oSIST prEN 12285-4:2022
(Main)Workshop fabricated steel tanks - Part 4: Vertical cylindrical single skin and double skin tanks for the aboveground storage of flammable and nonflammable water polluting liquids other than for heating and cooling of buildings
Workshop fabricated steel tanks - Part 4: Vertical cylindrical single skin and double skin tanks for the aboveground storage of flammable and nonflammable water polluting liquids other than for heating and cooling of buildings
This document specifies the requirements for metallic shop fabricated shop fabricated cylindrical vertical steel tanks, single and double skin for the aboveground storage of water polluting liquids (both flammable and non-flammable) within the following limits:
• from Ø 1250 mm up to Ø 4 000 mm inner tank nominal diameter and,
• up to maximum overall length of 6 times the nominal inner tank diameter and
• tank possible to be divided from 1 to 5 compartments
• for liquids with maximum density of up to 1,9 kg/l and,
• with an operating pressure (P0) of maximum 50kPa (0,5 bar (g)) and minimum – 5 kPa (- 50 mbar (g)) and,
• where double skin tanks with vacuum leak detection system are used the cinematic viscosity of the stored media shall not exceed 5 x 10-3 m²/s
This document is applicable for normal ambient temperature conditions (-40 °C to + 50 °C). Where temperatures are outside this range, additional requirements need to be taken into account.
This document is not applicable to tanks used for storage and/or supply of fuel/gas for building heating/cooling systems, and of hot or cold water not intended for human consumption, nor to loads and special measures necessary in areas subject to risk of earthquakes.
This document is not applicable for the storage of liquids having dangerous goods classes listed in Table 1 because of the special dangers involved.
Table 1 — List of dangerous goods which are not covered by this standard
UN-classification Type of dangerous goods
Class 1 Explosives
Class 4.2 Substances liable to spontaneous combustion
Class 4.3 Substances which in contact with water emit flammable gases
Class 5.2 Organic peroxides
Class 6.2 Infectious substances
Class 7 Radioactive substances, hydrocyanic or hydrocyanic solvent liquids, metal carbons, hydrofluoric acid, bromide liquids
NOTE The classifications referred to are those adopted by the United Nations Committee of Experts on the Transport of Dangerous Goods (not to be interpreted as tank classes described in 6.2).
Werksgefertigte Tanks aus Stahl - Teil 4: Vertikale zylindrische Metalltanks mit ein- und doppelwandiger Hülle zur oberirdischen Lagerung von brennbaren und nicht brennbaren wassergefährdenden Flüssigkeiten, die nicht zum Heizen oder Kühlen von Gebäuden bestimmt sind
Dieses Dokument legt die Anforderungen an werksgefertigte, zylindrische, vertikale Stahltanks mit ein- und doppelwandiger Hülle zur oberirdischen Lagerung (brennbarer und nicht brennbarer) wassergefährdender Flüssigkeiten mit folgenden Anwendungsgrenzen fest:
Nenn-Innendurchmesser des Tanks im Bereich von 1 250 mm bis 4 000 mm; und
maximale Gesamtlänge des Manteils bis zum 6-Fachen des Nenn-Innendurchmessers des Tanks (oder einer maximalen Mantellänge Lz von 14 m); und
der Möglichkeit, den Tank in 1 bis 5 Tankkammern zu unterteilen;
für Flüssigkeiten mit einer maximalen Dichte von 1,9 kg/l; und
mit einem Betriebsdruck (po) von höchstens 50 kPa (0,5 bar(g)) und mindestens −5 kPa (−50 mbar(g)); und
bei der Nutzung von doppelwandigen Tanks mit Unterdruck-Leckanzeigesystemen darf die kinematische Viskosität der Lagermedien (5 × 10−3) m2/s nicht überschreiten.
Dieses Dokument ist unter den Umgebungstemperaturbedingungen des Normalklimas (d. h. im Bereich von −40 °C bis +50 °C) anwendbar. Bei Temperaturen außerhalb dieses Bereichs ist es notwendig, zusätzliche Anforderungen zu beachten.
Dieses Dokument ist nicht auf Tanks anwendbar, die für die Lagerung und/oder Bereitstellung von Brennstoff/Gas für Heiz-/Kühlsysteme von Gebäuden und von nicht für den menschlichen Gebrauch bestimmtem Warm- oder Kaltwasser genutzt werden, und gilt auch nicht für die in erdbebengefährdeten Gebieten anfallenden Lasten und die dafür notwendigen besonderen Maßnahmen.
