1、UDC 677.074:677.017.3:620.168.2 DEUTSCHE NORM February 199# Determination of number of threads per unit Construction and methods of analysis (IS0 721 1-2 : 1984, modified) English version of DIN EN 1049-2 length of textile woven fabrics DIN - EN 1 049 Part 2 This standard incorporates the modified E
2、nglish version of IS0 721 1-2. Textilien; Gewebe; Konstruktion, Untersuchungsverfahren; Bestimmung der Anzahl der Fden je Lngeneinheit (IS0 721 1-2: 1984, modifiziert) Supersedes DIN 53853, January 1973 edition. European Standard EN 1049-2:1993 has the status of a DIN Standard. A comma is used as th
3、e decimal marker. National foreword This standard has been published in accordance with a decision taken by CEN/TC 248 to adopt International Standard IS0 721 1-2 as a European Standard. The responsible German body involved in the preparation of this standard was the Normenausschu Materialprfung (Ma
4、terials Testing Standards Committee). DIN EN 20 139 is the standard corresponding to International Standard IS0 139 referred to in clause 2. Standards referred to (and not included in Reference) DIN EN 20 139 Textiles; standard atmospheres for conditioning and testing Previous editions DIN DVM 3801
5、Part 4 = DIN 53801 Part 4: 01.37; DIN 53 853: O1 55, 01.73. Amendments DIN 53853, January 1973 edition, has been superseded by the specifications of DIN EN 1049-2, which is identical to IS0 721 1-2. International Patent Classification D 06 H 003/00 G O1 N 033/36 EN comprises 8 pages. Beuth Verlag Gm
6、bH, Berlin, has the exclusive right of sale for German Standards (DIN-Normen). DIN EN 1049 Pari 2 Engl. Price group 7 08.94 Sales No. 1107 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 1049-2 December 1993 UDC 677.074: 677.01 7.3: 620.1 68.2 Descriptors: Textiles, woven fabrics, testing, dete
7、rmination, number of threads, yarns. English version Textiles Construction - Methods of analysis Determination of number of threads per unit length (IS0 721 1-2 : 1984, modified) Woven fabrics Textiles: tissus: construction; mthodes danalyse: dtermination du nombre de fils par unit de longueur (IS0
8、721 1-2: 1984, modifie) Textilien; Gewebe; Konstruktion, Unter- suchungsverfahren; Bestimmung der Anzahl der Fden je Lngeneinheit (IS0 721 1-2: 1984, modifiziert) This European Standard was approved by CEN on 1993-12-16 and is identical to the IS0 Standard as referred to. CEN members are bound to co
9、mply with the CENKENELEC 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 standards may be obtained on application to the Central Se
10、cretariat 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 GEN member into its own language and notified to the Central Secretariat has the same status as the of
11、ficial versions. CEN members arethe national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de
12、 Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels O 1993. Copyright reserved to all CEN members. Ref. No. EN 1049-2:1993 E Page 2 EN 1049-2 : 1993 Foreword This European Standard has been taken over by CENiTC 248 Textiles and textile products from
13、 the work of TC 38 Textiles of the International Organization for Standardization (SO). It is based on IS0 721 1-2: 1984 Textiles; woven fabrics: COnStrUCtiOn; methods of analysis; determination of number of threads per unit length This European Standard shall be given the status of a national stand
14、ard, either by publication of an identical text or by endorsement, and conflicting national standards withdrawn, by June 1993 at the latest. In accordance with the CENICENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finl
15、and, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of the International Standard IS0 721 1-2: 1984 was approved by CEN as a European Standard with agreed common modifications as
16、given below.*) *) Translators note. All modifications have been incorporated in the text of the EN. Page 3 EN 1049-2 : 1993 1 Scope and field of application This part of IS0 7211 specifies three methods for the deter- mination of the number of threads per centimetre in woven fabrics. Any of the thre
17、e methods may be used, the choice depending on the character of the fabric. However, in case of dispute method A is recommended. Method A: Dissection of fabric, suitable for all fabrics. This is the most laborious method but has fewer limitations than the others; in particular, it is the only one th
18、at is really suitable for the examination of certain folded structures and other complicated weaves. Method 6: Counting glass, suitable for woven fabrics with more than 50 threads per centimetre. Method C: Traversing thread counter, suitable for all fabrics. Where the number of threads per centimetr
