BS EN 1 4025:201 3+A1 :201 6

BSI Standards Publication

Tanks for the transport of
dangerous goods — Metallic
pressure tanks — Design and
construction


BRITISH
STANDARD
BRITISH
BRITISH STANDARD
STANDARD

BS EN 1 4025:201 3+A1 :201 6
BS
BS EN
EN 11 4025:201
4025:201 33
National foreword
National foreword
National
This
Britishforeword
Standard

is the UK implementation of

EN 1 4025:201 3+A1 :201 6. It supersedes BS EN 1 4025:201 3 which

is withdrawn.
The start and finish of text introduced or altered by amendment is
indicated in the text by tags. Tags indicating changes to CEN text carry
the number of the CEN amendment. For example, text altered by CEN
amendment A1 is indicated by
.

!"

This standard is primarily intended as a code for the design and
construction of tanks for the transport of dangerous goods, subject
to the provisions of Chapters 4.3 and 6.8 of the RID/ADR/ADN. For
instance, EN 1 4025 is a referenced standard in ADR paragraph
6.8.2.6.1 , and its provisions should be regarded as normative for
these tanks, except where ADR permits the use of other standards
specific to dangerous goods to be transported, e.g. cryogenic gases
and LPG.
and
LPG.
and
LPG.
BS
EN
11 4025
isis one
of
standards
that
might
be

for
the
design
construction
UN Portable
the
BS
EN
4025and
one
of several
severalof
standards
thatTanks
mightsubject
be used
usedto
for
the
design
and
construction
of
UN
Portable
Tanks
subject
to
the
provisions

of
Chapters
4.2
and
6.7
of
the
RID/ADR/ADN
and
also
the design of
andChapters
construction
of 6.7
UN of
Portable
Tanks subject
toalso
the
provisions
4.2
and
the
RID/ADR/ADN
and
of the IMDG
Code.
It should
be6.7
noted

thatRID/ADR/ADN
regulations inand
Chapters
provisions
of
Chapters
4.2
and
of
the
also
of the
the
IMDG
ItIt should
should the
be noted
noted
that
regulations
in
Chapters
4.2
andIMDG
6.7 doCode.
not prescribe
use ofthat
this regulations
standard. Alternative
of

Code.
be
in Chapters
4.2
and
6.7
do
not
prescribe
the
use
of
this
standard.
Alternative
standards
by the
for Transport
for
4.2
and 6.7are
dopermitted
not prescribe
theUK
useDepartment
of this standard.
Alternative
standards
are
permitted

by
the
UK
Department
for
Transport
for
these
tanks.
standards
are permitted by the UK Department for Transport for
these
tanks.
The UKtanks.
committee advises users that there might be conflicting
these
provisions
in this standard
provisions
in Chapters
The UK committee
advises with
usersreference
that theretomight
be conflicting
4.2
and
6.7
of
RID/ADR/ADN

and
the
IMDG
Code.
Users
should
provisions in this standard with reference to provisions in
Chapters
be
aware
that
UN
Portable
Tanks
designed
and
constructed
in
4.2 and 6.7 of RID/ADR/ADN and the IMDG Code. Users should
accordance
with
this
standard
may
not
be
accepted
in
all
parts

be aware that UN Portable Tanks designed and constructed in of
the
world. with this standard may not be accepted in all parts of
accordance
the world.
The
UK participation in its preparation was entrusted to Technical
Committee
AUE/1 8, Tanks
the transport
of dangerous
goods.
The UK participation
in its for
preparation
was entrusted
to Technical
Committee
AUE/1 8, Tanks
for the transport
of dangerous
A
list of organizations
represented
on this committee
can goods.
be
obtained
on request torepresented
its secretary.on this committee can be

A list of organizations
obtained
on request
secretary.
This
publication
doestonotitspurport
to include all the necessary
provisions
of a contract.
are to
responsible
correct
This publication
does notUsers
purport
include allfortheitsnecessary
application.
provisions of a contract. Users are responsible for its correct
application.
©
The British Standards Institution 201 3. Published by BSI Standards
Limited
201 3 Standards Institution 201 6.
© The British
Published
Standards
Limited 201 6
ISBN
978 0by

580BSI76782
1
ISBN1 3.300;
978 0 580
88461 0
ICS
23.020.20
ICS 1 3.300; 23.020.20
Compliance
with a British Standar
legal obligations.
Compliance
with a British Standard cannot confer immunity from
legal obligations.

This British Standard was published under the authority of the
Standards Policy
and since
Strategy
Committee on 30 November 201 3.
Amendments
issued
publication

Amendments/corrigenda
issued since publication
Date
Text affected
Date


Text affected

31 July 201 6

Implementation of CEN amendment A1 :201 6


EUROPEAN STANDARD

EN 14025:2013+A1

NORME EUROPÉENNE
EUROPÄISCHE NORM

June 2016

ICS 13.300; 23.020.20

Supersedes EN 14025:2013

English Version

Tanks for the transport of dangerous goods - Metallic
pressure tanks - Design and construction
Citernes destinées au transport de matières
dangereuses - Citernes métalliques sous pression Conception et fabrication

Tanks für die Beförderung gefährlicher Güter Metallische Drucktanks - Auslegung und Bau

This European Standard was approved by CEN on 31 August 2013 and includes Amendment 1 approved by CEN on 29 April

2016.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a 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 European Standard 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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
C O M I TÉ E URO P É E N D E N O RM ALI S ATI O N
E U RO P ÄI S C H E S KO M I T E E F Ü R N O RM U N G

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2016 CEN

All rights of exploitation in any form and by any means reserved
worldwide for CEN national Members.

