1、October 2009DEUTSCHE NORM English price group 7No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 59.100.01!$Z4U“1551750w
2、ww.din.deDDIN EN ISO 1890Reinforcement yarns Determination of twist (ISO 1890:2009)English version of DIN EN ISO 1890:2009-10Verstrkungsgarne Bestimmung der Drehungszahl (ISO 1890:2009)Englische Fassung DIN EN ISO 1890:2009-10SupersedesDIN EN ISO 1890:1997-08www.beuth.deDocument comprises 10 pagesDI
3、N EN ISO 1890:2009-10 2 National foreword This standard has been prepared by Technical Committee ISO/TC 61 “Plastics” (Secretariat: ANSI, USA) in collaboration with Technical Committee CEN/TC 249 “Plastics” (Secretariat: NBN, Belgium). At present a DIN committee does not exist for this standard sinc
4、e the parties concerned have not shown any interest in work on the subject. The DIN Standards corresponding to the International Standards referred to in clause 2 of the EN ISO are as follows: ISO 2 DIN 60900-2 ISO 291 DIN EN ISO 291 ISO 1889 DIN EN ISO 1889 Amendments This standard differs from DIN
5、 EN ISO 1890:1997-08 as follows: a) The scope has been extended to include all reinforcement-fibre yarns. b) Normative references have been updated. c) The reference to ISO 1886 in Footnote 1 has been deleted as this standard has been withdrawn without replacement. d) The text of the standard has be
6、en editorially revised. Previous editions DIN EN ISO 1890: 1997-08 National Annex NA (informative) Bibliography DIN 60900-2, Yarns Terms for the designation of yarn construction in the Tex system DIN EN ISO 291, Plastics Standard atmospheres for conditioning and testing DIN EN ISO 1889, Reinforcemen
7、t yarns Determination of linear density EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 1890 June 2009 ICS 59.100.01 Supersedes EN ISO 1890:1997English Version Reinforcement yarns - Determination of twist (ISO 1890:2009) Fils de renfort - Dtermination de la torsion (ISO 1890:2009) Verstrkun
8、gsgarne - Bestimmung der Drehungszahl (ISO 1890:2009) This European Standard was approved by CEN on 30 May 2009. 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 al
9、teration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN 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 t
10、ranslation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Ge
11、rmany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMU
12、NG Management Centre: Avenue Marnix 17, B-1000 Brussels 2009 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 1890:2009: EContents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 5 Apparatus .5 6 Tes
13、t specimens6 7 Conditioning and test atmosphere 6 8 Procedure .6 8.1 Single yarns6 8.2 Folded or cabled yarns .7 9 Expression of results 7 10 Precision.7 11 Test report 8 2 DIN EN ISO 1890:2009-10 EN ISO 1890:2009 (E) 4 Principle5 Foreword This document (EN ISO 1890:2009) has been prepared by Techni
14、cal Committee ISO/TC 61 “Plastics” in collaboration with Technical Committee CEN/TC 249 “Plastics”, the secretariat of which is held by NBN. 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 Decembe
15、r 2009, and conflicting national standards shall be withdrawn at the latest by December 2009. 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
16、rights. This document supersedes EN ISO 1890:1997. 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, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
17、Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 1890:2009 has been approved by CEN as a EN ISO 1890:2009
18、without any modification. 3 EN ISO 1890:2009 (E) DIN EN ISO 1890:2009-10 1 Scope This International Standard specifies a method for the determination of twist in yarns made from textile glass, carbon, aramid or any other reinforcement fibres. The method applies to single yarns (one twist) and to fol
19、ded or cabled yarns (two or more twists). For folded and cabled yarns, the method is generally applied only to the final twist step. This International Standard is applicable to package-wound yarns. If the measurement is carried out on yarns taken from a beam (or warp) or from a fabric, the result i
20、s of an indicative nature only. The method is not applicable to products made from staple fibres. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest
21、 edition of the referenced document (including any amendments) applies. ISO 2:1973, Textiles Designation of the direction of twist in yarns and related products ISO 291, Plastics Standard atmospheres for conditioning and testing ISO 1889, Reinforcement yarns Determination of linear density 3 Terms a
22、nd definitions For the purposes of this document, the following terms and definitions apply. 3.1 Z twist S twist twist in a product if, when it is held in a vertical position, the spirals or helices formed by the fibres or filaments around its axis incline in the same direction as the central portio
23、n of the letter Z or S, respectively NOTE See ISO 2:1973, Clause 2. 4 DIN EN ISO 1890:2009-10 EN ISO 1890:2009 (E) 4 Principle The twist in a specimen of known length is removed by untwisting, i.e. by turning one of the ends of the specimen with regard to the other, until all the elements (yarns, fi
24、laments) constituting the specimen are parallel. The direction of twist in the yarn is noted and the value of the twist is expressed as the number of turns needed to eliminate the twist in 1 m of yarn. The determination of the twist must allow for the fact that the take-off system may have an influe
25、nce on the result. Thus when the yarn is taken off tangentially, the degree of twist inserted by the twist frame is not changed. On the other hand, if the yarn is taken off over-end, the measured twist is modified depending on the circumference of the bobbin. It will increase or decrease depending w
26、hether the yarn is taken off from alternate sides of the package. The method specified in this International Standard is based on the tangential take-off system. If required, the over-end twist can be either measured or an approximate value calculated using the following equation: over-end tangentia
27、l1TTD=where 1Dcorresponds to the twist induced by over-end take-off; D is the diameter, in metres, at the place on the bobbin where the specimen is taken. 5 Apparatus 5.1 Twist tester, i.e. an apparatus which has two clamps, one moving horizontally, the other rotating, mounted on a bar. The twist te
