1、BRITISH STANDARD BS EN ISO 1973:1996 Textile fibres Determination of linear density Gravimetric method and vibroscope method The European Standard EN ISO 1973:1995 has the status of a British Standard ICS 59.060BSENISO1973:1996 This British Standard, having been prepared under the directionof the Se
2、ctor Board forMaterials and Chemicals, waspublished under the authorityof the Standards Boardand comes into effect on 15 May 1996 BSI 11-1999 The following BSI references relate to the work on this standard: Committee reference TCI/24 Draft for comment 93/307688 DC ISBN 0 580 25725 8 Committees resp
3、onsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee TCI/24, Physical testing of textiles, upon which the following bodies were represented: Association of Consulting Scientists Association of Suppliers to the British Clothing Industry Briti
4、sh Apparel and Textile Confederation British Measurement and Testing Association British Polyolefin Textiles Association British Textile Machinery Association British Textile Technology Group British Throwsters Association Furniture Industry Research Association International Wool Secretariat Minist
5、ry of Defence SATRA Footwear Technology Centre Society of Dyers and Colourists Textile Finishers Association Textile Association Amendments issued since publication Amd. No. Date CommentsBSENISO1973:1996 BSI 11-1999 i Contents Page Committees responsible Inside front cover National foreword ii Forew
6、ord 2 1 Scope 3 2 Normative references 3 3 Definitions 3 4 Principle 3 5 Apparatus 3 6 Conditioning and testing atmospheres 4 7 Sampling 4 8 Procedure 4 9 Expression of results 5 10 Test report 5 Annex A (informative) Examples of calculation of mean linear density 6 Annex B (informative) Bibliograph
7、y 7 Annex ZA (normative) Normative references to international publicationswiththeir relevant European publications 8 List of references Inside back coverBSENISO1973:1996 ii BSI 11-1999 National foreword This British Standard has been prepared by Technical Committee TCI/24 and is the English languag
8、e version of EN ISO 1973:1995 Textile fibres Determination of linear density Gravimetric method and vibroscope method, published by the European Committee for Standardization (CEN). It is identical with ISO 1973:1995 published by the International Organization for Standardization (ISO). This British
9、 Standard supersedes BS 2016:1973 which is withdrawn. 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
10、obligations. Cross-references Publication referred to Corresponding British Standard ISO 139:1973 BS EN 20139:1992 Textiles Standard atmospheres for conditioning and testing ISO 1130:1975 BS 2545:1965 Methods of fibre sampling for testing ISO 6989:1981 BS 6176:1981 Method for determination of length
11、 and length distribution of staple fibres by measurement of single fibres Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theEN ISO title page, pages2 to8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may
12、have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 1973 November 1995 ICS 59.060 Descriptors: Textiles, fibres, tests, density measurement, determination, linear density, gravimetric analy
13、sis English version Textile fibres Determination of linear density Gravimetric method and vibroscope method (ISO 1973:1995) Fibres textiles Determination de la masse linique Mthode gravimtrique et mthode au vibroscope (ISO 1973:1995) Textilien-Fasern Bestimmung der Feinheit Gravimetrisches Verfahren
14、 und Schwingungsverfahren (ISO 1973:1995) This European Standard was approved by CEN on 1995-10-06. 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-
15、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 official versions (English, French, German). A version in any other language made by translation unde
16、r 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, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherla
17、nds, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1995 All rights or reproduction and communication in any form and by
18、 any means reserved in all countries to CEN and its members. Ref. No. EN ISO 1973:1995 EENISO1973:1995 2 BSI 11-1999 Foreword The text of the International Standard ISO 1973:1995 has been prepared by Technical Committee ISO/TC 38, Textiles, in collaboration with CEN/TC 248, Textiles and textile prod
