BS ISO 123-2001 Rubber latex - Sampling《橡胶胶乳 取样》.pdf

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1、BRITISH STANDARD BS ISO 123:2001 Rubber latex Sampling ICS 83.040.10 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBS ISO 123:2001 This British Standard, having been prepared under the direction of the Sector Committee for Materials and Chemicals, was published under the auth

2、ority of the Standards Committee and comes into effect on15 August 2001 BSI 08-2001 ISBN 0 580 37976 0 National foreword This British Standard reproduces verbatim ISO 123:2001 and implements it as the UK national standard. It supersedes BS 6057-2:1987 which is withdrawn. The UK participation in its

3、preparation was entrusted to Technical Committee PRI/50, Natural and Synthetic Rubber, 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 publications

4、 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 Standards Electronic Catalogue A British Standard does not purport to include all the necessary provisions o

5、f 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. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the

6、 interpretation, or proposals for change, and keep the 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 ISO title page, pages ii to iv, pages 1 to 8, an ins

7、ide back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsINTERNATIONAL STANDARD ISO 123 Third edition 2001-05-15 Reference number ISO 123:2001(E) Rubber latex Sampling L

8、atex de caoutchouc chantillonnageii ISO 123:2001(E) iii Contents Page 1 Scope . 1 2 Normative references . 1 3 Terms and definitions 1 4 Principle 2 5 Apparatus . 2 6 Sampling . 3 7 Labelling the laboratory sample and the test sample . 7 8 Sampling report 8ISO 123:2001(E) iv Foreword ISO (the Intern

9、ational 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 com- mittees. Each member body interested in a subject for which a technical committee has

10、 been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liai- son with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical

11、 standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 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

12、at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. International Standard ISO 123 was p

13、repared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 3, Raw materials (including latex) for use in the rubber industry. This third edition cancels and replaces the second edition (ISO 123:1985), which has been technically revised. The principal differences lie in mor

14、e precise definitions and specifications for the frequency of sampling. In addition, the method of homogenizing and sampling latex in drums fitted with bungs has been modified to take account of practical considerations.INTERNATIONAL STANDARD ISO 123:2001(E) 1 Rubber latex Sampling WARNING Persons u

15、sing this International Standard should be familiar with normal laboratory practice. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure complian

16、ce with any national regulatory conditions. 1 Scope This International Standard specifies procedures for sampling natural rubber latex concentrate and for sampling syn- thetic rubber latices and artificial latices. It is also suitable for sampling rubber latex contained in drums, tank cars or tanks.

17、 The procedures may also be used for sampling plastics dispersions. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of

18、, any of these publica- tions do not apply. However, parties to agreements based on this International Standard are encouraged to investi- gate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative

19、 document referred to applies. Members of ISO and IEC maintain reg- isters of currently valid International Standards. ISO 124:1997, Latex, rubber Determination of total solids content. ISO 706:1985, Rubber latex Determination of coagulum content (sieve residue). ISO 3310-1:2000, Test sieves Technic

20、al requirements and testing Part 1: Test sieves of metal wire cloth. ISO 15528:2000, Paints, varnishes and raw materials for paints and varnishes Sampling. 3 Terms and definitions For the purposes of this International Standard, the following terms and definitions apply. 3.1 lot a definite quantity

21、of latex processed or produced under conditions which are presumed uniform NOTE A lot may be in one or more containers or vessels. For example, it may consist of several drums of latex. 3.2 sample a quantity of latex that has been drawn from a lot 3.3 laboratory sample a quantity of latex intended f

22、or laboratory inspection and testing and that is representative of the lotISO 123:2001(E) 2 3.4 test sample a quantity of latex suitable for testing, obtained by straining the laboratory sample NOTE The laboratory sample, not the test sample, is used for the determination of coagulum content (see 6.

