1、BRITISH STANDARD O Methods of test for petroleum and its products - BS 2000-477: Liquefied petroleum gases - Method of sampling- (Identical with IP 477-2001) The European Standard EN IS0 4257:2001 has the status of a British Standard ICs 75.160.30 BS EN IS0 4257:2001 BS 2000-477:2001 NO COPYING WITH
2、OUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BS EN IS0 4257:2001 National foreword This British Standard is the official English language version of EN IS0 4257:2001. It supersedes BS EN IS0 4257:1995 which is withdrawn. The UK participation in its preparation was entrusted to Technical C
3、ommittee PTU13, Petroleum testing and terminology, which has the responsibility to: - - aid enquirers to understand the text; present to the responsible international European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related
4、international and European developments and promulgate them in the UK. - A list of organizations represented on this committee can be obtained on request to its secretary. The Institute of Petroleum publishes and sells all Parts of BS 2000, and all BS EN petroleum test methods that would be Part of
5、BS 2000, both in its annual publication “Standard methods for analysis and testing of petroleum and related products and British Standard 2000 Parts” and individually. Further information is available from: The Institute of Petroleum, 61 New Cavendish Street, London W1M 8AR. Tel: 020 7467 7100. Fax:
6、 020 7255 1472. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI
7、 Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. This Bri
8、tish Standard, having been prepared under the direction of the Sector Committee for Materials and Chemicals, was published under the authority of the Standards Committee and comes into effect on 15 September 2001 6 Institute of Petroleum and BSI 08-2001 ISBN O 580 38158 7 Summary of pages This docum
9、ent comprises a front cover, an inside front cover, the EN IS0 title page, the EN IS0 foreword page, the IS0 title page, pages ii to iv, pages 1 to 7 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication I
10、 I I I 1 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM a EN IS0 4257 July 2001 ICs 75.160.30 Supersedes EN IS0 4257:1995 English version Liquefied petroleum gases - Method of sampling (IS0 4257:2001) Gaz de ptrole liqufies - Mthode dchantillonnage (IS0 4257:2001) This European Standard was appro
11、ved by CEN on 29 June 2001. 0 CEN members are bound to comply with the CENICENELEC 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
12、standards may be obtained on application to the 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
13、to the Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netheriands, Norway, Portugal, Spain, Sweden, Switzerland and Unit
14、ed Kingdom. EUROPEAN COMMlTEE FOR STANDARDIZATION EUROPISCHES KOMITEE FR NORMUNG COMITE EUROPEEN DE NORMALISATION Management Centre: rue de Stassart, 36 B-1050 Brussels a O 2001 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN IS0 4
15、257:2001 E EN IS0 4257:2001 Foreword The text of the International Standard IS0 4257:2001 has been prepared by Technical Committee ISO/TC 28 “Petroleum products and lubricants“ in collaboration with Technical Committee CEN/TC 19 “Petroleum products, lubricants and related products“, the secretariat
16、of which is held by NEN. This European Standard supersedes EN IS0 4257:1995. 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 January 2002, and conflicting national standards shall be withdrawn at
17、the latest by January 2002. According to the CENKENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembour
18、g, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. NOTE FROM CMC: The foreword is susceptible to be amended on reception of the German language version. The confirmed or amended foreword, and when appropriate, the normative annex ZA for the references to internation
19、al publications with their relevant European publications will be circulated with the German version. Endorsement notice The text of the International Standard IS0 4257:2001 was approved by CEN as a European Standard without any modification. INTERNATIONAL STANDARD EN IS0 4257:2001 IS0 4257 Second e
20、dition 2001 -07-1 5 Liquefied petroleum gases - Method of sampling Gaz de ptrole liqufis - Mthode dchantillonnage Reference number IS0 4257:2001(E) EN IS0 4257:2001 I ii Contents 1 EN IS0 4257:2001 Page Foreword . v 1 Scope 1 2 Term and definition . 1 3 Principle 1 4 General considerations for obtai
21、ning a representative sample . 1 5 Safety precautions . 2 6 Apparatus . 3 7 Preparing the sample container . 4 08 Procedure . 4 Bibliography 7 iii EN IS0 4257:2001 Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bod
22、ies). The work of preparing International Standards is normally carried out through IS0 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
23、 non-governmental, in liaison with ISO, also take part in the work. IS0 collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISOAEC Directives, P
24、art 3. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of
25、 this International Standard may be the subject of patent rights. IS0 shall not be held responsible for identifying any or all such patent rights. International Standard IS0 4257 was prepared by Technical Committee ISOTTC 28, Petroleum products and lubricants, Subcommittee SC 3, Static petroleum mea
26、surement. This second edition cancels and replaces the first edition (IS0 4257:1988), of which it constitutes a technical revision. iv EN IS0 4257:2001 Liquefied petroleum gases - Method of sampling WARNING - The use of this International Standard may involve hazardous materials, operations and equi
27、pment. This International Standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health and environment protection practices and determine the applicability of regulatory limitati
28、ons prior to use. 1 Scope This International Standard specifies the procedure to be used for obtaining samples of unrefrigerated liquefied petroleum gases (LPG). It is suitable for sampling from bulk containers, to provide samples for laboratory testing of products covered by IS0 91 62. This Interna
29、tional Standard is applicable for the provision of samples for compositional analysis by IS0 7941. It is not applicable for the provision of samples for trace analysis of low-boiling components. If trace analysis of low- boiling components is required, a variable-volume receiver such as that describ