19、ucts. 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 May 1996, and conflicting national standards shall be withdrawn at the latest by May 1996. According to the CEN/CENELEC Internal Regulations,
20、the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.ENISO1973:1995 BSI 11-1999 3 1 Scope This Internat
21、ional Standard specifies a gravimetric method and a vibroscope method for the determination of the linear density of textile fibres applicable respectively to: a) bundles of fibres; b) individual fibres. Useful data can be obtained on man-made fibres and, with less precision, on natural fibres. The
22、procedures can be applied only to fibres which can be kept straight and, in the case of bundles, parallel, during test preparation. These methods are properly applicable when the fibres are readily freed of crimp. They are not applicable to tapered fibres. NOTE 1The vibroscope method may not be appl
23、icable to hollow and flat (ribbon-like) fibres. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. Allstandards are subject to re
24、vision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 139:1973, Textiles Sta
25、ndard atmospheres for conditioning and testing. ISO 1130:1975, Textile fibres Some methods of sampling for testing. ISO 6989:1981, Textile fibres Determination of length and length distribution of staple fibres (bymeasurement of single fibres). 3 Definitions For the purposes of this International St
26、andard, the following definitions apply. 3.1 tension force tending to cause the extension of a body NOTE 2In textile testing, the tension applied is based on the linear density or cross-sectional area. 3.2 tensioning force force effective on a fibre specimen during the vibroscope test 4 Principle Tw
27、o methods for determining linear density are described: 4.1 Gravimetric method (direct method by weighing), for bundles of fibres Specimens of a given length are weighed on a balance. This method is applicable, to bundles of fibres. 4.2 Vibroscope method, for individual fibres Individual fibres of a
28、 given length and under specified tension are subjected to vibration at resonance frequency. The linear density is determined from the conditions of the resonance state, i.e. the resonance frequency, the length of the fibre and the tensioning force. The linear density is read directly on the scale o
29、f the vibroscope apparatus. This method assumes that the linear density of the tested length of the fibre is constant. NOTE 3For high-modulus fibres (e.g. aramid fibres) the use of the vibroscope method should be agreed on by the interested parties, because the high stiffness of such fibres may infl
30、uence the results. 5 Apparatus 5.1 Gravimetric method 5.1.1 Balance, suitable for weighing the bundles of fibres to an accuracy of at least 1 %. 5.1.2 Device for cutting the bundles under tension to a length known within an accuracy of 1 % and allowing an adjustment of the tension of the bundles to
31、be cut. For example, two razor blades set parallel in a suitable holder may be used. 5.1.3 Combsorter, for preliminary alignment of fibres. 5.1.4 Textile support fabric, of a colour contrasting with that of the fibres to be tested. 5.1.5 Glass plate, measuring approximately100mm 200 mm, with one pol
32、ished edge. 5.1.6 Forceps 5.2 Vibroscope method 5.2.1 Vibroscope 1) , having the following accuracy: a) The applied tensioning force shall be within the range of 0,5 % of the specified value; b) The error in the vibroscope reading of resonance frequency measured or applied shall not exceed 0,5 %. c)
33、 The error in the vibroscope reading of vibration length of the fibre shall not exceed 1 %. 1) For a list of suppliers of suitable vibroscope equipment, apply to the Secretariat of ISO Technical Committee 38.ENISO1973:1995 4 BSI 11-1999 6 Conditioning and testing atmospheres The atmospheres for prec
34、onditioning, conditioning and testing shall be in accordance with ISO 139. 7 Sampling To ensure that the laboratory sample is representative of the material and that the test specimen taken from the laboratory sample is representative of that sample, sampling shall be carried out in accordance with
35、ISO 1130. 8 Procedure 8.1 Gravimetric method 8.1.1 Condition the test specimens and carry out the tests in the standard atmosphere for testing as specified in clause 6. 8.1.2 From the laboratory test sample, take ten tufts having a mass of several milligrams and bring the fibres of each tuft into pa