Ref. No. EN 14025:2013+A1:2016 E


BS
1 4025:201 3+A1 :201 6
BS EN
EN 14025:2013+A1:2016

EN
14025:2013+A1:2016
(E)
E N 14025:2013+A1:201 6 (E)

Contents

Page

European foreword ....................................................................................................................................................... 4
1

Scope .................................................................................................................................................................... 5

2

Normati ve references .................................................................................................................................... 5

3
3.1
3.2

Terms , definitions and symbols ................................................................................................................. 7
Terms and definitions ................................................................................................................................... 7
Symbols ............................................................................................................................................................... 7

4
4.1
4.2


Materials ............................................................................................................................................................. 8
General ................................................................................................................................................................ 8
Compatibility .................................................................................................................................................... 9

5
5.1
5.2
5.3
5.4
5.5
5.6

Design .................................................................................................................................................................. 9
General ................................................................................................................................................................ 9
Minimum shell thickness ............................................................................................................................. 9
Reduction of shell thickness........................................................................................................................ 9
Protection of the shell ................................................................................................................................ 10
Protection of equipment............................................................................................................................ 10
Other design requirements ...................................................................................................................... 11

6
6.1
6.1.1
6.1.2

Calculation ...................................................................................................................................................... 11
General ............................................................................................................................................................. 11
General ............................................................................................................................................................. 11
Calculation scheme for the wall thickness of metallic pressure tanks of RID/ADR
Chapte r 6.8...................................................................................................................................................... 11

6.1.3 Calculation scheme for the wall thickness of metallic portable pressure tanks of
RID/AD R chapter 6.7 .................................................................................................................................. 12
6.2
Design criteria ............................................................................................................................................... 13
6.3
Calculation for internal pressure ........................................................................................................... 15
6.3.1 General ............................................................................................................................................................. 15
6.3.2 Wall thickness of the cylindrical section ............................................................................................. 15
6.3.3 Wall thickness of ends ................................................................................................................................ 15
6.3.4 Wall thickness of conical sections .......................................................................................................... 19
6.3.5 Openings and reinforcements ................................................................................................................. 21
6.3.6 Manhole covers ............................................................................................................................................. 28
6.3.7 Flanges , joints , bolts .................................................................................................................................... 33
6.4
Calculation for external pressure........................................................................................................... 34
6.4.1 General ............................................................................................................................................................. 34
6.4.2 Tanks, where external over pressure is part of operatin g conditions ..................................... 35
6.4.3 Tanks, where external over pressure is not part of operating conditions .............................. 35
6.4.4 Test .................................................................................................................................................................... 35
6.5
Tan k to frame connection/interface ..................................................................................................... 35
7
7.1
7.2
7.3
7.3.1

2

Construction an d manufacturing ........................................................................................................... 36

General requirements ................................................................................................................................ 36
Cutting .............................................................................................................................................................. 36
Forming............................................................................................................................................................ 37
General ............................................................................................................................................................. 37


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7.3.2
7.3.3
7.3.4
7.3.5
7.4
7.4.1
7.4.2
7.4.3
7.4.4
7.5
7.5.1
7.5.2
7.5.3
7.5.4
7.5.5


Cold forming ................................................................................................................................................... 37
Hot forming ..................................................................................................................................................... 37
Ends ................................................................................................................................................................... 37
Heat treatment an d normalising............................................................................................................. 37
Welding ............................................................................................................................................................ 38
Qualification ................................................................................................................................................... 38
Welded joints ................................................................................................................................................. 38
Examination an d testing of welds ........................................................................................................... 38
Temporary attachments ............................................................................................................................ 40
Manufacturin g tolerances ......................................................................................................................... 40
Plate alignment ............................................................................................................................................. 40
Defects o f form ............................................................................................................................................... 41
Thickness ......................................................................................................................................................... 41
Dishe d ends ..................................................................................................................................................... 41
Cylindrical sections ...................................................................................................................................... 41

8
8.1
8.2
8.3

Repairs .............................................................................................................................................................. 42
General ............................................................................................................................................................. 42
Repair of surface defects in the parent metal .................................................................................... 42
Repair of weld defects ................................................................................................................................. 42

Annex A (informative) Sample calculation for tank containers according to RID/ADR
Chapter 6.8" .................................................................................................................................................... 43
A.1


Introduction ................................................................................................................................................... 43

A.2

Dimensions, characteristics of materials, operating and testing conditions .......................... 43

A.3

Calculation according to branch A .......................................................................................................... 44

A.4

Calculation according to branch B .......................................................................................................... 44

A.5

Calculation according to branch C .......................................................................................................... 45

A.6

Calculation according to branch D ......................................................................................................... 47

A.7

Results .............................................................................................................................................................. 54

Annex B (informative) Explosion pressure shock resistant design of tanks .......................................... 56
Bibliography ................................................................................................................................................................. 58


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European foreword
This document (EN 14025:2013+A1:2016) has been prepared by Technical Committee CEN/TC 296
“Tanks for the transport of dangerous goods”, the secretariat of which is held by AFNOR.
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 December 2016, and conflicting national standards
shall be withdrawn at the latest by December 2016.
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 includes Amendment 1 approved by CEN on 29 April 2016.
This document supersedes

! EN 14025:2013 " .

The start and finish of text introduced or altered by amendment is indicated in the text by tags

! deleted text"


! ".

This document is submitted for reference into the RID [9] and/or in the technical annexes of the ADR
[10] .
NOTE
The
technical
annexes
are
available
at
the
following
website:
./trans/danger/danger.htm for ADR and for RID at respectively.

