EN 13445-3:2002/A6:2006

SLOVENSKI STANDARD
01-maj-2006
1HRJUHYDQHWODþQHSRVRGH±GHO.RQVWUXLUDQMH
Unfired pressure vessels - Part 3: Design
Unbefeuerte Druckbehälter - Teil 3: Konstruktion
Récipients sous pression non soumis a la flamme - Partie 3: Conception
Ta slovenski standard je istoveten z: EN 13445-3:2002/A6:2006
ICS:
23.020.30
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 13445-3:2002/A6
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2006
ICS 23.020.30
English Version
Unfired pressure vessels - Part 3: Design
Récipients sous pression non soumis à la flamme - Partie Unbefeuerte Druckbehälter - Teil 3: Konstruktion
3: Conception
This amendment A6 modifies the European Standard EN 13445-3:2002; it was approved by CEN on 24 June 2005.
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 Central Secretariat 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 Central Secretariat has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 13445-3:2002/A6:2006: E
worldwide for CEN national Members.

Foreword
This document (EN 13445-3:2002/A6:2006) has been prepared by Technical Committee CEN/TC 54 “Unfired
pressure vessels”, the secretariat of which is held by BSI.
The document includes the text of the amendment itself. The corrected pages of EN 13445-3 will be delivered
as Issue 18 of the standard
This amendment is based on EN 13445-3 up to issue 16 (2005-09).
This Amendment to the European Standard EN 13445-3:2002 shall be given the status of a national standard,
either by publication of an identical text or by endorsement, at the latest by August 2006, and conflicting
national standards shall be withdrawn at the latest by August 2006.
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).
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden,
Switzerland and United Kingdom.
Replace the whole of Clause 10 with the following text:
10 Flat ends
10.1  Purpose
10.1.1 This clause specifies methods for determining the thickness of circular and non-circular unstayed flat
ends under pressure and for providing adequate reinforcement for openings fitted in such ends. Loads other
than pressure are not considered.
NOTE 1 For welded flat ends, the method takes into account the stresses caused by the junction forces and moments.
For bolted flat ends, the method takes into account the stresses caused by the forces and moments due to the flange and
bolting.
NOTE 2 For the design of vessels of rectangular cross-section, refer to Clause 15.
10.1.2 Stayed plates, i.e. plates supported by braces, stay bars or stay tubes, are not considered in this
clause.
NOTE Stayed plates may be calculated using the formulae and methods of the European Standard for Shell Boilers
(see EN 12953) with the nominal design stresses of this standard.
These rules do not apply to heat exchanger tubesheets, which are covered by Clause 13.
10.1.3 These rules do not apply to self-sealing covers, i.e. to covers where compression of the gasket is
obtained through the action of internal pressure and which are equipped with a bolting-up device.
10.2  Specific definitions
The following specific definitions apply in addition to those in Clauses 3 and 11.
10.2.1
flat end
unstayed flat plate of generally constant thickness, connected to a shell by either welding or bolting, not
supported by stays or stay-tubes, not strengthened by beams, and supported only at its periphery so that it is
subject predominantly to bending
10.2.2
hub
cylindrical or conical projection on a flat end provided so that the end may be butt welded to a cylindrical shell
(see Figure 10.4-1)
10.2.3
relief groove
peripheral groove in a flat end to be butt welded to a cylindrical shell (see Figure 10.4-3)
10.2.4
annular plate
flat end of annular form, connected to one cylindrical shell at its outside diameter and another at its inside
diameter, and subject predominantly to bending and not shear
10.3  Specific symbols and abbreviations
The following symbols apply in addition to those in Clauses 4 and 11.
A is the nozzle reinforcement area, see 10.6.2.2;
a’ is the smaller width dimension in a rectangular, elliptical or obround end;
b’ is the greater width dimension in a rectangular, elliptical or obround end;
C , C are the shape factors for calculation of circular flat ends;
1 2
C , C are the shape factors for calculation of flat ends of non-circular shape;
3 4
c is the mean distance between the gasket reaction and the bolt pitch circle diameter;
D is the equivalent diameter of an end with a hub, see Figure 10.4-1;
eq
D is the diameter of the flat part of an end with a tapered hub, see Figure 10.4-1;
F
D is the inside diameter of the cylindrical shell welded to a flat end. When the thickness of the cylindrical
i