30、ed in ASTM D 3700 should be used. 0 2 Term and definition For the purposes of this International Standard, the following term and definition applies. 2.1 liquefied petroleum gases LPG petroleum gases that can be stored and/or handled in the liquid phase under moderate conditions of pressure and at a
31、mbient temperature NOTE These gases consist predominantly of propane, propene, butanes and butenes, with small proportions of ethane, ethene and/or pentanes and pentenes. They are normally described in terms of the predominant hydrocarbon, e.g. commercial butane or commercial propane. 3 Principle A
32、liquid sample is transferred from the source into a sample container through a transfer line by purging the container and filling it with liquid, then providing a liquid ullage so that 80 % (V/V) of the container volume remains filled with liquid. NOTE For the purposes of this International Standard
33、, the term “% (V/V). is used to represent the volume fraction. 4 General considerations for obtaining a representative sample Great care is required to obtain a representative sample, especially if the material to be sampled is a mixture of liquefied gases. The following factors shall be taken into
34、account. a) Take samples from the liquid phase only. b) Avoid sampling from the bottom of a vessel. 1 EN IS0 4257:2001 The contents of tanks can be non-homogeneous. Homogeneity can be improved by circulating the contents 0 prior to sampling. A waiting period of 30 min is recommended after circulatio
35、n before sampling to permit settling of any aqueous material and to allow dissipation of any static charge that may have developed. When sampling from pipelines under flow conditions, the pressure in the line needs to be above vapour pressure to avoid two-phase conditions. Safety precautions 5.1 Gen
36、eral Because of the hazards involved, liquefied gases shall be sampled only by, or under the supervision of, persons familiar with the necessary safety precautions. Three areas of safety shall be considered: a) safety at the sampling point; b) safety of the container; c) safety during transport. 5.2
37、 Safety at the sampling point Care shall be taken to avoid contact by liquid LPG with the skin. Protective gloves and goggles shall be worn, and care shall be taken to avoid breathing vapours. Discharge of LPG can give rise to static electricity. Equipment shall be electrically grounded or bonded to
38、 the LPG tank before commencing and throughout the sampling operations. During purging and ullaging, safe means for disposal of waste vapours and liquids shall be provided. Compliance with local safety requirements and environmental regulations is necessary. 5.3 Safety of the container Sample contai
39、ners for use under pressure shall have been pressure-tested and shall be in accordance with national or local regulations, and the maximum safe operating pressure shall be marked on the container. Sampling operators shall ensure that the pressure rating of the container is suitable for use with the
40、product to be sampled and the conditions under which it is to be handled. Containers shall have been checked for gas tightness. Containers shall not be overfilled. There shall always be sufficient ullage space to allow liquid expansion under all storage and transport conditions. Carefully follow the
41、 procedure in clause 8, especially 8.4. Before use, check that the valves and pressure cylinder are not damaged. It is recommended that a frame collar, preferably square-shaped, be fitted around each valve to protect it from accidental damage during use, transport and storage. Containers shall be pl
42、aced in a cool location, shaded from direct sunshine, as soon as possible after taking the sample. Keep the sample cool until testing is completed or provide a means of avoiding excessive variation in its temperat u re. 5.4 Safety during transport Precautions shall be taken to protect the integrity
43、of the container by packing the container in a crate in accordance with regulatory requirements and by using a protective cap on the valves so that accidental unseating of the valves or tampering with them is prevented. It is recommended that valves should always be capped. 2 1 EN IS0 4257:2001 6 Ap
44、paratus 6.1 Sample container Use metal sampling containers and fittings of a type that ensure maximum safety and are corrosion-resistant to the product being sampled. A suitable material is stainless steel; an aluminium sample container shall not be used. The size of the container depends upon the a
45、mount of sample required for the laboratory tests that are to be made. If the container is to be transported, it shall conform to national or international regulations for the transportation of hazardous materials. The sampling container shall be of the two-valve type with an ullage tube as shown in
46、 Figure 1. The end of the container at which the ullage tube is fitted shall be clearly and indelibly marked. The length of the tube is such that the volume VI (see Figure 1) represents 20 % (VA) of the total capacity of the container. Total capacity = VI + V2, with V2 = 4 x Vi. Single-valve contain
47、ers shall not be used (see note 1 hereafter). Clearly label the cylinder with the following information: - cylinder number; - place at which the sample was taken; - ships name (if appropriate); - ships tank number (if appropriate); - shore tank number (if appropriate); - method of sampling; - date a
48、nd time of sampling; - description of the product; - initials or other identifying mark of the operator; - destination of the cylinder; - any further information relevant to the laboratory concerning the sample and the condition of the cylinder. NOTE 1 The single-valve containers present the followi
49、ng disadvantages: - without ullage tube, safety is not ensured; - with ullage tube, they cannot be purged and cleaned adequately with solvents. NOTE 2 The valves can be of the same type as those which fit commercially available LPG cylinders. 6.2 Sample transfer line Transfer lines shall be made of a material, preferably metal, that is impervious to the product to be sampled and capable of withstanding without leakage the pressure to which it is exposed in the procedure. They shall be equipped with two valves in addition to that at the product source and those on the contai