This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
According to the CEN-CENELEC Internal Regulations, the national standards organizations 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, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

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1 Scope
This European Standard specifies the minimum requirements for the design and construction of
metallic pressure tanks having a maximum working or test pressure exceeding 50 kPa (0,5 bar), for the
transport of dangerous goods by road and rail and sea. This European Standard includes requirements
for openings, closures and structural equipment; it does not cover requirements of service equipment.
For tanks for the transport of cryogenic liquids, EN 13530-1 and EN 13530-2 apply.
NOTE 1
Design and construction of pressure tanks according to the scope of this European Standard are
primarily subject to the requirements of RID/ADR, 6.8.2.1, 6.8.3.1 and 6.8.5, as relevant. In addition, the relevant
requirements of RID/ADR, columns 12 and 13 of Table A to chapter 3.2, 4.3 and 6.8.2.4 apply. For the structural
equipment subsections 6.8.2.2 and 6.8.3.2 apply, as relevant. The definitions of RID/ADR 1.2.1 are referred to. For
portable tanks see also Chapter 4.2 and Sections 6.7.2 and 6.7.3 of RID and ADR. In addition, the relevant
requirements of RID/ADR, columns 10 and 11 of Table A to Chapter 3.2, 4.2, 6.7.2 and 6.7.3 apply. The paragraph
numbers above relate to the 2013 issue of RID/ADR which are subject to regular revisions. This can lead to
temporary non-compliances with EN 14025. It is important to know that requirements of RID/ADR take
precedence over any clause of this standard.
NOTE 2
This standard is applicable to liquefied gases including LPG, however for a dedicated LPG standard see
EN 12493.

If not otherwise specified, provisions which take up the whole width of the page apply to all kind of
tanks. Provisions contained in a single column apply only to:
road and rail pressure tanks according to portable tanks according to RID/ADR chapter 6.7

RID/ADR chapter 6.8 (left-hand column);
(right-hand column).

2 Normati ve references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 287-1, Qualification test of welders — Fusion welding — Part 1 : Steels
EN 1418, Welding personnel — Approval testing of welding operators for fusion welding and resistance
weld setters for fully mechanized and automatic welding of metallic materials
EN 1435, Non-destructive examination of welds — Radiographic examination of welded joints
EN 1591-1, Flanges and their joints — Design rules for gasketed circular flange connections — Part 1:
Calculation method
EN 10204, Metallic products - Types of inspection documents
EN 13094:2008, Tanks for the transport of dangerous goods — Metallic tanks with a working pressure
not exceeding 0,5 bar — Design and construction
EN 13445-2, Unfired pressure vessels - Part 2: Materials
EN 13445-3:2009, Unfired pressure vessels — Part 3: Design
EN 13445-4, Unfired pressure vessels - Part 4: Fabrication

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EN 13445-8, Unfired pressure vessels - Part 8: Additional requirements for pressure vessels of aluminium
and aluminium alloys
EN ISO 3834-1, Quality requirements for fusion welding of metallic materials — Part 1 : Criteria for the
selection of the appropriate level of quality requirements (ISO 3834-1 )
EN ISO 3834-2, Quality requirements for fusion welding of metallic materials — Part 2: Comprehensive
quality requirements (ISO 3834-2)
EN ISO 4136, Destructive tests on welds in metallic materials — Transverse tensile test (ISO 41 36)
EN ISO 5173, Destructive tests on welds in metallic materials — Bend tests (ISO 5173)
EN ISO 5817, Welding — Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding
excluded) — Quality levels for imperfections (ISO 5817)
EN ISO 9606-2, Qualification test of welders — Fusion welding — Part 2: Aluminium and aluminium alloys
(ISO 9606-2)
EN ISO 9712, Non destructive testing — Qualification and certification of NDT personnel (ISO 9712)
EN ISO 10042, Welding — Arc-welded joints in aluminium and its alloys — Quality levels for imperfections
(ISO 1 0042)
EN ISO 15607, Specification and qualification of welding procedures for metallic materials — General
rules (ISO 1 5607)
EN ISO 15609-1, Specification and qualification of welding procedures for metallic materials — Welding
procedure specification — Part 1 : Arc welding (ISO 1 5609-1 )
EN ISO 15609-3, Specification and qualification of welding procedures for metallic materials — Welding
procedures specification — Part 3: Electron beam welding (ISO 1 5609-3)
EN ISO 15609-4, Specification and qualification of welding procedures for metallic materials — Welding
procedure specification — Part 4: Laser beam welding (ISO 1 5609-4)
EN ISO 15613, Specification and qualification of welding procedures for metallic materials —
Qualification based on pre-production welding test (ISO 1 5613)
EN ISO 15614-1, Specification and qualification of welding procedures for metallic materials — Welding
procedure test — Part 1: Arc and gas welding of steels and arc welding of nickel and nickel alloys
(ISO 1 561 4-1 )

EN ISO 15614-2, Specification and qualification of welding procedures for metallic materials — Welding
procedure test — Part 2: Arc welding of aluminium and its alloys (ISO 1561 4-2)
EN ISO 17635, Non-destructive testing of welds — General rules for metallic materials (ISO 1 7635)
EN ISO 17637, Non-destructive testing of welds — Visual testing of fusion-welded joints (ISO 1 7637)
EN ISO 17640, Non-destructive testing of welds — Ultrasonic testing — Techniques, testing levels, and
assessment (ISO 1 7640)

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ISO 1496-3, Series 1 freight containers — Specification and testing — Part 3: Tank containers for liquids,
gases and pressurized dry bulk
ISO 7005-1, Pipe flanges — Part 1 : Steel flanges for industrial and general service piping systems

3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the following term and definition applies.