Dieses Dokument gilt wegen der besonderen damit verbundenen Gefahren nicht für die Lagerung von Flüssigkeiten der in Tabelle 1 aufgeführten Gefahrgutklassen.
Tabelle 1 - Liste von Gefahrgütern, die von diesem Dokument nicht abgedeckt werden
UN-Klassifizierung Gefahrgüter vom Typ
Klasse 1 Explosive Stoffe
Klasse 4.2 Selbstentzündliche Stoffe
Klasse 4.3 Stoffe, die in Berührung mit Wasser entzündliche Gase bilden
Klasse 5.2 Organische Peroxide
Klasse 6.2 Ansteckungsgefährliche Stoffe
Klasse 7 Radioaktive Stoffe, blausäurehaltige oder blausäurelösliche Flüssigkeiten, Metallkohlenstoffe, Flusssäure, bromhaltige Flüssigkeiten
ANMERKUNG Die hier in Bezug genommenen Klassifizierungen sind die vom Fachausschuss der Vereinten Nationen für die Beförderung gefährlicher Güter angenommenen Klassifizierungen (und sind nicht als die in 6.2 beschriebenen Tankklassen zu verstehen).
Réservoirs en acier fabriqués en atelier - Réservoirs verticaux cylindriques à simple et double paroi pour le stockage aérien de liquides inflammables et non inflammables polluant l'eau, en dehors du chauffage et du refroidissement des bâtiments
Le présent document spécifie les prescriptions pour les réservoirs en acier verticaux cylindriques fabriqués en atelier, à simple et double paroi pour le stockage aérien de liquides polluant l’eau (inflammables et non inflammables) dans les limites suivantes :
— diamètre nominal du réservoir intérieur de Ø 1 250 mm jusqu’à Ø 4 000 mm et ;
— longueur maximale d’encombrement de la virole égale à 6 fois le diamètre nominal du réservoir intérieur (ou 14 m maximum pour la longueur de la virole Lz), et
— possibilité pour un réservoir d’être divisé de 1 à 5 compartiments
— pour les liquides présentant une masse volumique maximale égale à 1,9 kg/l et
— avec une pression de service (P0) maximale de 50 kPa (0,5 bar (g)) et une pression de service minimale de – 5 kPa (– 50 mbar(g)) ; et
— lorsque des réservoirs à double paroi avec un système de détection de fuites du vide sont utilisés, la viscosité cinématique des fluides stockés ne doit pas dépasser 5 x 10‐3 m²/s.
Le présent document s’applique à des conditions de température ambiante normales (-40 °C à + 50 °C). Lorsque les températures sont à l’extérieur de cette plage, des prescriptions complémentaires doivent être prises en compte.
Le présent document ne s’applique pas aux réservoirs utilisés pour le stockage et/ou l’alimentation en combustible/gaz des systèmes de chauffage/refroidissement des bâtiments, et en eau chaude ou froide non destinée à la consommation humaine, ni aux charges et mesures spéciales nécessaires dans les zones exposées à un risque sismique.
Le présent document ne s’applique pas au stockage de liquides relevant des classes de matières dangereuses énumérées au Tableau 1, en raison des dangers spécifiques pouvant être engendrés.
