1、BRITISH STANDARD BS EN 12300:1999 Incorporating Amendment No. 1 Cryogenic vessels Cleanliness for cryogenic service The European Standard EN 12300:1998, with the incorporation of Amendment A1:2006, has the status of a British Standard ICS 27.200 BS EN 12300:1999 This British Standard, having been pr
2、epared under the direction of the Engineering Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 February 1999 BSI 2006 ISBN 0 580 30386 1 National foreword This British Standard is the English language version of EN 12300:1998, including amend
3、ment A1:2006. 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 1:2006 is indicated by !“. The UK participation in its preparation
4、was entrusted to Technical Committee PVE/18, Cryogenic vessels, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred t
5、o in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions
6、of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or pr
7、oposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 7 and a back cover. The BSI copyright notice display
8、ed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments 16379 31 July 2006 See national forewordCEN European Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue
9、 de Stassart 36, B-1050 Brussels 1998 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. EUROPEAN STANDARD EN 12300 NORME EUROPE ENNE EUROPA ISCHE NORM November 1998 ICS 27.200 Descriptors: pressure vessels, cryogeny, area, cleanliness checks, cl
10、eaning, protection, specifications, marking English version Cryogenic vessels Cleanliness for cryogenic service Re cipients cryoge niques Proprete Kryo-Beha lter Reinheit fu r den tiefkalten Betrieb CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditi
11、ons 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 Central Secretariat or to any CEN member. This European Standard exists in three of
12、ficial versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria
13、, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. + A1 May 2006 This European Standard was approved by CEN on 1 September 1998. Ref: No. EN 12300:1998 EPage 2 EN 123
14、00:1998 BSI 02-1999 Foreword This European Standard has been prepared by Technical Committee CEN/TC 268, Cryogenic vessels, 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
15、, at the latest by May 1999, and conflicting national standards shall be withdrawn at the latest by May 1999. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Repu
16、blic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Definitions 3 4 Requirements 3 5 Cleaning procedure 3 6 Cleanliness ev
17、aluation 3 7 Post cleaning protection 3 8 Marking 4 Annex A (informative) Inspection methods 5 ForewordtoamendmentA1 This document (EN 12300:1998/A1:2006) has been prepared by Technical Committee CEN/TC 268 “Cryogenic vessels”, the secretariat of which is held by AFNOR. This Amendment to the Europea
18、n Standard EN 12300:1998 shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2006, and conflicting national standards shall be withdrawn at the latest by November 2006. This document has been prepared under a manda
19、te given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard
20、: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. This document has
21、 been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association.Page 3 EN 12300:1998 BSI 02-1999 1 Scope This standard specifies the minimum requirements for the cleanliness of all surfaces of cryogenic vessels and associated accessories that are in con
22、tact with the cryogenic fluid at any expected operating conditions. This standard defines the acceptable level of surface and particle contamination to minimize the risk of malfunction of equipment and ensure safety against ignition when in contact with oxygen or oxidizing fluids (see EN 720-2). 2 N
23、ormative references EN 720-2, Transportable gas cylinders Gases and gas mixtures Part 2: Determination of flammability and oxidizing ability of gases and gas mixtures. prEN 1251-1:1995, Cryogenic vessels Transportable vacuum insulated vessels of not more than 1000 litres volume Part 1: Fundamental r
24、equirements. EN 1797-1, Cryogenic vessels Gas/material compatibility Part 1: Oxygen compatibility. 3 Definitions For the purpose of this European Standard, the following definitions apply. 3.1 cryogenic fluid see prEN 1251-1:1995 3.2 oxidizing fluid cryogenic fluid with oxidizing properties in accor
25、dance with EN 720-2 4 Requirements 4.1 General requirements Chips, foreign matter, major potentially loose particles such as oxide scale and weld spatter, are not acceptable. Particles visible under daylight or white light without magnification are not acceptable. More stringent requirements for par
26、ticle size may be required depending upon the design of the system to avoid malfunction of equipment. Free water shall not be detectable by visual examination. 4.2 Additional requirements for oxygen and oxidizing fluids For oxygen and other oxidizing fluids, hydrocarbon contamination, paint, adhesiv
27、es, sealants and protective coating shall not be detectable by visual examination using white light unless they are oxygen compatible in accordance with EN 1797-1. The maximum acceptable hydrocarbon contamination (oil, grease, etc.) is 500 mg/m 2 . 5 Cleaning procedure Any cleaning procedure may be
28、used, providing the requirements of 4.1 and 4.2, if relevant, are met. If solvent or cleaning agents are used, they shall be compatible with all materials to be cleaned in particular plastics. Special care shall be taken to remove any non oxygen compatible agents (see EN 1797-1) from equipment clean
29、ed for oxygen or oxidizing fluid service. 6 Cleanliness evaluation An inspection and sampling method shall be selected to ensure that the requirements of 4.1 and 4.2,i f relevant, are met. It shall take into account the cleaning procedure to be used, the equipment to be cleaned and its level of cont