3.1.1
pressure-tank
tank as defined in the international regulations for the transport of dangerous goods by road or rail

having a maximum working pressure or a test pressure exceeding 50 kPa (0,5 bar)

3.2 Symbols
The following general symbols are used throughout the text. They are listed in alphabetical order and
special symbols are explained with the relevant formulae. Additional symbols used in the text are
explained in:
RID/ADR Chapter 6.8
RID/ADR Chapter 6.7
A 1 minimum elongation at fracture of the metal chosen under tensile stress in %

di

inside diameter of an opening

D

internal diameter of shell in mm

DC mean diameter of the cylindrical part of the tank at the junction of a cone
De outside diameter of the cylindrical part of the tank or the straight flange of the dished end
Di
e

inside diameter of the cylindrical part of Di diameter of the shell (in m), but not less than
the tank or the straight flange of dished
1,80 m
end
minimum required wall thickness (in mm) of the shell

e0 minimum shell thickness for mild steel in mm, according to 6.8.2.1.18 and 6.8.2.19 of RID/ADR

e1 minimum shell thickness for the metal chosen in mm
ek wall thickness of a conical part of a shell
eR wall thickness of a hemispherical end
E

Young's modulus

fd

nominal design stress (allowable stress)

h

inside height of an ellipsoidal dished end

K

shape factor of ellipsoidal ends

MWP

maximum working pressure, in MPa

p design pressure, in MPa
p dyn equivalent dynamic pressure

MAWP maximum allowable working pressure, in
MPa
P


design pressure, in MPa

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p test
p vap

test pressure, in MPa
vapour pressure at 50 °C or at the design Pvap1 vapour pressure of the substance at 65 °C
temperature, whichever is the higher; to be
(according to 6.7.2.1 of RID/ADR)
taken as the numerical value of the
Pvap2 vapour pressure of the non-refrigerated
absolute pressure
liquefied gas depends on the portable
tank type (according to 6.7.3.1 of
RID/ADR)

Pc calculation pressure in MPa as specified
6.8.2.1.14 of RID/ADR

PT test pressure in MPA

in

r

inner knuckle radius, in mm

R

inside spherical radius of the central part of a torispherical end

Re guaranteed (upper) minimum yield strength or guaranteed minimum 0,2 % proof strength, in
N/mm² (for austenitic steel the 1 % proof strength may be chosen)

Re,t guaranteed (upper) minimum yield strength or guaranteed minimum 0,2 % proof strength, at the

relevant design temperature, in N/mm² (for austenitic steel the 1 % proof strength at the relevant
design temperature may be chosen)

Rm guaranteed minimum tensile strength, in N/mm²
Rm1 minimum tensile strength of the metal chosen in N/mm 2
Rm,t guaranteed minimum tensile strength at the relevant design temperature, in N/mm²
σ permissible stress in N/mm 2 , as defined in 6.8.2.1.16 of RID/ADR
S

safety factor

λ


welding coefficient

4 Materials
4.1 General
The tank shell shall be fabricated from metallic materials which shall be resistant to brittle fracture and
of adequate impact strength within the design temperature range. The material shall be suitable for
forming.
EN 13445-2 and -8 apply and the minimum material requirements given in RID/ADR Chapter 6.8 and
Chapter 6.7 shall be fulfilled.
RID/ADR Chapter 6.8

RID/ADR Chapter 6.7
Aluminium may only be used for the shells of
portable tanks when indicated in a portable tank
special provision assigned to a specific substance
in Column (11) of Table A of Chapter 3.2 RID/ADR
or when approved by the competent authority.

NOTE 1

For aluminium and aluminium alloys, see also EN 14286.

NOTE 2
RID/ADR restrict the use of materials with respect to the maximum yield and tensile strength of finegrained steel for welded shells, maximum ratios of yield/tensile strength for welded steel shells and of the
minimum elongation at fracture for welded fine- grained other steel and aluminium shells.

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Welded shells shall be fabricated from a material which has been shown to have acceptable welding
characteristics.

4.2 Compatibility
Shells, fittings, and pipework shall be constructed from materials which are:
a)

substantially immune to attack by the substance(s) intended to be transported; or

b)

properly passivated or neutralised by chemical reaction; or

c)

lined with corrosion-resistant material directly bonded to the shell or attached by equivalent
means.

They shall comply with
RID/ADR 6.8.2

RID/ADR 6.7.2.2 and 6.7.3.2


Gaskets shall be made of materials not subject to attack by the substances intended to be transported.
The materials of the tank, including any devices, gaskets, linings and accessories, shall not adversely
affect the substances intended to be transported in the tank.
Guidelines on material specifications in relation to the substances to be transported may be taken from
Annex B of EN 12285-1:2003.

5 Design
5.1 General
Tanks shall be designed to withstand without loss of contents the:
1)

operating conditions including static and dynamic forces in normal conditions of carriage. In
addition, the design of portable tanks shall account for the effects of fatigue, caused by repeated
application of these loads through the expected life of the portable tank;

2)

test conditions;

3)

!

explosion-pressure-shock resistant condition (if required) (see Annex B)

"

;


under consideration of Clause 6.
If sudden temperature differences are to be expected during filling or discharge of the tank the buckling
effect of one sided expansion or contraction should be taken into account.

5.2 Minimum shell thickness
The shell thickness shall not be less than that given in:
RID/ADR 6.8.2.1.17 to 6.8.2.1.18, see Figure 1 of RID/ADR 6.7.2.4 or 6.7.3.4, see Figure 2 of this
this standard
standard

5.3 Reduction of shell thickness
The reduction of the minimum shell thickness
(see Figure 1) is allowed if protection of the shell
against damage through lateral impact or
overturning is provided (see 5.4 and RID/ADR

When additional protection against shell damage
is provided as described in 5.4, portable tanks
with test pressure less than 2,65 bar may have the
minimum shell thickness reduced, in proportion to

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6.8.2.1.19 to 6.8.2.1.20 and 6.8.2.1.21 respectively)
but the minimum requirements given in RID/ADR
6.8.2.1.17 shall be met.

the protection provided (see RID/ADR 6.7.2.4.3 to
6.7.2.4.5).