23、5.5). 3.5 test portion a quantity of latex taken from the test sample (3.4) or laboratory sample (3.3), for the purpose of a single specific test, for example the amount actually weighed out from the test sample for a single determination of total solids content 3.6 coagulum content/sieve residue co

24、arse foreign matter and flocculated rubber retained under the conditions of the test (ISO 706) on a filter with aver- age aperture width of complying with ISO 3310-1 NOTE In the context of examination of latex shipments, bulk deliveries, etc., this is what is generally understood by “coagulum”. Piec

25、es of latex skin and coagulated rubber should not be included in the laboratory sample. 4P r i n c i p l e A representative laboratory sample is taken from the bulk of the latex. The test sample is prepared by straining the laboratory sample. 5 Apparatus No part of the equipment to be immersed in th

26、e latex shall contain copper. 5.1 Stirrer, for homogenization of latex in drums. For open-headed drums, use either 5.1.1 or 5.1.2. For drums fitted with a bung, see 6.4.1.4. 5.1.1 Plunger, consisting of a perforated, chrome-plated or stainless-steel disc of diameter approximately , with smooth-edged

27、 holes of diameter approximately . 5.1.2 Motor-driven stirrer, capable of operating at a speed of to ( to ). A suitable type of motor-driven stirrer consists of a stainless-steel propeller of minimum diameter, mounted on a stainless-steel shaft sufficiently long for the propeller to be at a distance

28、 of about one-tenth the depth of the latex from the bottom of the drum. If desired, two propellers may be used on the same shaft, in which case the lower one shall meet the foregoing re- quirements as regards position. The rotational frequency shall be such as to give a brisk turnover without creati

29、ng a vortex. 5.1.3 Motor-driven drum roller (optional, see 6.4.1.5), capable of rotating a drum at approximately () . 5.2 Sampling devices, suitable for the removal of an approximately representative sample from a known depth in the latex. Such devices shall be constructed of materials inert to late

30、x. 5.2.1 Sampling tubes for latex in drums Use either 5.2.1.1 or 5.2.1.2. 5.2.1.1 Sampling tube, of material inert to the latex, such as glass, stainless steel or inert plastic, having an inter- nal diameter of to and a length of at least , open at both ends and having a stopper for closing the uppe

31、r end while withdrawing it from the latex. 180 m 10 m 150 mm 10 mm 5 rad/s 21 rad/s 50 r/min 200 r/min 110 mm 1 rad/s 10 r/min 1dm 3 10 mm 15 mm 1 mISO 123:2001(E) 3 NOTE Inserting a tube open at both ends into the latex effectively provides a cross-section of the latex at all depths as a sample. 5.

32、2.1.2 Sampling tube, stainless steel, of internal diameter approximately and length at least , the bot- tom of which can be opened or closed by remote control. A drawing of a suitable device is given in Figure 1. 5.2.2 Sampling devices for latex in tank cars or tanks Use 5.2.2.1 if the depth of the

33、latex is or more. Use either 5.2.2.1 or 5.2.2.2 if the depth is less than . 5.2.2.1 Cylindrical stainless-steel vessel, of capacity approximately , closed by a lid or bung that can be opened by remote control. Such a vessel may be rigidly mounted for insertion to the required depth. A device similar

34、 to that shown in Figure 2 is suitable. A variety of other suitable devices for sampling are given in ISO 15528. 5.2.2.2 Sampling tube, stainless steel, of internal diameter , similar to 5.2.1.2 but length , the bottom of which can be opened or closed by remote control. 5.3 Beakers, of capacity , to

35、 receive the latex from the sampling tube or vessel. The beakers shall be shock- resistant and have a smooth inner surface that is chemically inert to latex. 5.4 Sample bottles, of capacity , with screw caps. The bottles shall have a smooth inner surface and be made of material that is chemically re

36、sistant to latex. Glass and some types of plastic are suitable materials. Thin flexible containers shall not be used. NOTE For purposes of trans-shipment, narrow-necked containers with a deep thread are preferable. 5.5 Filter, of stainless-steel wire or synthetic cloth inert to latex, with an averag

37、e aperture width of , complying with ISO 3310-1. 6 Sampling 6.1 General At all stages of sampling, avoid introducing air into the latex and keep exposure of the latex to air to a minimum. 6.2 Frequency of sampling 6.2.1 Unless otherwise agreed, sampling shall be carried out at the frequency specifie