30、amination. Cleanliness evaluation methods may include those listed in annex A. The method of inspection shall not itself result in contamination levels greater than those specified in 4.1 and 4.2. The cleanliness evaluation method shall be documented and the results obtained shall be recorded. 7 Pos
31、t cleaning protection After cleaning, items shall be protected to maintain their clean condition until used. To reduce the risk of condensing any atmospheric moisture during storage, consideration shall be given to purging and sealing the equipment. Any packaging, plugs, etc. that can contact the cl
32、ean surfaces shall be clean and removable without leaving any residue. Any packaging material shall be strong enough to resist the expected handling and storage conditions and be able to be sealed and water proof. Any protective gas used shall be dry and oil and dust free. Any pressurizing gas shall
33、 be kept at low pressure compatible with the strength of the packaging and should not exceed 0,5 bar. For pressure above 0,5 bar the package may fall under transportable pressure vessels regulation. The following referenced documents are indispensable for the application of this document. For dated
34、references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ! “Page 4 EN 12300:1998 BSI 02-1999 8 Marking Evidence of conformity with the requirements of this standard shall be documented by either: a certifica
35、te accompanying the equipment/item; or a label fixed to the protective packaging or equipment/item. The certificate or label shall indicate: “EN 12300 O 2 ” when cleaned for oxygen or other oxidizing fluids; “EN 12300” when cleaned for other cryogenic fluids only. If a protective gas is used, the ty
36、pe of gas and its pressure shall be legibly marked.Page 5 EN 12300:1998 BSI 02-1999 Annex A (informative) Inspection methods A.1 General Various methods exist for determining the cleanliness acceptance of equipment and it is necessary that the method selected complements the cleaning method used. Th
37、is annex covers the most practical and effective methods available. It is necessary that competent persons with the necessary training and relevant industrial experience are used for this activity. All parts being checked by solvent flushing or immersion should be able to drain freely to empty the s
38、olvent. If an area is identified which cannot freely drain, a method should be developed to remove completely the solvent without leaving contamination. For parts that are inaccessible for inspection after assembly, it may be necessary to disassemble or inspect parts prior to assembly. Consideration
39、 should be given to any contamination which may occur during the assembly of inspected components. If an inspection reveals the presence of any contaminants, the item should be partially or totally recleaned. Persistent rejection requires a re-evaluation of the cleaning methods and quality control p
40、rovisions before re-acceptance. A.2 Direct visual examination with daylight or white light This is the most common inspection method used to detect the presence of contaminants on equipment with easily accessible surfaces. This method will without magnification detect very small particulate matter a
41、nd moisture, oils, grease, etc. in relatively small amounts. The effectiveness of this method is dependent on the roughness of the inspected surface. The method can be used for sandblasted or mechanically cleaned steel surfaces. Magnifying glasses are not necessary, but it is important to have a suf
42、ficient bright level of daylight or artificial white light. Visual examination of the surfaces is appropriate for detecting: moisture (free water); cleaning agents; flux residues from brazing, soldering or welding; rust and loose scale, weld spatters, particles, fibres or other foreign matter; organ
43、ic material such as oils, grease, paint, etc This direct visual examination method enables detection of a hydrocarbon contamination level of 500 mg/m 2 . A.3 Direct visual examination method with ultraviolet light Ultraviolet light causes many common, but not all, hydrocarbon or organic oils to fluo
44、resce. An ultraviolet light with a wavelength of about 370 nm used in dark or near darkness at a distance of about 10 cm to 20 cm from the surface or piece being examined can show fluorescent areas for further inspection by other means such as wipe test, etc. Fluorescent traces due to material resid
45、ues known to be harmless are acceptable. When considering a piece of equipment cleaned for use in oxygen service, it is important not to rely alone on the result of this test as, for example, some vegetable oils do not fluoresce under ultraviolet light. Therefore although this test can be useful, it
46、 is certainly not the most important inspection method and should be supported by white light and/or wipe tests. NOTE Excessive exposure to direct or reflected ultraviolet light can cause eye and skin damage and therefore care should be taken when it is being used and the lamp manufacturers instruct
47、ions should be complied with. A.4 Wipe test method This test is useful when white light examination has been inconclusive. The surface is rubbed lightly with a clean lintfree cotton or linen cloth or with a white filter paper. This cloth or paper is examined under white light and/or ultraviolet ligh
48、t to find any contaminating traces. A light oxide discoloration is in some cases acceptable. Since it is not acceptable to leave paper or cloth particles on the equipment, this method is not recommended for rough or cast materials. A.5 Water break test This test may be used to detect oily residues n
49、ot found by other means. The surface is wetted with a spray of clean water. This should form a thin layer and remain unbroken for at least 5 s. Beading of the water droplets indicates the presence of oil contaminants. A.6 Solvent contamination test method This inspection method is used to check the result of highly specialized methods of solvent cleaning when inaccessible surfaces or bigger installations have to be cleaned.
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