Tableau 1 - Liste des matières dangereuses non couvertes par le présent document
Classification de l’ONU Type de matières dangereuses
Classe 1 Explosifs
Classe 4.2 Substances sujettes à une combustion spontanée
Classe 4.3 Substances émettant des gaz inflammables au contact de l’eau
Classe 5.2 Peroxydes organiques
Classe 6.2 Substances infectieuses
Classe 7 Substances radioactives, liquides ou solvants cyanhydriques, métal-carbones, acide fluorhydrique, liquides bromhydriques
NOTE Les classifications données en référence sont celles adoptées par le Comité d’experts des Nations Unies pour le Transport des Matières dangereuses (elles ne doivent pas être interprétées comme les classes de réservoirs décrites en 6.2)
V delavnici izdelani jekleni rezervoarji - 4. del: Enoplaščni in dvoplaščni pokončni valjasti rezervoarji za nadzemno skladiščenje gorljivih in negorljivih tekočin, ki onesnažujejo vodo in ki se ne uporabljajo za ogrevanje in hlajenje stavb
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN 12285-4:2022
01-julij-2022
[Not translated]
Workshop fabricated steel tanks - Part 4: Vertical cylindrical single skin and double skin
tanks for the aboveground storage of flammable and nonflammable water polluting
liquids other than for heating and cooling of buildings
Werksgefertigte zylindrische vertikale Metalltanks mit ein- und doppelwandiger Hülle zur
Lagerung von brennbaren und nicht brennbaren wassergefährdenden Flüssigkeiten
Ta slovenski standard je istoveten z: prEN 12285-4
ICS:
13.300 Varstvo pred nevarnimi Protection against dangerous
izdelki goods
23.020.10 Nepremične posode in Stationary containers and
rezervoarji tanks
oSIST prEN 12285-4:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN 12285-4:2022
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oSIST prEN 12285-4:2022
DRAFT
EUROPEAN STANDARD
prEN 12285-4
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2022
ICS 13.300; 23.020.10
English Version
Workshop fabricated steel tanks - Part 4: Vertical
cylindrical single skin and double skin tanks for the
aboveground storage of flammable and nonflammable
water polluting liquids other than for heating and cooling
of buildings
Werksgefertigte zylindrische vertikale Metalltanks mit
ein- und doppelwandiger Hülle zur Lagerung von
brennbaren und nicht brennbaren
wassergefährdenden Flüssigkeiten
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 265.
If this draft becomes a European Standard, 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.
This draft European Standard was established by CEN 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12285-4:2022 E
worldwide for CEN national Members.
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Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 6
3 Terms, definitions, symbols, and abbreviations . 6
3.1 Terms and definitions . 6
3.2 Symbols and abbreviations . 10
4 Product characteristics . 12
4.1 General . 12
4.2 Welding . 12
4.2.1 Types of joints . 12
4.2.2 Shell plate arrangement . 14
4.2.3 Consumables . 14
4.2.4 Interstitial space . 14
4.3 Load bearing capacity . 16
4.4 Additional requirements . 16
4.4.1 Manways . 16
4.4.2 Structural bolts . 17
4.4.3 Tank fittings, pipes and nozzles . 17
4.4.4 Lifting lugs . 19
4.4.5 Tank leg construction . 19
4.5 Tank compartments . 21
4.6 Tank pipes . 21
4.6.1 General . 21
4.6.2 Vent pipes . 21
4.6.3 Suction pipes . 21
4.6.4 Fill pipes . 22
4.7 Mechanical resistance and stability . 22
4.7.1 Materials for shell, dished ends and manways . 22
4.7.2 Wall thickness . 22
4.8 Internal pressure . 24
4.9 Tightness (gas and liquid). 24
4.10 Release of dangerous substances . 24
4.11 Coating . 24
5 Testing and sampling methods . 24
5.1 Mechanical resistance and stability . 24
5.1.1 Materials for shell, dished ends and manways . 24
5.1.2 Wall thickness . 24
5.1.3 Welding . 25
5.1.4 Tank leg construction . 25
5.2 Tightness test (gas or liquid) . 25
5.3 Testing of additional requirements . 25
5.3.1 Manways and inspection covers . 25
5.3.2 Structural bolts . 25
5.3.3 Tank fittings, pipes and nozzles . 25
2
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5.3.4 Lifting lugs . 26
5.4 Durability. 26
6 Classification . 26
6.1 Tank type . 26
6.2 Tank classes . 26
6.3 Designation and purchaser's specification . 26
7 Marking and labelling . 27
7.1 Marking of the tank . 27
7.2 Documentation . 27
8 Environmental aspects . 27
Annex A (informative) Tank installation and use . 28
A.1 Transport . 28
A.2 Installation procedure . 28
A.3 Maintenance . 28
Annex B (informative) Environmental aspects . 29
Bibliography . 31
3
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European foreword
This document (prEN 12285-4:2022) has been prepared by Technical Committee CEN/TC 265 “Metallic
tanks for the storage of liquids”, the secretariat of which is held by BSI.
This document is currently submitted to the CEN Enquiry.
