# EN 13445-3:2014/A3:2017

(Amendment)## Unfired pressure vessels - Part 3: Design

## Unfired pressure vessels - Part 3: Design

This Part of this European Standard specifies requirements for the design of unfired pressure vessels covered by EN 13445-1:2009 and constructed of steels in accordance with EN 13445-2:2009. EN 13445-5:2009, Annex C specifies requirements for the design of access and inspection openings, closing mechanisms and special locking elements. NOTE This Part applies to design of vessels before putting into service. It may be used for in service calculation or analysis subject to appropriate adjustment.

## Unbefeuerte Druckbehälter - Teil 3: Konstruktion

Dieser Teil 3 der Europäischen Norm legt die Anforderungen an die Konstruktion von unbefeuerten Druckbehältern

nach EN 13445-1:2014 und hergestellt aus Stählen nach EN 13445-2:2014 fest.

EN 13445-5:2014 gibt im Anhang C Bedingungen für die Konstruktion von Zugangs- und Besichtigungsöffnungen,

von Verschlüssen und besonderen Verschlusselementen.

ANMERKUNG Dieser Teil gilt für Konstruktion und Berechnung von Behältern vor der Inbetriebnahme. Er kann auch, mit

entsprechenden Anpassungen, für Berechnungen oder analytische Nachweise im Betrieb verwendet werden.

## Récipients sous pression non soumis à la flamme - Partie 3 : Conception

Cette partie de la présente norme européenne spécifie les exigences relatives à la conception des récipients sous

pression non soumis à la flamme couverts par l’EN 13445-1:2014 et construits en aciers conformes à

l’EN 13445-2:2014.

L’Annexe C de l’EN 13445-5:2014 spécifie les exigences relatives à la conception des ouvertures d’accès et

d’inspection, des mécanismes de fermeture et des éléments de verrouillage spéciaux.

NOTE Cette partie s'applique à la conception des récipients avant mise en service. Elle peut être utilisée pour les calculs

ou l'analyse en service sous réserve d'apporter les ajustements appropriés.

## Neogrevane (nekurjene) tlačne posode - 3. del: Konstruiranje - Dopolnilo A3

### General Information

### Relations

### Standards Content (Sample)

SLOVENSKI STANDARD

01-maj-2018

1HRJUHYDQHQHNXUMHQHWODþQHSRVRGHGHO.RQVWUXLUDQMH'RSROQLOR$

Unfired pressure vessels - Part 3: Design

Unbefeuerte Druckbehälter - Teil 3: Konstruktion

Récipients sous pression non soumis à la flamme - Partie 3 : Conception

Ta slovenski standard je istoveten z: EN 13445-3:2014/A3:2017

ICS:

23.020.32 7ODþQHSRVRGH Pressure vessels

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 13445-3:2014/A3

EUROPEAN STANDARD

NORME EUROPÉENNE

August 2017

EUROPÄISCHE NORM

ICS 23.020.30

English Version

Unfired pressure vessels - Part 3: Design

Récipients sous pression non soumis à la flamme - Unbefeuerte Druckbehälter - Teil 3: Konstruktion

Partie 3 : Conception

This amendment A3 modifies the European Standard EN 13445-3:2014; it was approved by CEN on 2 July 2017.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of

this amendment into the relevant national standard without any alteration. Up-to-date lists and bibliographical references

concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN

member.

This amendment exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, 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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION

COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 13445-3:2014/A3:2017 E

worldwide for CEN national Members.

Contents Page

European foreword . 3

1 Modification to Clause 15 . 4

European foreword

This document (EN 13445-3:2014/A3:2017) has been prepared by Technical Committee CEN/TC 54

“Unfired pressure vessels”, 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 or by endorsement, at the latest by February 2018, and conflicting national standards shall be

withdrawn at the latest by February 2018.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. CEN 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

European Free 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

EN 13445-3:2014.

According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following

countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, 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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

1 Modification to Clause 15

Replace Clause 15 by the following:

15 Pressure vessels of rectangular section

15.1 Purpose

This clause specifies requirements for the design of unreinforced and reinforced pressure vessels of

rectangular cross-section. For fatigue, designs shall be checked against Clause 18. Thermal loads or effects

are not considered in this clause.

15.2 Specific definitions

The following terms and definitions apply in addition to those in Clause 3. The governing stresses in this

clause are not structural stress within the meaning of Clause 18.

