Cryogenic vessels - Pumps for cryogenic service (ISO 24490:2016)

This standard specifies the minimum requirements for the design, manufacture and testing of pumps for cryogenic service (i.e. for operation with cryogenic fluids below -10°C). This standard covers centrifugal pumps. However the principles may be applied to other types of pumps (e.g. reciprocating). This standard also gives guidance on the design of installations. (See annex A). It does not specify requirements on operation or maintenance.

Kryo-Behälter - Pumpen für den Kryo-Betrieb (ISO 24490:2016)

Diese Internationale Norm legt die Mindestanforderungen für die Auslegung, die Fertigung, und die Prüfung von Pumpen für den Kryo Betrieb fest.
Diese Internationale Norm gilt für Kreiselpumpen. Sie kann jedoch, sofern zutreffend, auch für andere Pumpenbauarten (z. B. Kolbenpumpen) angewendet werden.
Diese Internationale Norm enthält auch Anleitungen zur Auslegung von Anlagen (siehe Anhang A).
Sie legt keine Anforderungen an Betrieb oder Instandhaltung fest.

Récipients cryogéniques - Pompes pour service cryogénique (ISO 24490:2016)

ISO 24490:2016 spécifie les exigences minimales en matière de conception, de fabrication et d'essais des pompes pour service cryogénique.
ISO 24490:2016 s'applique aux pompes centrifuges. Le cas échéant, elle peut toutefois être appliquée à d'autres types de pompes cryogéniques (pompes à piston, par exemple).
La présente Norme internationale donne également des préconisations pour la conception des installations (voir l'Annexe A).
Elle ne spécifie aucune exigence relative au fonctionnement ou à la maintenance.
NOTE          Pour les fluides cryogéniques, voir l'ISO 21029‑1, l'ISO 20421‑1 et/ou l'ISO 21009‑1.

Kriogene posode - Črpalke za kriogeno področje (ISO 24490:2016)

Ta standard določa minimalne zahteve za načrtovanje, izdelavo in preskušanje črpalk za kriogeno področje (t.j. za delo s kriogenimi tekočinami pod –10 °C). Ta standard zajema centrifugalne črpalke. Načela iz tega standarda se lahko uporabijo za druge vrste črpalk (npr. batne črpalke). Ta standard podaja tudi smernice glede načrtovanja objektov (glej dodatek A). Standard ne določa zahtev za obratovanje ali vzdrževanje.

General Information

Status
Published
Public Enquiry End Date
09-Jun-2015
Publication Date
17-Apr-2017
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
02-Feb-2017
Due Date
09-Apr-2017
Completion Date
18-Apr-2017

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 24490:2017
01-maj-2017
1DGRPHãþD
SIST EN 13275:2001
.ULRJHQHSRVRGHýUSDONH]DNULRJHQRSRGURþMH ,62
Cryogenic vessels - Pumps for cryogenic service (ISO 24490:2016)
Kryo-Behälter - Pumpen für den Kryo-Betrieb (ISO 24490:2016)
Récipients cryogéniques - Pompes pour service cryogénique (ISO 24490:2016)
Ta slovenski standard je istoveten z: EN ISO 24490:2016
ICS:
23.020.40 Proti mrazu odporne posode Cryogenic vessels
(kriogenske posode)
23.080 ýUSDONH Pumps
SIST EN ISO 24490:2017 en,fr,de

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

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SIST EN ISO 24490:2017
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SIST EN ISO 24490:2017
EN ISO 24490
EUROPEAN STANDARD
NORME EUROPÉENNE
April 2016
EUROPÄISCHE NORM
ICS 23.020.40 Supersedes EN 13275:2000
English Version
Cryogenic vessels - Pumps for cryogenic service (ISO
24490:2016)

Récipients cryogéniques - Pompes pour service Kryo-Behälter - Pumpen für den Kryo-Betrieb (ISO

cryogénique (ISO 24490:2016) 24490:2016)
This European Standard was approved by CEN on 15 March 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
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 24490:2016 E

worldwide for CEN national Members.
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SIST EN ISO 24490:2017
EN ISO 24490:2016 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO 24490:2017
EN ISO 24490:2016 (E)
European foreword
This document (EN ISO 24490:2016) has been prepared by Technical Committee

ISO/TC 220 “Cryogenic vessels” in collaboration with Technical Committee CEN/TC 268 “Cryogenic

vessels and specific hydrogen technologies applications” 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 October 2016, and conflicting national standards shall

be withdrawn at the latest by October 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 supersedes EN 13275:2000.