4
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1 Scope
This document specifies the requirements for metallic shop fabricated cylindrical vertical steel tanks,
single and double skin for the aboveground storage of water polluting liquids (both flammable and non-
flammable) within the following limits:
— from Ø 1250 mm up to Ø 4 000 mm inner tank nominal diameter, and
— up to maximum overall shell length of 6 times the nominal inner tank diameter (or max 14 m shell
lenght Lz), and
— tank possible to be divided from 1 to 5 compartments,
— for liquids with maximum density of up to 1,9 kg/l, and
— with an operating pressure (P ) of maximum 50kPa (0,5 bar (g)) and minimum – 5 kPa (- 50 mbar
0
(g)), and
— where double skin tanks with vacuum leak detection system are used the kinematic viscosity of the
−3 2
stored media shall not exceed 5 × 10 m /s.
This document is applicable for normal ambient temperature conditions (−40 °C to + 50 °C). Where
temperatures are outside this range, additional requirements need to be taken into account.
This document is not applicable to tanks used for storage and/or supply of fuel/gas for building
heating/cooling systems, and of hot or cold water not intended for human consumption, nor to loads and
special measures necessary in areas subject to risk of earthquakes.
This document is not applicable for the storage of liquids having dangerous goods classes listed in Table 1
because of the special dangers involved.
Table 1 — List of dangerous goods which are not covered by this document
UN-classification Type of dangerous goods
Class 1 Explosives
Class 4.2 Substances liable to spontaneous combustion
Class 4.3 Substances which in contact with water emit flammable gases
Class 5.2 Organic peroxides
Class 6.2 Infectious substances
Class 7 Radioactive substances, hydrocyanic or hydrocyanic solvent liquids, metal
carbons, hydrofluoric acid, bromide liquids
NOTE The classifications referred to are those adopted by the United Nations Committee of Experts on the
Transport of Dangerous Goods (not to be interpreted as tank classes described in 6.2).
5
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2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 10025-2:2019, Hot rolled products of structural steels – Part 2: Technical delivery conditions for non-
alloy structural steels
EN 10204:2004, Metallic products - Types of inspection documents
EN 13160-1, Leak detection systems - Part 1: General Principles
EN 13160-2, Leak detection systems - Part 2: Requirements and test/assessment methods for pressure and
vacuum systems
EN 13160-3, Leak detection systems - Part 2: Requirements and test/assessment methods for pressure and
vacuum systems
EN 13160-4, Leak detection systems - Part 4: Requirements and test/assessment methods for sensor based
leak detection systems
EN 22768 series, General tolerances (ISO 2768 series)
EN ISO 898-1, Mechanical properties of fasteners made of carbon steel and alloy steel - Part 1: Bolts, screws
and studs with specified property classes - Coarse thread and fine pitch thread (ISO 898-1)
EN 13616-1, Overfill prevention devices for static tanks for liquid fuels - Part 1: Overfill prevention devices
with closure device
EN 13616-2, Overfill prevention devices for static tanks for liquid fuels - Part 2: Overfill prevention devices
without a closure device
EN ISO 13920, Welding - General tolerances for welded constructions - Dimensions for lengths and angles -
Shape and position (ISO 13920)
3 Terms, definitions, symbols, and abbreviations
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at https://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
tank
workshop fabricated cylindrical containment for the storage of liquids
Note 1 to entry: Tanks are made of steel plates, equipped with dished ends and consist of one or more
compartments.
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3.1.2
compartment
single fluid storage space within a tank
3.1.3
single skin tank
impermeable containment consisting of a self-contained/ self supported tank of single containment
Note 1 to entry: A single skin tank also constitutes the inner skin of a double skin tank. See Figure 1 and Figure 2.
Note 2 to entry: See Figure 1.
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Key
1 max compartment liquid level on normal pipe connection
2 above liquid level single skin
Figure 1 — Example of tank symbols for double skin tank
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Key
1 Ring to ensure proper painting. Venting hole needed on the ring for ensuring vapors to vent and for pressure
testing.
Figure 2 — Example of tank symbols for single skin tank
3.1.4
double skin tank
impermeable self-contained tank with outer skin welded around the inner tank
Note 1 to entry: See Figure 1.
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3.1.5
operating pressure
p
o
pressure bar(g) inside the tank above the liquid during operating conditions
3.1.6
prototype tank test pressure
p
t1
pressure bar(g) to which the tank or compartment is subjected for testing
3.1.7
prototype interstitial space test pressure
p
t2
pressure bar(g) to which the interstitial space between the skins is subjected for testing
Note 1 to entry: Only applicable for double skin tanks.