38、d in 6.2.2 and 6.2.3. 6.2.2 Every lot shall be sampled. 6.2.3 Where a lot has been divided between a number of distinct containers (e.g. drums), samples shall be taken from of the containers with a minimum of one and rounded up to the nearest whole number (i.e. two from twelve, seven from sixty-four

39、, etc.). Select the containers from which the samples are to be withdrawn at random throughout the consignment. 6.3 Preliminary examination Examine the latex visually, and record the presence of creaming, gross coagulum, skin and foreign matter. 25 mm 1 m 3m 3m 1dm 3 25 mm 3m 2dm 3 1dm 3 180 m 10 m

40、10 %ISO 123:2001(E) 4 Key 1 Handle 2S p r i n g 3 Tube 4 Guides for valve rod 5S i m p l e v a l v e Figure 1 Sampling tube for drums, tank cars and smaller tanks (not to scale)ISO 123:2001(E) 5 Key 1 Handle (manual compression opens lid) 2 Rods 3L i d 4 Container of appropriate size a Suitable leng

41、th for taking sample Construction material: stainless steel Figure 2 Example of a latex-sampling deviceISO 123:2001(E) 6 6.4 Sampling from drums 6.4.1 Homogenization 6.4.1.1 Homogenize the latex manually as specified in 6.4.1.2 or mechanically as specified in 6.4.1.3 or, if appropri- ate, by means o

42、f a drum roller as specified in 6.4.1.5. 6.4.1.2 If the drum is of the open-head type, remove the end head and agitate the contents for at least , pref- erably by means of a perforated stainless-steel plunger (5.1.1). 6.4.1.3 Alternatively, agitate the contents of the drum by means of the motor-driv

43、en stirrer (5.1.2) for to ho- mogenize the latex. Avoid excessive stirring. 6.4.1.4 If the drum is of the closed-head type fitted with a bung and contains less than air space, then manual or mechanical homogenization is impractical. Lay the drum on its side and roll it to and fro briskly for not les

44、s than . Turn the drum so that it is standing on the end which was formerly uppermost and allow to stand for about , then repeat the rolling operation for a further . 6.4.1.5 Alternatively, if a single drum is to be sampled it is permissible to homogenize the latex by rolling the drum on a drum roll

45、er for at about ( ). 6.4.2 Taking the laboratory sample (see 3.3) 6.4.2.1 General After the latex has been homogenized (see 6.4.1), take the sample without delay as specified in 6.4.2.2 or 6.4.2.3, using a clean, dry sampling tube (5.2.1). Take care to avoid the inclusion of any gross coagulum or sk

46、in with the sample. 6.4.2.2 Sampling from a single drum Insert the sampling tube (5.2.1), open at both ends, slowly into the drum until it reaches the bottom. Then close the upper end of the tube with the stopper, withdraw it and transfer the contents to a clean, dry sample bottle (5.4). Re- peat th

47、e operation until sufficient latex has been obtained to fill the sample bottle, leaving an air space of to of the volume (to allow for thermal expansion), and screw the cap firmly onto the bottle. NOTE It is important that the sample bottle is almost full and airtight. 6.4.2.3 Sampling from several

48、drums Where sampling of the same lot of latex from several drums is to be carried out, for example in sampling (see 6.2.3), and it has been agreed that the samples may be blended, the amount of latex withdrawn from each drum may be reduced proportionately. In this case, the individual samples shall

49、be combined in a beaker (5.3) and stirred briefly to ensure uniformity and the resultant laboratory samples bottled (multiple samples may be required, for example for arbitration). 6.5 Sampling from tank cars and tanks 6.5.1 General Samples are initially taken from different depths to ensure that the latex is homogeneous. NOTE For fixed tanks, establishing suitable conditions which result in homogeneity will make it unnecessary to check for homogeneity each time a sample is taken. 5 min 10 min 2% 10 min 15 min 10 min 24 h 1 rad/s 10 r/min 2% 5% 10 %ISO 12