shell adjacent to the shell is not constant, see Figure 10.4-1b), D is the inside diameter to the equivalent
i
cylinder of mean thickness e ;
s
D is the inside diameter of an annular plate;
X
D is the outside diameter of an annular plate;
Y
d is the diameter of an opening, the equivalent diameter of a nozzle, the mean diameter of two openings or
the mean equivalent diameter of two nozzles;
d is the nozzle inside diameter;
i
d is the nozzle outside diameter;
e
e is the required thickness for the flange extension on a flat end;
e is the analysis thickness of the external section of a nozzle, see Figure 10.6-3;
ab
e’ is the analysis thickness of the internal protrusion of a nozzle, see Figure 10.6-4;
ab
e is the analysis thickness of an end with a hub;
af
e is the required thickness of the nozzle cylinder for pressure loading;
b
e is the required thickness of an unpierced end, in the design of a pierced end;
o
e is the required thickness under a relief groove, see Figure 10.4-3;
r
e is the analysis thickness of a uniform cylindrical shell, or the equivalent thickness of a tapered cylindrical
s
shell, adjacent to a flat end;
f is the material nominal design stress at ambient temperature;
A
f is the nominal design stress at calculation temperature of the nozzle;
b
f is the lower of the nominal design stresses f of the end and f of the shell;
min s
f is the nominal design stress at calculation temperature of the shell;
s
h is the smallest distance between the centre of an opening and the inside of the shell, see Figure 10.6-1;
h is the distance between the external wall of an end with a relief groove and the weld on the shell (see
w
Figure 10.4-3);
j is determined from the position of an opening, see 10.6.2.1;
k is the distance between the centres of two openings, see Figure 10.6-2;
l is the external length of a nozzle effective for reinforcement;
l’ is the internal length on a protruding nozzle effective for reinforcement, see Figure 10.6-3;
l is the length of cylindrical shell, as shown in Figures 10.4-1 to 10.4-3, which contributes to the strength of
cyl
the flat end (all types of flat ends) and of the end-to-shell junction (ends welded directly to the shell);
n is the number of bolts in a flat end of non circular shape
r is the inside radius of a hub, see Figure 10.4-1;
r is the inside radius of the relief groove, see Figure 10.4 -3;
d
t is the mean bolt pitch in a bolted flat end;
B
Y is the calculation coefficient for opening reinforcement, see equation 10.6-3;
Y is the calculation coefficient for opening reinforcement, see equation 10.6-4;
ν is the Poisson’s ratio of the material for the end.
10.4  Unpierced circular flat ends welded to cylindrical shells
10.4.1  General
The requirements of 10.4.2 to 10.4.5 apply to the following types of unpierced, circular flat end:
— with a hub, see Figure 10.4-1;
—  welded directly to the shell, see Figure 10.4-2;
— with a relief groove, see Figure 10.4-3.
10.4.2  Limitations
10.4.2.1 The length l (see Figures 10.4-1 to 10.4.-3) shall not contain another junction between the shell and
cyl
an end, tubesheet, flange or other shell.
10.4.2.2 For an end with a hub, the following conditions shall apply:
a) the inside radius of the hub shall meet the following: r ≥ e and r ≥ 1,3 e ;
s af
b) the hub and adjacent cylinder may be offset, but their wall centre-lines shall not be offset by an amount
which is greater than the difference between their nominal thicknesses;
c) a taper hub shall have a slope not exceeding 1:3;
d) where the thickness of the cylindrical shell adjacent to the flat end is uniform (see Figure 10.4-1(a)), l
cyl
shall be calculated as follows:
l = 0,5 (D + e )e (10.4-1)
cyl i s s
e) where the thickness of the cylindrical shell adjacent to the flat end is tapered (see Figure 10.4-1(b)), a
value of l shall be assumed and the mean thickness over that length calculated. This thickness shall be
cyl
inserted into equation (10.4.1) and the required value of l calculated. If l required is greater than the
cyl cyl
assumed value, the calculation shall be repeated using a larger assumed value.
Flat ends which do not meet these conditions shall be treated as ends welded directly to the shell.
10.4.2.3 For a flat end welded directly to the shell (see Figure 10.4-2), l is given by:
cyl
lD=+()ee (10.4-2)
cyl i s s
10.4.2.4 For a flat end with a relief groove (see Figure 10.4-3), the following conditions shall apply:
a) l is also given by equation (10.4-2);
cyl
b) radius r shall be at least equal to 0,25e or 5 mm, whichever is greater;
d s
c) the centre of the radius shall lie within the thickness of the flat end and not outside it, and the distance h
w
of the end-to-shell weld to the outside surface of the end shall be greater than (e - 2mm), see Figure 10.4-3.