For shells of rail tank wagons no reduction of the
minimum wall thickness due to protection is
allowed.

5.4 Protection of the shell
5.4.1

When required by 5.3 shells of:

tank containers

portable tanks

are protected against damage if one of the following measures is provided:
— structure, in which the shell is supported by a complete skeleton including longitudinal and
transverse structural members. This structure shall conform to the requirements of ISO 1496-3;
— double wall construction, where the aggregate thickness of the outer metal wall and the shell itself
is not less than the minimum shell thickness prescribed in:
— RID/ADR 6.8.2.1.18 and the thickness of the
inner shell wall is not less than the minimum

shell thickness prescribed in 6.8.2.1.19;

— RID/ADR 6.7.2.4.1 and 6.7.2.4.2 and the
thickness of the inner shell wall is not less
than the minimum shell thickness prescribed
in 6.7.2.4.3 and 6.7.2.4.4;

— "sandwich" construction, which means shells made with double walls having an intermediate layer
of rigid solid materials (e.g. foam, at least 50 mm thick), where the outer wall has a thickness of at
least 0,5 mm of steel, 0,8 mm of aluminium or 2 mm of a plastics material reinforced with glass
fibre. For other layer materials (e.g. mineral wool, at least 100 mm thick), the outer wall has a
thickness of at least 0,8 mm of austenitic steel. Other combinations of materials used to provide
protection against damage shall be shown to have equivalent strength. One method of comparing
the strength of sheets of materials is given in Annex B of EN 13094:2008.

5.4.2

For shells of road tank vehicles see also
6.9.2 of EN 13094:2008.

5.5 Protection of equipment
Items of equipment shall be protected against the risk of being wrenched off or damaged during
transport or handling.
For tanks other than rail tank wagons equipment
shall be protected by strengthening rings,
protective canopies or transverse or longitudinal
members. This protection of equipment shall
comply with 6.14 of EN 13094:2008.
Items of equipment of tank containers are
protected if placed within the contours of a

skeleton structure (frame).
Equipment used on tanks of tank vehicles for the
transport of substances to which the special
provision TE 19 of ADR (see subsection 6.8.4 ADR)
is allocated need additional protection.

10

RID/ADR 6.7.2.5 and 6.7.2.6 and 6.7.3.5 applies
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RID/ADR 6.8.2.2 applies also.
NOTE
For vacuum-operated
RID/ADR 6.10.3.1 applies.

waste

tanks


5.6 Oth er design requirements
Design criteria for:
— openings; see 6.3.5.1, 6.3.5.2.1 to 6.3.5.2.6, 6.3.5.3;
— ends; see 6.3.3.2 to 6.3.3.4;
— conical section of shell; see 6.3.4.1 and 6.3.4.2;
— hinged manhole cover and cover assemblies; see 6.3.6.5;
— flanges, joints and bolts; see 6.3.7.
NOTE 1
RID/ADR include requirements on - thermal insulation of linkage between shell and vehicle, design of
surge plates and partitions,- leakproof linings, thermal insulation, non- metallic linings, electrical earthing and
secure base and lifting devices (see RID/ADR 6.7.2, 6.7.3, 6.8.2.1.22, 6.8.2.1.24 – 6.8.2.1.27 and 6.8.5.1.5) which are
not considered in this standard.
NOTE 2
RID/ADR require that shells of portable tanks made from aluminium shall be insulated to prevent
significant loss of physical properties when subj ected to a heat load of 110 kW/m 2 for a period of not less than 3 0
min and that the insulation shall remain effective at all temperatures less than 649 °C and shall be jacketed with a
material with a melting point of not less than 700 °C.

6 Calculation
6.1 General
6.1.1 General
The minimum wall thickness of the tank shall be determined according to the calculation schemes of
6.1.2 and 6.1.3.
Additional thickness to allow for corrosion (progressive decrease of wall thickness) shall not be taken
into consideration in calculating the shell thickness.
The calculation schemes given in Figures 1 and 2 show how to determine the wall thickness of a shell to
meet the requirements of this standard and RID/ADR where Figure 1 applies to RID/ADR chapter 6.8
and Figure 2 applies to RID/ADR chapter 6.7.

6.1.2 Calculation scheme for the wall thickness of metallic pressure tanks of RID/AD R Chapter

6.8
The wall thickness chosen, shall not be less than the maximum value resulting from the wall thickness
determined according to branches A and B (RID/ADR 6.8.2) on the one hand and according to the
following formulae relevant to the test and service conditions (branches C and D) on the other.

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Figure 1 — Calculation scheme for the wall thickness of metallic pressure tanks of chapter 6.8 of
RID/ADR
6.1.3 Calculation scheme for the wall thickness of metallic portable pressure tanks of RID/ADR
chapte r 6.7
The wall thickness chosen, shall not be less than the maximum value resulting from the wall thickness
determined according to branch B (RID/ADR 6.7.2 and 6.7.3) on the one hand and according to the
following formulae relevant to the test and service conditions (branches C and D) on the other.

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Figure 2 — Calculation scheme for the wall thickness of metallic portable pressure tanks
of chapte r 6. 7 of RID/ADR

6.2 Design criteria
Design criteria (loads, allowable stresses, design temperature etc.) to be applied shall be taken from
Tables 1 and 2.