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.
Endorsement notice

The text of ISO 24490:2016 has been approved by CEN as EN ISO 24490:2016 without any modification.

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SIST EN ISO 24490:2017
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SIST EN ISO 24490:2017
INTERNATIONAL ISO
STANDARD 24490
Second edition
2016-03-15
Cryogenic vessels — Pumps for
cryogenic service
Récipients cryogéniques — Pompes pour service cryogénique
Reference number
ISO 24490:2016(E)
ISO 2016
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SIST EN ISO 24490:2017
ISO 24490:2016(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form

or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior

written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of

the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2016 – All rights reserved
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SIST EN ISO 24490:2017
ISO 24490:2016(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Requirements for pumps ............................................................................................................................................................................. 2

4.1 General ........................................................................................................................................................................................................... 2

4.2 Materials ....................................................................................................................................................................................................... 2

4.2.1 General...................................................................................................................................................................................... 2

4.2.2 Mechanical properties at low temperature .............................................................................................. 2

4.2.3 Corrosion resistance ..................................................................................................................................................... 3

4.2.4 Oxygen and oxidizing fluids compatibility ................................................................................................ 3

4.2.5 Hydrogen compatibility ............................................................................................................................................. 4

4.3 Design ............................................................................................................................................................................................................. 4

4.3.1 Pressure-containing parts ....................................................................................................................................... 4

4.3.2 Performance ........................................................................................................................................................................ 4

4.3.3 Clearances .............................................................................................................................................................................. 4

4.3.4 Prevention of rubbing.................................................................................................................................................. 4

4.3.5 Fastenings .............................................................................................................................................................................. 4

4.3.6 Warm bearings .................................................................................................................................................................. 4

4.3.7 Cold bearings ...................................................................................................................................................................... 4

4.3.8 Bearing lubrication ........................................................................................................................................................ 5

4.3.9 Shaft seals .............................................................................................................................................................................. 5

4.3.10 Purging ..................................................................................................................................................................................... 5

4.3.11 Prevention of particle contamination ............................................................................................................ 5

4.3.12 Specific requirement for flammable liquids ............................................................................................. 5

4.3.13 Protection against over-pressurization ....................................................................................................... 6

4.3.14 Pump motors ....................................................................................................................................................................... 6

5 Test procedures ..................................................................................................................................................................................................... 6

5.1 Prototype testing ................................................................................................................................................................................... 6

5.1.1 General...................................................................................................................................................................................... 6

5.1.2 Design evaluation ............................................................................................................................................................ 6

5.1.3 Performance evaluation............................................................................................................................................. 6

5.1.4 Initial tests ............................................................................................................................................................................. 6

5.1.5 Cryogenic tests................................................................................................................................................................... 7

5.2 Production testing ................................................................................................................................................................................ 7

5.2.1 General...................................................................................................................................................................................... 7

5.2.2 Hydrostatic pressure test ......................................................................................................................................... 7

5.2.3 Mechanical running and performance test ............................................................................................... 8

6 Cleanliness .................................................................................................................................................................................................................. 8

7 Marking .......................................................................................................................................................................................................................... 8

Annex A (informative) Guidance on installation design .................................................................................................................. 9

Annex B (informative) Acceptable materials for construction of centrifugal pumps for

liquid oxygen .........................................................................................................................................................................................................11

Bibliography .............................................................................................................................................................................................................................15

© ISO 2016 – All rights reserved iii
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SIST EN ISO 24490:2017
ISO 24490:2016(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

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

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation on the meaning of ISO specific terms and expressions related to conformity

assessment, as well as information about ISO’s adherence to the WTO principles in the Technical

Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information

The committee responsible for this document is ISO/TC 220, Cryogenic vessels.