28、ster shall satisfy the following conditions: It shall be capable of measuring the number of turns to the nearest turn. The clamps shall grip the yarn without slipping and shall not damage the yarn. The tester shall include a device capable of measuring the length of the yarn between the clamps to an
29、 accuracy of 1 mm. It shall be possible to adjust the tension in the yarn between the clamps to a given value calculated as a function of the nominal linear density of the yarn. In practice, however, particularly for single yarns (and the final twist step in folded or cabled yarns), this tension doe
30、s not affect the result. For routine checks and also when the measurement of the elongation of the yarn resulting from untwisting is not required, this adjustment tension can be omitted, making sure, however, that the specimen is clamped so that it is just taut. The initial distance between the clam
31、ps shall be of 500 mm 1 mm. For carbon-fibre yarn with no twist or with a twist of less than 20 turns per metre, the yarn specification or the person ordering the determination may stipulate that a stand with a fixed clamp be incorporated to make it possible to test a specimen of length L given by 4
32、 m L 5 m. For the calculation of the twist, the actual length shall be measured to an accuracy of 0,05 m. 5 EN ISO 1890:2009 (E) DIN EN ISO 1890:2009-10 5.2 Dissection needle or thin blade. 5.3 Magnifying glass, for examination of the specimen, used to facilitate the separation of the yarn. 6 Test s
33、pecimens The determination is based on measurements carried out on three specimens taken consecutively from an elementary unit 1)or laboratory sample 2). The yarn specification or the person requesting the determination may stipulate that the determination be performed on a (specified) higher number
34、 of specimens which are generally taken from adjacent positions in the elementary unit or laboratory sample. Moreover, it may be stipulated that the determination be repeated at different places within the elementary unit or laboratory sample, either at given meterages or in the cylindrical part of
35、the package if it is not all of this shape. 7 Conditioning and test atmosphere No conditioning is required. However, in cases of dispute, the determination shall be carried out in a standard atmosphere as defined in ISO 291. 8 Procedure 8.1 Single yarns 8.1.1 If required, adjust the tension in the y
36、arn to 0,25 cN/tex 0,1 cN/tex. 8.1.2 If the linear density of the yarn is not known, determine it by the method specified in ISO 1889. 8.1.3 Ensure that the elementary unit or laboratory sample to be examined is free of external damage. If necessary, remove yarn from the elementary unit or laborator
37、y sample to obtain undamaged yarn. 8.1.4 Take off yarn tangentially (perpendicularly to the bobbin axis) and bring it directly, without cutting it, to the twist tester, fixing it first to the rotating clamp, then to the sliding clamp. Make sure that, during these clamping operations, the yarn is jus
38、t taut, first between the elementary unit or laboratory sample and rotating clamp, then between the two clamps. 8.1.5 Set the twist tester counter to zero. 8.1.6 Turn the rotating clamp in the direction which eliminates the twist until it becomes possible to insert a dissection needle or thin blade
39、between the filaments from the sliding clamp up to the rotating clamp. If necessary, use a magnifying glass to assist in inserting the needle and also to verify that all twist has been removed. 8.1.7 Record the number of turns on the counter and also the twist direction (Z or S, as per ISO 2). 8.1.8
40、 Repeat the measurement on the two other specimens. 1) The elementary unit is the smallest normally commercially available entity of a given product. 2) A laboratory sample is a part of the elementary unit from which the specimen(s) will be selected for the test. A laboratory sample is taken when it
41、 is impractical to bring the elementary unit into the test laboratory. 6 DIN EN ISO 1890:2009-10 EN ISO 1890:2009 (E) 8.2 Folded or cabled yarns The procedure described in 8.1 is also designed for the final twist step of folded and cabled yarns. If, after measuring the final twist step, the determin
42、ation is also to be performed on the previous twist steps, proceed as follows: Immediately after measurement of the final twist step: cut out all the yarns constituting the specimen except one; reset the counter to zero and make sure that the specimen is under slight tension so as to keep it straigh
43、t; determine the degree of twist, taking into account the actual length of the specimen; if necessary (for cabled yarns), repeat the operation on the previous twist step. 9 Expression of results Calculate, for each specimen, the twist T, in turns per metre, using the equation NTL= where N is the num
44、ber of turns necessary to untwist the specimen; L is the length, in metres, under standard tension prior to untwisting. Calculate, from the measurements made on the three specimens, the average of the twist, T , in turns per metre. Report this value as the result of the determination. If more than t
45、hree specimens were taken for the determination (see Clause 6), the results obtained for the various specimens in each determination shall be dealt with in accordance with the referring yarn specification or as specified by the person ordering the determination. 10 Precision The precision of this te
46、st method is not known because interlaboratory data are not available. 7 EN ISO 1890:2009 (E) DIN EN ISO 1890:2009-10 11 Test report The test report shall include the following information: a) a reference to this International Standard; b) all details necessary for identification of the yarn examine
47、d; c) the sampling procedure used and the length of the specimens, if not 0,5 m; d) the result of the determination (direction of twist and value of twist) and, if required, the results for each specimen; e) details of any operation not specified in this International Standard, as well as of any incident liable to have had an effect on the results; f) the date of the test. 8 EN ISO 1890:2009 (E) DIN EN ISO 1890:2009-10 DIN EN ISO 1890:2009-10 EN ISO 1890:2009 (E)
