221, 279, 298, 321, 332, 385, 465, 497, 500, 559, 608, 610, 614,645, 652, 707, 752, 758, 770, 773, 781, 828, 832, 832a.

 Y.3 List of corrected pages of Issue 3 (2011-07)

Pages 6, 11, 13, 18, 19, 31, 32, 36, 40, 44, 45, 48, 65, 67, 69, 73 to 76, 84, 114, 115, 137, 138, 141, 144, 161, 167,169, 170, 173, 176, 178, 180, 181, 182, 190, 198, 199, 211, 212, 242, 243, 258, 279, 282, 292, 300, 302, 306, 308,309, 310, 319, 327, 332, 337, 340, 346, 371, 377, 384, 391, 397, 400, 406 à 409, 415, 418, 430, 470, 503, 505,533, 554, 618, 632, 644, 654 to 658, 749, 751, 768, 788, 808, 814, 832a.

 Y.4 List of corrected pages of Issue 4 (2012-07)

Pages 4, 6, 48, 72, 309, 331, 332, 336, 359, 360, 421, 422, 424, 424a to 424d, 425, 434, 435, 436, 437, 438, 457,488, 497, 498, 507, 511, 527, 529, 530, 531, 532, 533, 534, 536, 537, 538, 539, 542, 543, 546, 547, 548, 549, 550,585, 588, 600, 637, 655, 656, 667, 781, 785, 791, 808, 832a.

 Y.5 List of corrected pages of Issue 5 (2013-07)

Pages 6, 60, 100, 165, 166, 167, 168, 197, 199, 210, 211, 241, 242 262, 418, 576, 579, 581, 594, 832a.