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Table 1 — Design criteria fo r chapte r 6. 8 tanks
Operating conditions

Test conditions


MWP

p test b

p

but not less than
(p vap − 1 bar) + p dyn if applicable a
fd for ferritic steels and
aluminium alloys

min { Re,t / 1,5; Rm / 2,4}

fd for austenitic steels
with 30 % ≤ A < 35 %

Re,t / 1,5

fd for austenitic steels
with A ≥ 35 %

max { Re,t / 1,5; min (Re,t / 1,2 ; Rm,t / 3)} c

Design temperature

20 °C provided that the operating
temperature of the tank is within the range
-20 °C to +50 °C. When the operating
temperature is outside this range then the

design temperature shall be taken as the
extreme value of the operating temperature.

min { 0,75 Re ; 0,5 Rm }

Temperature at the pressure test
(normally +20 °C).

a The dynamic forces shall be taken into account. This may be done by introducing an equivalent pressure p dyn determined
on the basis of the forces specified in RID/ADR 6.8.2.1 but not less than 35 kPa ( 0,35 bar) and add it to the vapour gauge
pressure (p vap – 1 bar) with . p vap not less than 1 bar. The largest compartment needs to be taken into account.
b To be taken from RID/ADR 6.8.2.4.1.
c It needs to be noted that the guaranteed minimum mechanical values differ with the temperature, and have to be chosen
accordingly. If no standard values are available, applicable values have to be determined otherwise.

Table 2 — Design criteria fo r chapte r 6. 7 tanks
Operating conditions

Test conditions

MAWP

p test b

p

but not less than
(p vap − 1 bar) + p dyn if applicable a
fd for ferritic steels and


aluminium alloys

fd for austenitic steels

with 30 % ≤ A < 35 %

fd for austenitic steels
with A ≥ 35 %

Design temperature

min { Re,t / 1,5; Rm / 2,4}
Re,t / 1,5

min { 0,75 Re ; 0,5 Rm }

max { Re,t / 1,5; min (Re,t / 1,2 ; Rm,t / 3)} c
20 °C provided that the operating
temperature of the tank is within the range
-40 °C to +50 °C. When the operating
temperature is outside this range then the
design temperature shall be taken as the
extreme value of the operating temperature.

Temperature at the pressure test
(normally +20 °C).

a The dynamic forces shall be taken into account. This may be done by introducing an equivalent pressure p dyn determined
on the basis of the forces specified in RID/ADR 6.7.2.2 and 6.7.3.2 respectively but not less than 35 kPa ( 0,35 bar) and add it to
the vapour gauge pressure (p vap – 1 bar) with . p vap not less than 1 bar. The largest compartment needs to be taken into account.

b To be taken from RID/ADR 6.7.2.3 and 6.7.3.3 respectively.
c It needs to be noted that the guaranteed minimum mechanical values differ with the temperature, and have to be chosen
accordingly. If no standard values are available, applicable values have to be determined otherwise.

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6.3 Calculation fo r internal pressure
6.3.1 General
The thickness of the cylindrical section of the shell shall be determined in accordance with 6.3.2. The
thickness of the ends (including partitions) of the shell shall be determined in accordance with 6.3.3.
The thickness of a conical section and the reinforcement of the cone to cylinder junction shall be
determined in accordance with 6.3.4. For flanges, joints and their bolts see 6.3.6.
Openings in the shell shall be designed in accordance with 6.3.5.
The calculation for construction types not given hereafter shall be in accordance with EN 13445-3.

6.3.2 Wall thickness of the cylindrical section
The wall thickness shall not be less than the value given by Formula (1).
e=

p × Di

2 fd × λ − p

(1)

6.3.3 Wall thickness of ends
6.3.3.1 General
The thickness of the ends, subject to the limitations in 6.3.3.2, shall not be less than that given by 6.3.3.3
and 6.3.3.4, 6.3.3.5 or 6.3.3.6 as applicable.

6.3.3.2 Design limitations
The following design limitations shall apply to the tank ends (compare Figure 3):
(a) Hemispherical ends

0,001 De

≤

e

≤

0,16 De

(b) Torispherical ends

0,001 De

≤

e


≤

0,08 De

0,06 Di

≤

r

≤

0,2 Di

r

≥

2e

R

≤

De

0,08 Di

(c) Ellipsoidal ends


0,001 Di

≤

e

≤

3,4

≤

Di /h ≤

4,4

The four relationships in (b) and the two relationships in (c) shall be simultaneously fulfilled.
NOTE

Kloepper and Korbbogen-type ends are particular cases of torispherical ends:

kloepper type
torispherical end for which R/ D e = 1,0 and r/ D e = 0,1

korbbogen type
torispherical end for which R/ D e = 0,8 and r/ D e = 0,154

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Figure 3 — Geometry of ends
6.3.3.3 Thickness of th e flange of the end
The wall thickness of the cylindrical or straight flange of the end shall not be less than the thickness as
determined in accordance with 6.3.2 for a cylindrical section having the same inside diameter Di .

6.3.3.4 Thickness of hemispherical ends
The thickness of a hemispherical end shall be not less than that determined by Formula (2) :
eR =

p × Di
4 fd × λ − p

(2)

6.3.3.5 Thickness of torispherical ends
6.3.3.5.1 General
The minimum thickness of torispherical ends shall be the greatest of the values of ey, es or eb as
determined by Formulae (3) to (5).
ey = β e


p ( 0,75 × R + 0, 2 × Di )
fd

(3)

where

βe is calculated from Formulae (6) to (14).
es =

p×R
2 fd × λ − 0,5 × p

 p  D  0, 825 
i

eb = ( 0,75 × R + 0, 2 × Di ) 
 1 1 1 fd  r 




(4)

(32 )

! deleted text"

where


eb is required thickness of knuckle to avoid plastic buckling;
es

is required thickness of end to limit membrane stress in central part;

ey is required thickness of knuckle to avoid axisymmetric yielding;
NOTE

16

It is not necessary to calculate eb if ey > 0,005 D i"

(5)


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It is permissible to reduce the thickness of the spherical part of the end to the value es over a circular
area that shall not come closer to the knuckle than the distance

R ⋅ e , as shown in Figure 3.