10.4.3  Flat ends with a hub
The minimum required thickness for a flat end with a hub is given by:
P
e = C ⋅ D (10.4-3)
1 eq
f
When the distance from the inside surface of the flat portion of the end to the end-to-shell weld is larger than
l + r, the coefficient C is given by Figure 10.4-4 or by :
cyl 1
 D + e   e 
i s s
C = MAX 0,40825 A , 0,299 1+ 1,7  (10.4-4)
1  1 
  
D D
   
i i
where :
 e 
s
A = B 1− B (10.4-5)
1 1 1
 
2()D + e
 
i s
2 4
3f e  3 D  P 3()2D + e e
s i i s s
B = 1−   +   − (10.4-6)
1    
P D + e 16 D + e f 4
    ()D + e
i s i s
i s
When this distance is lower than l + r , then the coefficient C is still given by Figure 10.4-4 but using P/f
cyl 1
instead of P/f .
min
For a uniform thickness shell per Figure 10.4-1 a),
D = D − r (10.4-7)
eq i
For a tapered shell per Figure 10.4-1 b),
()D + D
i F
D = (10.4-8)
eq
The following condition shall be met:
e ≥ e (10.4-9)
af
10.4.4 Flat ends welded directly to the shell
10.4.4.1 The minimum required thickness for the end is given, for a normal operating case, by the greatest of
the following:
 
 
 P P
 
e= max C ⋅ D  , C ⋅ D  (10.4-10)
 1 i 2 i 
   
f f
 
  min
  
where
ff= min ;f (10.4-11)
{}
min s
C is given:
− either by Figure 10.4-4
− or by equation (10.4-4) calculated with the A value derived from equations (10.4-5) and
(10.4-6) using f instead of f.
min
C is given by Figure 10.4-5.
P
Instead of reading C on Figure 10.4-5, the term C ⋅D may also be calculated directly by means of the
2 i
f
min
method given in 10.4.6
NOTE This method is based on the resolution of a cubic equation
When C is less than 0,30, only the first term of equation (10.4-10) shall be considered.
10.4.4.2 For an exceptional operating case and for a hydrostatic testing case the calculation of e shall take
into account only the first term of equation (10.4-10):
P
e = C ⋅ D (10.4-12)
1 i
f
10.4.4.3 In equations (10.4-10) to (10.4-12), f, f and P shall be understood as generic symbols valid for all
s
types of load cases (normal, exceptional, testing) and having the following meaning:
— for a normal operating case, f is f , f is (f ) and P is P ;
d d
s d s
— or an exceptional operating case, f is f , f is (f ) and P is P ;
exp exp s exp
s
— for an hydrostatic testing case, f is f , f is (f ) and P is P .
test test s test
s
10.4.4.4 For a normal operating case, the minimum required thickness of the end may alternatively be
calculated using equation (10.4-12) instead of (10.4-10), provided a simplified assessment of the fatigue life of
the flat end to shell junction is performed according to Clause 17. In performing this assessment:
— the following stress index value shall be used :
P
 
max,1
η = 3  (10.4-13)
 
P
 ma
...