15.2.1

membrane stress

equivalent uniform stress through the wall of the vessel, see also C.4.4.2

15.2.2

bending stress

equivalent linear distributed stress through the wall of the vessel, see also C.4.4.3

15.3 Specific symbols and abbreviations

The following symbols and abbreviations apply in addition to those in Clause 4:

a is the inside corner radius;

A is the area in vessel’s longitudinal direction without hole between stiffeners or between stiffener

walls;

A is the area A reduced by hole;

h

A is the required reinforcing area;

rf

A1 is the cross-sectional area of a reinforcing member which is attached to the short side of a vessel;

A is the cross-sectional area of a reinforcing member which is attached to the long side of the vessel;

A is cross sectional area of short side stiffener webs at corner;

w1

A is cross sectional area of long side stiffener webs at corner;

w2

A’ is the area of that part of the composite section above or below the calculation point;

A’ is the area of the reinforcement web;

web

b is the unsupported width of a flat plate between reinforcing elements, see Figure 15.6–1;

b is the weld throat dimension of the continuous weld;

cw

b is the effective width of a plate in combination with a reinforcing member, see Figure 15.6–1;

e

b is the pitch between centrelines of reinforcing members on a vessel;

R

bv is the length of side wall (either h or H);

b is the weld throat dimension of the intermittent weld;

w

C is a shape factor determined from the long and short sides of an unsupported plate between

stiffeners, see Table 15.6–2;

c is the distance from the neutral axis of a section to the outer fibre of a section and is positive when

inwards;

d is either the diameter of an opening or the inside diameter of a welded connection if attached by a

full penetration weld;

G is the shear modulus (by steel appr. E/2.6);

g is the length of an unsupported span;

g is the gap between intermittent welds;

w

h is the inside length of the long side;

h is the distance between the neutral axes of reinforcing members on the long side;

H is the inside length of the short side;

H is the distance between the neutral axes of reinforcing members on the short side;

I is the applicable second moment of area;

I , I I is the second moment of area per unit width of a plate strip;

1 2, 3

I is the second moment of area of the combined reinforcing member and plate on the short side of

the vessel;

I is the second moment of area of the combined reinforcing member and plate on the long side of the

vessel;

J , J is the stress correction factors of short vessels;

1 2

j is the distance from the neutral axis of the centroid of A’;

j is the distance from the neutral axis of the centroid of A` ;

web web

k is a factor, see Formula (15.5.2–4) or (15.6.5–5);

k is factor, see Formula (15.5.3–13);

k2 is factor, see Formula (15.5.3–14);

K is a factor for unreinforced vessel to Figure 15.5–1, see Formula (15.5.1.2–12);

Lv is the length of vessel;

L is the half length of the shorter side of vessel (see Figure 15.5–1);

L is the half length of the longer side of vessel;

L is the distance from centreline of shorter side plate to calculation point (mid of ligament or weld

x

seam) in perpendicular direction to vessel axis;

L is the distance from centreline of longer side plate to calculation point (mid of ligament or weld

y

seam) in perpendicular direction to vessel axis;

l is the length of the intermittent weld;

w

M is the bending moment at the middle of the long side in transversal direction of vessel, it is positive

A

when the outside surface of the vessel (or reinforcement) has compressive stress. It is expressed as

bending moment per unit length (in N·mm/mm);

M is the bending moment in the corner of the vessel;

BC

M is the bending moment at the middle of the short side of the vessel;

D

M is the bending moment at distance L ;

X x

M is the bending moment at distance L ;

y y

N is factor, see Formula (15.5.3–10);

p is the hole pitch along the plate length, see Figure 15.5–2;

p is the diagonal hole pitch in triangular hole pattern, see Figure 15.5–2;

s

Q is the shear force;

S is the first moment of area of short side reinforcement cross section at corner in respect to outside

surface of shell plate;

S is the first moment of area of long side reinforcement cross section at corner in respect to outside

surface of shell plate;

t is the thickness of web;

w

W is the elastic section modulus of combined cross section;

W is the plastic section modulus of combined (shell wall +stiffener) cross section:

p

α is H / h;

α is H / h ;

1 1 1

α is L / L ;

2 2 1

β is the angle between the line of the holes and the long axis, see Figure 15.5–2;

θ is an angle indicating position at the corner of a vessel, see Figure 15.5–2;

μ is ligament efficiency;

σ is bending stress;

b

σ is membrane stress;

m

ϕ is a factor, see Formula (15.5.1.2–15);

15.4 General

The formulas given in this subclause shall be used for calculation of the membrane and bending stresses in

unreinforced and reinforced rectangular pressure vessels. The total stress at the point of consideration shall

be taken as the sum of the membrane stress and the bending stress at that location.