The right edge cylindrical flange shall meet the requirements of 6.3.2 for a cylinder, if its length is


D ⋅e.

greater than 0,2

When the length is equal or smaller than 0,2

i

D ⋅e ,
i

it may be the same

thickness as required for the knuckle.
If ends are manufactured from several elements then the welding coefficient λ may be taken equal to 1,0
(for thickness calculations only) if the weld crosses the crown area 0,6 De (see Figure 4).

λ = 0,8, 0,9 or 1,0

λ = 1,0

according to 7.4.3

λ = 1,0, λ = 0,8, 0,9 or 1,0

according to 7.4.3

a) we ld outside 0,6 De


b) weld insid e 0,6 De

c) composed ends

Figure 4 — Position of welds in ends
6.3.3.5.2 Formulae for calculation of β e

Y=
Z=

min (

l og

e R

1 0

/

(1 /

(6)

; 0, 0 4 )

Y

(7)


)

X=r D
/

N=

(8)

i

1, 0 0 6

−

(9)

1

6, 2

+

(90

Y

4

)


For X = 0,06:

β

e 0, 0 6

=

N

(

−

0, 3 6 3 5

Z

3

+

2, 2 1 2 4

Z

2

−


3, 2 9 3 7

Z+

1, 8 8 7 3 )

(10)

For 0,06 < X < 0,1:

β =
e

2 5 [( 0,1

−X β
)

e 0, 06

+

(

X−

0, 0 6 )

β


e 0, 1

]

(11)

For X = 0,1:

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β e 0,1 = N ( −0,1 833 Z 3 + 1,0383 Z 2 − 1, 2943 Z + 0,837 )

(12)

For 0,1 < X < 0,2:

β e = 1 0 [( 0, 2 − X ) β e 0,1 + ( X − 0,1 ) β e 0,2 ]

(13)


For X = 0,2:

β e 0, 2 = max { 0,95 ( 0,56 − 1,94 Y − 82,5 Y 2 ) ; 0,5 }

(14)

6.3.3.5.3 Openings within the knuckle area of Kloepper- and Korbbogen-type ends
6.3.3.5.3.1
In this clause rules are given for increasing the thickness of a dished end to compensate
for branches within the knuckle area.
The rules are limited in application to Kloepper- and Korbbogen-type ends for which:
di / De ≤ 0, 6
di
e × De

(15)

≤ 6,7

(16)

The increased thickness required by this clause applies to the whole knuckle area. Welded-on
compensation is not permitted.

6.3.3.5.3.2

Determine β k from the procedure in Table 3.

Replace p by (β k p ) in Formula (3) to arrive at the required thickness. Formulae (4) and (5) continue

and apply without modification.

Table 3 — Procedure fo r calculation of weakening factor β k
for openings in the knuckle region (design)
Step

Kloepper type end

1



V = log 1 0  1 000



p
fd





Korbbogen typ e end


V = log 1 0  1 000




p
fd





2

A = max { 0,5; 0, 264 + 0,938 V − 0,592 V 2 + 0,1 4 V 3 }

A = 0,54 + 0, 41 V − 0,044V 3

3

B = min { 4, 2 ; 4,91 − 2,1 65 V + 0,1 51 V 2 }

B = 7,77 − 4,53 V + 0,7441 V 2

4



β k = max  A + B


di
d 
; 1 + 0,3 B i 
De

De 



β k = max  A + B


di
d
; 1 + 0,5 B i
De
De





6.3.3.6 Thickness of ellipsoidal ends
An ellipsoidal end is an end that is made on a former that has a true ellipsoidal shape. Ellipsoidal ends
shall have a shape factor K with a value between 1,7 and 2,2.
K=

18

Di
2h

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Ellipsoidal ends shall be designed as torispherical ends in accordance with 6.3.3.5 with values of r and R
as given by the following:

r = 


R=

0, 5

K

−

( 0, 4 4

0, 0 8

K+






D

(18)

i

0, 0 2 )

D

i

(19)

6.3.4 Wall thickness of conical sections
6.3.4.1 General
The conical section of the shell shall conform to the design limitations in 6.3.4.2. The wall thickness shall
be determined in accordance with 6.3.4.3. For more information compare also EN 13445-3.

6.3.4.2 Design limitations of the conical section
This clause gives rules for right circular cones and cone/cylinder intersections where the cone and the
cylinder are of the same axis of rotation. It applies only to cones with an apex angle not greater than
120 ° and cones for which:

e×

co s


α

/

D

c

>

0, 0 0 1

(20)

For the angle α see Figure 5.
For offset cones between two cylinders the cylinders shall have parallel centrelines offset from each
other by a distance not greater than the difference of the radii. A required thickness shall be calculated
in accordance with 6.3.4.3.3 for the junction at the large end and in accordance with 6.3.4.3.4 for the
junction at the small end. Since the thickness calculated above is the minimum allowable at that point
along the case, it is permissible to build a cone from plates of different thickness provided that at every
point the minimum is achieved.

Figure 5 — Junction between cylinder and cone; angl e α
6.3.4.3 Determination of the wall thickness of the conical section
6.3.4.3.1

The minimum thickness of the wall of the conical section ek of the shell shall be not less than

the lowest value given by Formula (21) , unless otherwise required by the subclauses of 6.3.4.3.


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 p × Di
 1 
 
ek = 

 2 fd × λ − p   cos α 

6.3.4.3.2

(21)

Wall thickness at the junction of cylindrical and conical sections of the shell.