19、e is low, it may be convenient to express the results as the number of threads per decimetre. NOTE - Methods using parallel line gratings and tapered line gratings have been given in the annex for information. These methods have not been considered accurate enough to be used as standard test methods
20、 but can be used to give rough and ready estimates for routine testing. 2 Reference I SO 139, Textiles Standard atmospheres for conditioning and testing. 3 Principle Three methods of determining the number of threads per centimetre are specified, any of which may be used, the choice depending on the
21、 character of the fabric. The prin- ciples are as follows: Method A: A section of fabric of dimensions in accor- dance with those given in clause 4 is dissected and the number of threads counted. The threads that are to be counted are preferably short, 1 or 2 cm being suitable. Method 6: The number
22、of threads visible within the aperture of a specified counting glass is determined. Method C: The number of threads per centimetre of the fabric is determined with the aid of a traversing thread counter. 4 Minimum measuring distance Use the appropriate minimum measuring distance specified in the tab
23、le. Table - Minimum measuring distance Accuracy in (count to within cm 0.5 thread) Number Number Minimum distance of threads measuring of threads percentage per pei test Less than 10 10 to 25 50 to 125 1.0 to 0.4 25 to 40 75 to 120 0.7 to 0.4 More than 40 For the method A, take test pieces containin
24、g at least 100 threads. For narrow fabrics having a width of 10 cm or less, count all warp threads including the selvedge ends and express the result as threads per full width. When fabrics are patterned by broad areas of higher or lower density of thread spacing, select test specimens containing at
25、 least one weave repeat (see clause 10). 5 Conditioning and testing atmosphere The atmosphere for preconditioning, conditioning and testing shall be as specified in EN 20 139. 6 Test specimens No specially prepared specimens are required except for method A (see 7.21, but count the threads at not le
26、ss than five different points selected to represent the fabric as fully as poss- ible. Expose the fabric or specimens to the standard at- mosphere for testing for at least 16 h before making the test. Page 4 EN 1049-2 1993 7 Method A - Dissection of fabric 7.1 Apparatus 7.1.1 Clamp, holding two shor
27、t pins parallel and with their points being within I 0.02 cm of the minimum measuring distance specified in clause 4. Alternatively, when a clamp is not available, 7.1.2 Two dissecting needles and 7.1.3 Heavy steel rule. whole repeats in the measuring distance, plus the remaining in- dividual thread
28、s. Determine the number of threads in a repeat by analysis of the weave or dissection of the fabric. Count the number of warp threads, or the number of weave repeats, or the number of warp thread units and fractions of a unit bounded by the appropriate pair of opposite sides of the aperture. Repeat
29、with one of the edges of the aperture parallel to the weft threads, and count the number of weft threads or weave repeats or number of weft thread units in a similar manner. If the face of the fabric is composed mainly of one set of threads, as with certain twills, sateens, etc, it may be found easi
30、er to count on the back of the fabric, where the weave design is more readily recognizable. 7.2 Procedure 9 Method C - Traversing thread counter Take five specimens at random (see clause 6) 0,4 to 0,6 cm longer than the minimum measuring distance specified in clause 4 and sufficiently wide to facili
31、tate handling. Take care not to disturb the distribution of threads, especially in a loosely woven fabric. Pass the pins in the clamp (7.7.1 i through a specimen 0,2 to 0,3 cm from each end. Remove the shorter threads (those in the direction to be counted) from the specimen outside the two pins, so
32、that the measuring distance of fabric between the pins remain. Then remove the short threads from the specimen and count them. Count any threads impal.ed on a pin as half a thread. It is usually convenient to employ a pair of pointed forceps to remove the threads. The threads may be arranged in grou
33、ps of ten for convenience in counting. An approved alternative method where a clamp is not available is to insert two dissecting needles (7.1.2) the required distance apart by sliding their points down the appropriate graduation marks of a heavy steel rule (7.1.3) placed on edge. 8 Method B - Counti
34、ng glass 8.1 Apparatus 8.1.1 Counting glass, the aperture width of which shall be 2 f 0,005 cm or 3 f 0,005 cm at all places. The thickness of the base plate at the edges of the aperture shall not exceed 0.1 cm. 8.2 Procedure Use a measuring distance in accordance with clause 4. Lay the fabric flat