3.1.8
tank leak tightness test pressure
p
t3
pressure bar(g) to which the tank or compartment is subjected to leak testing
3.1.9
interstitial space leak tight test pressure
pt
4
pressure bar(g) to which the interstitial space is subjected to leak testing
3.1.10
nominal volume
storage capacity for which the tank is designed
3.1.11
actual volume
volume which is equal to or greater than the nominal volume
3.2 Symbols and abbreviations
For the purpose of this document the following symbols apply.
Dimensions in millimetres
a dimension for welding (See Figure 2)
d external nominal diameter of the tank
1
d internal diameter of the manway
2
d diameter of the manway cover and corresponding flange
3
d internal diameter of the outer manway
4
d diameter of the outer manway cover and corresponding flange
5
h length of the straight flange of the dished end
1
10
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H Height of the tank leg construction
L
Height of spill bund to interstitial space
H
b
Height of bottom cone to ground
H
c
K pitch circle diameter of manway bolts
p
K pitch circle diameter of outer manway bolts
p2
l length of the compartment of a tank without dished ends
c
NOTE 1 For a single compartment tank Lc = Lz
l overall length of the tank, from ground to top manway
o
l length of the tank without dished ends
z
NOTE 2 For a single compartment tank Lc = Lz
p test pressure
t
p test pressure for prototype test of tank
t1
p test pressure of prototype test of interstitial space
t2
p test pressure of leak tightness test of tank
t3
p test pressure of leak tightness test of interstitial space
t4
r crown radius of dished ends
1
r knuckle radius of dished ends
2
s nominal thickness of shell (single walled tank) and inner shell (double walled tank)
1
s interstitial space
2
s nominal thickness of outer shell
3
s nominal thickness of outer dished ends
4
s nominal thickness of compartment dished ends
5
s nominal thickness of manway flange and cover
6
s plate thickness of manway body
7
s nominal thickness of inner dished ends
8
s
nominal thickness of secondary manway flange and cover
9
s plate thickness of secondary manway body
10
s nominal thickness of tank leg shell
11
s nominal thickness of tank outer shell installation ring (Tickness s is greater or equal to s )
12 12 3
γ incline angle for T-joint welding
11
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4 Product characteristics
4.1 General
The tank material shall be suitable for long term contact with the stored media. Guidelines on material
specifications in relation to stored media are provided in EN 12285-1:2018, Annex B.
The safe working capacity of the tank should usually not exceed 95 % of the nominal volume at normal
operating temperatures.
4.2 Welding
4.2.1 Types of joints
The welding related to the different types of joints is given in Table 2. The types of welded joints shall be
in accordance with Table 2.
Table 2 — Types of welded joints
Number Types of joints Applicable welding class of tanks and liquid
(liquid touched wall)
Plate misalignment shall not exceed 0,3 s
1 Square butt joint
1
respectively 0,3 s or 2 mm
3
For all classes
2a Joggled butt joint For class A and hydrocarbon liquids
For double and single skin tanks
Not permissible with inner coating
2b Joggled butt joint For class A, B and C
3a Overlap joint For class A, B and C
For outer skin only
a = 0,7 s
3
3b Overlap joint For class A, B and C
For outer skin on outer dished end only
a = 0,7 s
3
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Number Types of joints Applicable welding class of tanks and liquid
(liquid touched wall)
4 Fillet weld in T-joint For class A, B and C
For nozzles and manways in the outer skin
a = 0,7 s
min
s : thickness of the thinner plate
min
5 Fillet weld (full penetration) in T- For class A, B and C
joint
For manways, nozzles and inspection covers
γ = 45°
6 Double fillet weld in T-joint For class A, B and C
For manways, nozzles and stiffening rings
a = 0,7 s
min
s = thickness of the thinner plate
min
7a Fillet weld in overlap joint For class A, B and C
For compartment dished ends with knuckle radius
7b Fillet weld in overlap joint For class A, B and C
For compartment dished ends with knuckle radius
Not permissible with inner coating
8 Butt joint For class A and B
For compartment dished ends with knuckle radius
Not permissible with inner coating
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Number Types of joints Applicable welding class of tanks and liquid
(liquid touched wall)
9 Double fillet weld in T-joint For class A and B
For compartment dished ends without knuckle
radius
a = 0,7 s
5
10 Corner and fillet weld For class A and B
For set-on manways and nozzles
4.2.2 Shell plate arrangement
Cross seams shall not be used.