This second edition cancels and replaces the first edition (ISO 24490:2005), which has been technically

revised.
iv © ISO 2016 – All rights reserved
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SIST EN ISO 24490:2017
INTERNATIONAL STANDARD ISO 24490:2016(E)
Cryogenic vessels — Pumps for cryogenic service
1 Scope

This International Standard specifies the minimum requirements for the design, manufacture and

testing of pumps for cryogenic service.

This International Standard is applicable to centrifugal pumps. However, it can be applied to other

types of cryogenic pumps (e.g. reciprocating pumps), where applicable.

This International Standard also gives guidance on the design of installations (see Annex A).

It does not specify requirements for operation or maintenance.
NOTE For cryogenic fluids, see ISO 21029-1, ISO 20421-1 and/or ISO 21009-1.
2 Normative 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.

ISO 5198, Centrifugal, mixed flow and axial pumps — Code for hydraulic performance tests — Precision grade

ISO 21010, Cryogenic vessels — Gas/materials compatibility

ISO 21028-1, Cryogenic vessels — Toughness requirements for materials at cryogenic temperature —

Part 1: Temperatures below –80 °C

ISO 21028-2, Cryogenic vessels —Toughness requirements for materials at cryogenic temperature —

Part 2: Temperatures between –80 °C and –20 °C
ISO 23208, Cryogenic vessels — Cleanliness for cryogenic service
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
nominal size

alphanumeric designation of size for components of a pipework system, which is used for reference

purposes

Note 1 to entry: It comprises the letters DN followed by a dimensionless whole number which is indirectly related

to the physical size, in millimetres, of the bore or outside diameter of the end connections.

Note 2 to entry: The number following the letters DN does not represent a measurable value and is not to be used

for calculation purposes except where specified in the relevant standard.

Note 3 to entry: In those standards which use the DN designation system, any relationship between DN and

component dimensions is given, e.g. DN/OD or DN/ID.
[SOURCE: ISO 6708:1995, 2.1, modified]
© ISO 2016 – All rights reserved 1
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SIST EN ISO 24490:2017
ISO 24490:2016(E)
3.2
nominal pressure

alphanumeric designation used for reference purposes related to a combination of mechanical and

dimensional characteristics of a component of a pipework system

Note 1 to entry: It comprises the letters PN followed by a dimensionless number equal to at least the maximum

allowable pressure in bar.
Note 2 to entry: For a pump, PN can be different for inlet and outlet.

Note 3 to entry: For Europe, PN equals the design pressure (PS) as defined in the Pressure Equipment Directive

(2014/68/EU).
3.3
specified minimum temperature
lowest temperature for which the pump is specified
3.4
duty point
performance point defined by pressure or head and volume or mass flow rate
3.5
net positive suction head
NPSH

inlet total head increased by the head (in flowing liquid) corresponding to the atmospheric pressure

at the test location and decreased by the sum of the head corresponding to the vapour pressure of the

pump liquid at the inlet temperature and the inlet impeller height
Note 1 to entry: See also ISO 5198:1987, Table 1.
4 Requirements for pumps
4.1 General

Cryogenic centrifugal pumps shall comply with appropriate general standards. The appropriate general

standard(s) shall be subject to the particular circumstances and applicable regulations and should be

agreed between the manufacturer and the purchaser.

NOTE Commonly used standards are, e.g. ISO 5199, ISO 13709 (ANSI/API 610) or EN 809.

In the event of conflict, the requirements of this International Standard shall take precedence over the

general standards.
4.2 Materials
4.2.1 General

Materials of construction shall be selected taking into consideration that cryogenic pumps operate at

low temperature, often in a damp environment, and at times with liquid oxygen or flammable fluids.