For pressure vessels provided with doors a special analysis shall be performed to detect any deformation in

the door and the edge of the vessel.

Special care should be taken in the choice of gasket for the door.

15.5 Unreinforced vessels

15.5.1 Unreinforced vessels without a stay

15.5.1.1 General

This method applies to vessels of the type shown in Figure 15.5-1. The given formulas are applicable to

vessels with length Lv < 4h. The use of method for shorter vessels is conservative. The walls of short vessels

with length Lv < 2h may be designed acc. to requirements in cl. 15.5.5.

It is assumed that the thicknesses of the short and long sides are equal. When they are not, the method

in 15.5.3 shall be used.

15.5.1.2 Unperforated plates

Where the thickness of the smaller side is not the same as the thickness of the longer side, the calculation

method in 15.5.3 shall be used.

For unreinforced vessels conforming to Figure 15.5-1, the membrane stresses are determined from the

following formulas:

at C,

Pa+ L

( )

σ = (15.5.1.2-1)

( )

m

C

e

at D,

σ = σ

( ) ( )

m m

DC

at B,

Pa+ L

( )

σ = (15.5.1.2-2)

( )

m

B

e

at A,

σσ=

( ) ( )

mm

AB

at a corner, e.g. between B and C, it is given by:

P

σ = a++LL (15.5.1.2-3)

( )

( )

m 2 1

BC−

e

The second moment of area is given by:

I = I = e /12 (15.5.1.2-4)

1 2

Figure 15.5-1 — Unreinforced vessels

The bending stresses shall be determined from the following formulas:

at C,

e

2

σ =± 2M + P 2aL⋅− 2aL⋅+ L (15.5.1.2-5)

( )

( )

bA 2 12

C

4I

at D,

e

2 2

σ =± 2M + P 2aL⋅− 2aL⋅+ L − L (15.5.1.2-6)

( )

( )

bA 2 12 1

D

4I

at A,

Me

A

σ =± (15.5.1.2-7)

( )

b

A

2I

at B,

e

σ =±+2M PL (15.5.1.2-8)

( )

( )

bA 2

B

4I

at the corner,

e

σ =± 22M + P aL cosθθ−−L (1 sin )+ L (15.5.1.2-9)

( ) ( )

{ }

bA 2 1 2

BC−

4I

For these formulas the following shall apply:

a) the maximum value of σ is given where θ= arctan LL/ (15.5.1.2-10)

( ) ( )

b 1 2

B−C

and

b) the bending moment M per unit length, is given by:

A

M PK⋅−() (15.5.1.2-11)

A 3

where

22 2 2 3 2 2

L 6ϕ ⋅α − 3πϕ + 6ϕ +α + 3α − 6ϕ−+2 15. πα ⋅ϕ+ 6ϕ⋅α

( )

1 2 22 2 2

(15.5.1.2-12)

K =

3 2α +πϕ+ 2

( )

L

α = (15.5.1.2-13)

L

a

ϕ= (15.5.1.2-14)

L

At a location, the maximum stress shall be obtained as stated in 15.4 by summarizing the membrane and

bending stresses.

=

15.5.1.3 Perforated plates

The vessel with perforated side plates shall fulfil the requirements of unperforated plates in 15.5.1.2. Side

plate of vessel (or pipe) may be perforated by row or rows of holes. The pattern of holes placing is triangular

or square. The ligament efficiency of a perforated side plate is given by:

pd−

p− d 1

s

µ= min ; (15.5.1.3-1)

ppcosβ

s

where β is the angle of hole pattern as defined in Figure 15.5-2.

Ligament efficiency μ is used to reduce the allowable stresses in 15.5.5 of membrane and bending stresses in

perpendicular direction to vessel axis. For short vessels acc. 15.5.4 the ligament efficiency shall be minimum

of those defined both in direction of longitudinal axis and perpendicular to longitudinal axis of the vessel and

only the first part of Formula (15.5.1.3-1) shall be used.

If the pitch and diameter varies in plate, the smallest value of μ shall be chosen. The strength at single

opening, even for opening in row of holes, shall be checked acc. to chapter 15.7.

Figure 15.5-2 — Unreinforced vessels with perforated sides

If the ligament efficiency μ is at least 0,2, the membrane stresses shall be determined at point of

consideration (mid of ligament) in direction perpendicular to vessel axis from the following formulas:

On longer side

(15.5.1.3-2)

σσ=

( ) ( )

mm

yB

**...**

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