Shell plate joints shall be offset, having a minimum distance e of five times the wall thickness but not less
than 100 mm as shown in Figure 2.
Figure 3 — Shell-plate arrangement for inner and outer skin
Key
e minimum distance
4.2.3 Consumables
All welding rods/wires and other consumables shall be compatible with the basic material.
4.2.4 Interstitial space
The interstial cap should be suitable for leak detection selected and can be used for other needed
functions as heating, insulation, cooling, or safety equipments needed.
The interstitial space shall cover any tank manway connections that are below the liquid level.
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Leak detection systems should comply with EN 13160-2 Class 1 Vaccum using air, EN 13160-4, Class 3
by using liquid level or vapor indicator.
When using a Class 3 system, the interstitial space needs a venting pipe on the top point of the tank.
The connection from double skin manway needs to be open to interstital space, but on the lower part
needs to be a minimum of 30 mm height of spill bund to interstitial space (H ) to prevent possible small
b
spill to go to interstitial space when opening the inner manway.
Figure 4 — Structure of double skin manway
There shall be at least two sockets for the leak detection system, and these shall be located at the highest
point of the interstitial space and on the lowest point of interstitial space to enable draining of the
interstitial space if needed.
The interstitial space shall be connected to a leak detection system in order to monitor the integrity of
the tank permanently; the leak detection system shall fulfil the requirements of EN 13160-1 to
EN 13160-4.
Interstitial space shall be designed to enable the full tank volume to be stored. This can be regulated by
local regulations.
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When constructing a larger interstital space the support structure of the outer skin shall be designed to
carry lifts and loads of the tank handling and use.
4.3 Load bearing capacity
When tested in accordance with 5.2, the maximum out of roundness of the completed tank after
manufacture shall not exceed 1,5 % of the diameter.
The tolerance on the overall length of the tank shall be ± 1 % of the real length stated by the manufacturer.
4.4 Additional requirements
4.4.1 Manways
The tank compartments shall have at least one manway of min. d = 600 mm.
2
Manways, inspection covers, nozzles and/or flanges shall be of set-through or set-on-type and flanges
shall be welded in accordance with Table 2.
For the dimensions of the manways and their components see Table 3.
Gaskets shall be provided and shall be suitable for their purpose.
Table 3 — Dimensions of manway components
Inside Plate Diameter Pitch circle Bolt hole Flange thickness Bolts
diameter thickness of manway diameter diameter and cover
of cover and thickness
manway correspond
body ing flange
Thread
d s d K mm s Number
2 7 3 p 6
size
mm mm mm mm mm
Class A Class B
and C
a
6 720 680 12 16 32
600
800 7 920 880 18 12 20 M16 44
b
7 1 120 1 080 — 20 48
1000
a
If a manway is required and no specification is given by the purchaser this diameter shall be used.
b
For tanks of class C inside diameters of the manway (d2) exceeding 800 mm is not permitted.
Instead of the manway covers shown in the Figure 3 and dimensioned in Table 3, pressed parts of
manways (covers and/or nozzles) may be used in class A tanks with a plate thickness at least equal to the
thickness of the inner tank s .
1
The gasket shall be in one piece.
For inspection covers for tanks of class A with d ≤ 1250 mm and tanks of classes B and C with
1
d ≤ 1000 mm, the diameter of the inspection cover shall not be more than 300 mm and not less than
1
120 mm, and the thickness of the inspection cover shall be equal to the minimum thickness of the inner
tank.
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oSIST prEN 12285-4:2022
prEN 12285-4:2022 (E)
Table 4 — Secondary cover dimensions, for manway below the liquid level at tank for double
skin tank
Inside Plate Diameter of Pitch Bolt hole Flange Bolts
diameter thickness manway cover circle diameter thickness and
of and diameter cover thickness
manway corresponding
body flange
d s d K mm s Thread Number
4 10 5 p2 9
size
mm mm mm mm mm
Class A Class B
and C
a
4 920 880 10 12 32
800
1000 5 1120 1080 14 12 20 M12 44
a
If a manway is required and no specification is given by the purchaser this diameter shall be used.
b
For tanks of class C inside diameters of the manway (d2) exceeding 800 mm is not permitted.
4.4.2 Structural bolts
Structural bolts used shall be in accordance with EN ISO 898-1, with a property class of at least 6.8.
4.4.3 Tank fittings, pipes and nozzles
Materials used for the fabrication of
...
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