The minimum requirements given in 4.2.2, 4.2.3 and 4.2.4 shall apply.
4.2.2 Mechanical properties at low temperature

Metallic materials which are under stress at low temperature and which exhibit a ductile/brittle

transition (such as ferritic steels) shall have minimum toughness values in accordance with ISO 21028-1

or ISO 21028-2 as appropriate.
2 © ISO 2016 – All rights reserved
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SIST EN ISO 24490:2017
ISO 24490:2016(E)

Metallic materials which can be shown to have no ductile/brittle transition do not require impact

testing.

Non-metallic materials are generally used only for seals or heat barriers. If such materials are to be

used for structural parts, the stress levels and material impact values shall be shown to be acceptable

for the intended use.
4.2.3 Corrosion resistance

Materials should be resistant to, or protected from, atmospheric corrosion. Where this is not achievable,

a suitable corrosion allowance shall be considered.
4.2.4 Oxygen and oxidizing fluids compatibility

If the specified minimum service temperature is equal to or less than the boiling point of air or the

pump is intended for oxygen service, the materials which are, or are likely to come, in contact with

oxygen or oxygen-enriched air shall be oxygen-compatible in accordance with ISO 21010.

If the pump is employed for oxidizing cryogenic fluids, e.g. nitrous oxide, the requirements for oxygen

compatibility should be taken into consideration.

In the case of nitrous oxide, the risk of decomposition shall also be considered.

Materials should be selected that minimize the potential for ignition and inhibit sustained combustion.

Suitable material properties are
— high ignition temperature,
— high thermal conductivity, and
— low heat of combustion.

Table B.1 lists materials found through testing and operating experience to be particularly suitable for

centrifugal cryogenic pumps in oxygen service. Materials other than those identified in Table B.1 may be

used but their selection shall be justified by specific testing or long-term experience in this application.

For (any) parts of the pump which are, or are likely to come, in contact with oxygen and which could be

exposed to energy sources such as friction, aluminium or aluminium alloy including aluminium bronzes

containing more than 2,5 % aluminium shall not be used. The use of aluminium or aluminium alloy for

any other parts shall only be adopted after careful consideration.

Stainless steel shall not be used for exposed thin components. Exceptions allowed are seal bellows,

trapped shims or gaskets and screw-locking devices of stationary parts where knowledge of past

satisfactory performance is available. However, suitable alternative materials, e.g. nickel or nickel alloy,

® ®1)
Monel and Inconel , should be considered.

NOTE Tin bronze has been found to be most suitable for the main “wetted” pump components. The most

common aluminium bronzes, which typically contain between 6 % and 11 % aluminium, have relatively high

heats of combustion and, if combustion occurs, are practically impossible to extinguish in an oxygen environment.

® ®

1) Monel and Inconel are the trademarks of products supplied by Special Metals Corporation, New Hartford,

New York, U.S.A. This information is given for the convenience of users of this International Standard and does not

constitute an endorsement by ISO of the product named. Equivalent products may be used if they can be shown to

lead to the same results.
© ISO 2016 – All rights reserved 3
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SIST EN ISO 24490:2017
ISO 24490:2016(E)
4.2.5 Hydrogen compatibility

Consideration should be given to the risk of hydrogen embrittlement when selecting materials and

determining stress levels for pumps for liquid hydrogen service; see ISO 21010 and ISO 11114-1,

ISO 11114-2, or ISO 11114-4 for guidance.

NOTE Thermal cycling of austenitic stainless steels in the presence of hydrogen might lead to accelerated

cracking.
4.3 Design
4.3.1 Pressure-containing parts

The high-pressure side of the pump shall be designed to withstand at least the nominal outlet pressure.

The low-pressure side of the pump shall be designed to withstand at least the maximum inlet

pressure +2 bar.

The material stress level from pressure might not be the dominant factor in pump design. The allowable

stress level may be calculated at the pressure rating, using ISO 21009-1 for guidance.

4.3.2 Performance

The pump design and installation shall meet the performance requirements specified on the data sheet

(or similar document). Examples of a data sheet can be found in ISO 5199 and ISO 9908.