The conditions and design calculations for the large end of the cone are given in 6.3.4.3.3 and for the
small end of the cone in 6.3.4.3.4.

6.3.4.3.3


Large end of the cone without a knuckle at the joint.

The joint shall be made with a butt weld and there shall be a smooth transition across the joint from
cylindrical section to the conical section.
The minimum thickness of the wall of the shell at the junction of the conical and cylindrical sections
shall be determined from the following two formulae by iteration.
e1 =

p × Dc × β c
2 fd

(22)

 Dc  
tan α




3  e1   1 + 1 / cos α

1
β c= 


 − 0,1 5


(23)


This thickness shall be maintained for a distance of at least 1,4

1 ,

from the junction along the cylinder.

The required thickness e2 of the cone adjacent to the junction is the greater of e and ek. This thickness
shall be maintained for a distance of at least 1,4  2 from the junction along the cone, see Figure 5. The
distance

1

and  2 are determined as follows:

1

= Dc × e1

2

=

6.3.4.3.4

(24)

Dc × e2
cos α


(25)

Minimum thickness at the small end of the cone.

This clause applies provided that:
a)

junction is more than 2

1

along the cylinder and 2

1

along the cone from any other junction or

major discontinuity, such as another cone/cylinder junction or flange,
b)

minimum thickness of the cylinder e1 is maintained for a distance  1 and that of the cone e2 is
maintained for a distance

2

from the junction;

1

and  2 are calculated according to Formulae


(24) and (25) using Figure 6 and
c)

20

thickness meets the requirements of 6.3.2 and 6.3.4.3.1.


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Figure 6 — Geometry of cone/cylinder intersection; small end
Minimum thickness e1 and e2 shall be chosen so that:
e1 =

p × Dc × β H
2 fd × λ

(26)

where

β H = 0, 4


Dc tan α
×
+ 0,5
e1
t

(27)

t = S×

S
1 + S2
if S < 1
+
cos α
2

(28)

t =1 +

1 + S2
× S if S ≥ 1
2 cos α

(29)

e
S= 2

e1

(30)

NOTE

The above requirements do not provide values for e1 and e2 separately. They may have to be adjusted
relative to each other to suit the needs of the design.

6.3.5 Openings an d reinforcements
6.3.5.1 Openings in the shell
6.3.5.1.1 General.
Openings in the shell shall be either circular or elliptical. The size of the openings shall be not greater
than that given in 6.3.5.1.2. The distance between the openings shall not be less than that given in
6.3.5.1.3.
The ratio of major to minor axis of elliptical openings shall not exceed 2:1. The axis of elliptical openings
in the shell along the line of the shell shall be taken as the diameter of the opening for design purposes.
For elongated openings its larger length shall be taken as the diameter.
For calculation the ratio of the wall thickness of the branch to the wall thickness of the main body shall
comply with the limits of Figure 7.

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Figure 7 — Wall thickness rati o for branches
6.3.5.1.2 Size of openings in th e shell.
The size of the openings shall be not greater than the following:

d
D

i

≤

(31)

1

i

in the cylindrical sections;

d
D

i

≤

(32)


0, 6

i

in the dished ends.

6.3.5.1.3 Th e distance between openings.
The distance between openings when measured from the outside of the branch or the reinforcement, as
applicable, shall be no less than 2  m ,
where



where for shells

r

for torispherical ends

r

for elliptical ends

r

m

im


=
=

(2

r

im

+e

)

m

×e

(33)

m

D

(34)

i

2

im


=

R

im

=

D × 

(35)

i



0, 2 2

h

D

i

+

0, 0 2

(36)






where
em is the analysis thickness of the shell (end) maintained within the length  ;
m



m

is the length of the shell considered as effective compensation, measured along the material

centreline from the edge of the opening without a branch or outside of the branch (or pad).
For distances less than 2 

m

the remaining cross-section between openings shall be checked to ensure

that it is adequate to sustain the load acting on it (see also Formula (37) ).

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6.3.5.2 Nozzle reinforcement
6.3.5.2.1

The design method specified below only applies to cylindrical shells, and dished ends having
circular or elliptical openings, where the assumptions and conditions specified in 6.3.5.1 are satisfied.

6.3.5.2.2 Shells with openings shall be reinforced where necessary. The reinforcement of the main
body can be obtained by:
a)

set-in or set-on pads;

b)

set-in or set-on branches; or

c)

combinations thereof.

6.3.5.2.3

The reinforcement area of the main body with openings cannot be calculated directly but
shall be assumed in the first instance. This assumption may be verified by means of the following

method. The applied method is based on basic pressure thicknesses derived from formulae in 6.3.2 for
cylindrical shells and from formulae in 6.3.3 for dished ends and leads to relationships between a
pressure loaded area A p and a stress loaded cross sectional area which is the sum of A fm , A fp and A fb

(see Figure 8). The calculation may need to be repeated using a corrected assumption of the
reinforcement area.

6.3.5.2.4

Where necessary, sufficient reinforcement shall be provided in all planes through the axis of
the opening branch.

6.3.5.2.5

In the case of elliptical openings the ratio between the major and the minor axis shall not
exceed 2. For elliptical openings in cylindrical shells the opening axis parallel to the longitudinal axis of
the cylinder shall be taken as the diameter for design purposes. For elliptical openings in dished ends
the major axis shall be so taken.

6.3.5.2.6

Set-in or set-on fillet welded branches shall only be considered in the calculation if the ratio
of the diameter is di / De ≤ 1/3 and the ratio of the wall thickness eb / em is less than 0,7. Each fillet weld

shall have a throat thickness not less than 0,7 times the thinner wall thickness.

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