36、rallel alignment by carefully combing them several times with the combsorter (5.1.3). 8.1.3 Cut the middle part of each combed tuft to a given length (as great as possible), under the minimum tension necessary to remove crimp, by means of the cutting device (5.1.2). Take the necessary precautions so
37、 that there are no free fibre ends anywhere except at the two ends of the cut bundle. 8.1.4 Place the ten bundles so obtained on the textile support fabric (5.1.4) and cover them with the glass plate (5.1.5), from the polished edge of which they shall protrude slightly. 8.1.5 From each of the ten bu
38、ndles in turn, take out five fibres so as to form a bundle of 50 fibres, in each case drawing the fibres from one cut end. Make at least ten of these bundles. Recondition the specimen in the atmosphere specified in clause 6, if necessary. Weigh these bundles individually, using the balance(5.1.1), t
39、o an accuracy of 1 %. NOTE 4If the bundle of 50 fibres cannot be weighed on the balance to the required 1 % accuracy, the number of fibres may be increased up to 500. 8.2 Vibroscope method 8.2.1 Check the vibroscope, before examining the laboratory test sample, as follows. Test 100 individual fibres
40、 using the vibroscope in question. Test these same fibres, for comparison, using the gravimetric method. Calculate the arithmetic mean and coefficient of variation of the vibroscope readings of linear density. If the coefficient of variation of the vibroscope readings is larger than 10 %, the sample
41、 is not suitable for determination of linear density using this vibroscope. Weigh the bundle of 100 fibres that have been tested with the vibroscope using the balance (5.1.1). Measure the length of all fibres in accordance with ISO 6989 with an accuracy of 1 %. Or, where appropriate, cut the 100 fib
42、res to a known length using the cutting device (5.1.2). Calculate the mean linear density, , of the fibre, expressed in decitex, using the following formula: Compare this mean linear density with the mean value of the linear density readout on the vibroscope. The relative difference shall not exceed
43、 3 % of the mean value of the vibroscope readings. 8.2.2 From the laboratory test sample, take ten tufts having a mass of several milligrams and with these form a bundle by repeated halving and doubling. From this bundle take a tuft of at least 50 fibres and condition them as specified in clause 6.
44、8.2.3 Fix each of the fibres to the vibroscope under the applied tensioning force, which shall be sufficient to remove the crimp, using forceps (5.1.6) and taking care to avoid any damage or distortion of the fibre. Calculate the tensioning force to be applied from the nominal linear density. If the
45、 nominal linear density is not known, an approximate value of the linear density shall be established by preliminary tests, recorded from the scale of linear density readings. Once this tensioning force has been selected, it shall be applied and maintained with the required accuracy (see 5.2.1). Nor
46、mally tensions chosen within the range (0,6 0,06) cN/tex are suitable. For highly crimped fibres, increase the tension to remove the crimp but not to stretch the fibre, in accordance with the vibroscope manufacturers specifications. Alterations in tensioning force shall be stated in the test report.
47、 where m b is the mass, in milligrams, of the fibre bundle; l i is the length, in millimetres, of the ith fibre in the bundle. l,bENISO1973:1995 BSI 11-1999 5 9 Expression of results Examples of calculations of mean linear density are given in Annex A. 9.1 Gravimetric method 9.1.1 For each bundle, c
48、alculate the mean linear density () of the fibre, and calculate the mean linear density (), expressed in decitex, of the fibre in all bundles tested, to three significant figures. 9.1.2 Calculate the coefficient of variation of the mean linear density (), expressed as a percentage to the nearest 0,1
49、 %. 9.1.3 Calculate the 95 % confidence interval of the mean linear density (), expressed in decitex, to the same precision as the mean linear density value. 9.1.4 Calculate the 95 % confidence interval expressed as a percentage of the mean lineardensity value (). If the value of the confidence interval expressed as a percentage of the mean is within 2 %, the number of bundles tested is adequate and the mean of the linear density shall be taken as the mean linear density of the laboratory sample. If the value of the c