4.3.3 Clearances

Clearances between moving and stationary parts within the pump shall be as large as practical,

consistent with good hydraulic performance and sealing. Material selection for components should

take into account the often large differences in expansion coefficients to ensure satisfactory clearances

and interferences at the operating temperatures and during cool-down.
4.3.4 Prevention of rubbing

The consequences of bearing failure or the consumption of parts by wear shall be considered,

particularly in pumps designed for liquid oxygen duty.
4.3.5 Fastenings

All internal fasteners shall be secured to prevent them loosening in service (e.g. friction nuts, tab

washers).

Consideration shall be given to more adequately securing items which might normally be held in place

by an interference fit only (e.g. wear rings). These components can cool down more quickly than others

and become temporarily loose.
4.3.6 Warm bearings

Rolling-element bearings designed to run warm shall be located or protected such that freezing of the

lubricating grease or oil is avoided. The effect of ice build-up over a period shall be considered. This can

result in overcooling of the bearing and can allow shaft-seal leakage to be forced directly into the driver

bearing. Motor-bearing heaters may be considered for cold standby pumps.
4.3.7 Cold bearings

For bearings designed to run cold, lubricated by the cryogenic fluid, the use of materials and design

arrangements that can safely withstand short-term dry running shall be considered.

4 © ISO 2016 – All rights reserved
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SIST EN ISO 24490:2017
ISO 24490:2016(E)
4.3.8 Bearing lubrication

For direct-coupled cryogenic pumps, grease and oils shall be suitable for all oxidizing and predictable

offset conditions. The lubricants should typically be suitable down to −40 °C.

Sealed bearings are preferred. Where bearing re-greasing in situ is required, grease drain plugs should

be provided to reduce the risk of accumulations of grease within the motor housing.

Liquid oxygen pumps shall be constructed so that possible oxygen leakage cannot contact any

hydrocarbon lubricant. If this cannot be prevented with certainty, the use of oxygen-compatible

lubricants meeting the requirement of ISO 21010 shall be considered. It should be noted, however, that

such oxygen-compatible lubricants are less able to protect the bearing against corrosion, generally

reduce the ability of the bearing to withstand load and speed, and may have some adverse reaction

with some material combinations.
4.3.9 Shaft seals

Shaft seals are usually either mechanical rubbing face or labyrinth type. Both have a high possibility of

leakage.

The design of the mechanical seal shall prevent metal-to-metal rubbing between the seal carrier and

the rotating seal ring when the soft face material wears out.

For pumps in oxygen service, there shall be no contact between the bellows and the shaft. This can, e.g.

be achieved by a protective sleeve between the bellows and the shaft.

Labyrinth shaft seals shall be treated as systems, engineered for the particular application. For pumps

in oxygen service, injected gas may be an inert gas or oxygen.
Leakage-detection devices should be considered, e.g. a low-temperature trip.

A slinger or other deflection device shall be used to prevent direct impingement of shaft seal leakage on

the driver bearing.
4.3.10 Purging
A tapping for a dry inert gas purge may be used to

— prevent the ingress of moisture (and possibly ice build-up) within the seal area,

— prevent the ingress of moisture into areas using lubricants (oxygen-compatible when required; see

4.2.4), and

— provide a barrier between oxygen-compatible and oxygen-non-compatible parts of a pump (e.g. cold

end and mechanical drive).
4.3.11 Prevention of particle contamination

Appropriate devices such as filters shall be used if there is a risk of particle contamination in service.

NOTE For recommended service conditions of filters, see A.1.10.
4.3.12 Specific requirement for flammable liquids

The rate of leakage from the pump and its accessories at any spot shall not exceed 1 mm /s, corrected

5 −3

to normal temperature and pressure [0 °C, 1013,25 mbar, (1,01325 × 10 Pa)] or 10 mbar l/s, and

its design should prevent the possibility of dangerous fluid accumulations. Methods for leak testing

can, e.g. be found in EN 1779. The leakage from any higher flow rates (from seal areas, etc.) shall be

col
...

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