35、on a horizontal surface and place the count- ing glass (8.1.1) on the fabric so that one of the edges of its aperture is parallel to the warp threads. In some fabrics, it is possible to see and count every thread. If this is not possible, weave repeats may be counted. Select a thread in the weave re
36、peat which can be identified readily and position the counting glass so that this thread is adjacent to one side of the aperture of the counting glass. Count the number of 9.1 Apparatus 9.1.1 Traversing thread counter, incorporating a low- power microscope, of X 4 to X 20, mounted so that it can be
37、traversed by means of a screw over a graduated base suffi- ciently long to meet the minimum measuring distance re- quirements of clause 4. Types with an index line in the eyepiece or a pointer traversing with and visible through the microscope are equally suitable. 9.2 Test procedure Use a measuring
38、 distance in accordance with clause 4. Lay the fabric flat on a horizontal surface and place the thread counter (9.1.1) upon it in such a way that when the screw is turned the microscope moves across the fabric in a direction that is either parallel to the warp or parallel to the weft, depend- ing o
39、n which set of threads is being counted. Count the number of threads over the appropiate minimum measuring distance. In some fabrics it is possible to see and count every thread passed by the pointer or index line as it moves across the fabric. If this is not possible, weave repeats may be counted.
40、Begin counting from a thread in the weave repeat which can be read- ily identified. Count the number of whole repeats in the measuring distance, plus the remaining individual threads. Determine the number of threads in a repeat by analysis of the weave or dissection of the fabric. If the face of the
41、 fabric is composed mainly of one set of threads, as with certain twills, sateens, etc., it may be found easier to count on the back of the fabric, where the weave design is more readily recognizible. 10 Calculation and expression of results Calculate the number of threads per centimetre. Quote the
42、mean of individual results for each direction, that for the warp threads as ends per centimetre and that for the weft as picks per centimetre. The number of threads per square centimetre is given by the sum of the mean ends and picks per centimetre. Page 5 EN 1049-2 : 1993 When fabrics involving fan
43、cy weaving are patterned by small areas of 2 or more type to threads in warp and welt directions, count the number of threads of each type in a periodic pattern and then calculate the number of threads per 10 cm after meas- uring the periodicity and repeat pattern. 11 Test report The test report sha
44、ll include the following particulars: a) a reference to this International Standard (IS0 721 1 /2); b) the standard atmosphere used (temperate or tropical) ; c) the actual method used IA, B or C): di the measuring distance used; e) the number of measurements made; f) the number of warp ends per cent
45、imetre and weft picks per centimetre and the mean value of warp ends per centimetre and weft picks per centimetre. If the fabric is pat- terned by broad areas of greater and lower density, and if required, this information can be given for each different portion of the pattern. Where the number of t
46、hreads is low, it is permissible to ex- press and report the results as the number of threads per decimetre. For narrow fabrics (see clause 41, report the results as the number of threads per full width; g) if required, the number of threads per square centimetre (or square decimetre); h) details of
47、 any deviation from the method. Page 6 EN 1049-2 : 1993 Annex Method using taper and parallel line gratings (informative) A.l This method is suitable only for fabrics where thread patterns yield interference bands that are readily visible. Method D - Parallel-line grating A.l.l Principle The number
48、of interference bands produced when the parallel line grating is placed on the fabric is determined. A.1.2 Apparatus A.1.2.1 Parallel line grating, with a length of 10 or 20 cm and with about 5 % more or less lines per centimetre than there are threads per centimetre in the cloth to be tested. If se
49、veral gratings of different gauges are available, select the most suitable by trial. It is essential that the lines on the grating are straight and parallel. The average number of lines per centimetre over the whole grating shall be known to O, 1, and the average number of lines per centimetre at either edges of known length shall not differ from the general average by more than 0,15 YO. A.1.3 Procedure Place the grating selected as most suitable on the fabric with its lines parallel to the threads to be counted. If a suitable grating has been chosen, a number of bands
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