1、BRITISH STANDARDBS EN 14621:2005Textiles Multifilament yarns Methods of test for textured or non-textured filament yarnsThe European Standard EN 14621:2005 has the status of a British StandardICS 59.080.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49
2、g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 14621:2005This British Standard was published under the authority of the Standards Policy and Strategy Committee on 16 January 2006 BSI 16 January 2006ISBN 0 580 ? ?National forewordThis Br
3、itish Standard is the official English language version of EN 14621:2005.The UK participation in its preparation was entrusted to Technical Committee TCI/24, Textiles, physical testing, which has the responsibility to: A list of organizations represented on this committee can be obtained on request
4、to its secretary.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electro
5、nic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to unde
6、rstand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK.Summary of pagesThis document comprises a f
7、ront cover, an inside front cover, the EN title page, pages 2 to 19 and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14621Decembe
8、r 2005ICS 59.080.20English VersionTextiles - Multifilament yarns - Methods of test for textured ornon-textured filament yarnsTextiles - Multifilaments - Mthodes dessais pour la frisuredes fils multifilaments texturs et le retrait thermique desfils plats et texturesTextilien - Multifilamentgarne - Pr
9、fverfahren fr texurierteund nicht texturierte MultifilamentgarneThis European Standard was approved by CEN on 26 October 2005.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard wi
10、thout any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards 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 m
11、ade by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, G
12、reece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre:
13、rue de Stassart, 36 B-1050 Brussels 2005 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14621:2005: EEN 14621:2005 (E) 2 Contents page Foreword 3 1 Scope.4 2 Normative references .4 3 Terms and definitions.4 4 Test methods.5 5 Test
14、report .14 Annex A (informative) Calculation of the length of yarn to be reeled16 Bibliography.19 EN 14621:2005 (E) 3 Foreword This European Standard (EN 14621:2005) has been prepared by the Technical Committee CEN /TC 248 “Textiles and Textile Products“, the secretariat of which is held by BSI. Thi
15、s 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 June 2006, and conflicting national standards shall be withdrawn at the latest by June 2006. According to the CEN/CENELEC Internal Regulations, the nat
16、ional standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, P
17、ortugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 14621:2005 (E) 4 1 Scope This European Standard specifies test methods for quality control of textured and non-textured multifilament synthetic yarns. It includes the following test methods: determination of the crimp con
18、traction - textured multifilament yarn with linear density up to 500 dtex; determination of the hot air shrinkage - for non-textured and textured multifilament yarns; determination of the boiling water shrinkage - for non-textured and textured multifilament yarns. 2 Normative references The followin
19、g referenced documents are indispensable for the application of this European Standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN ISO 139, Textiles Standard atmospheres for condit
20、ioning and testing (ISO 139:2005) 3 Terms and definitions For the purposes of this European Standard, the following terms and definitions apply. 3.1 crimp contraction contraction of a textured filament yarn resulting from the development of crimp, expressed as a percentage of its original length, wi
21、th the lengths of the contracted and straightened yarns measured under specified tensions 3.2 thermal shrinkage decrease in length of a textured or non-textured filament yarn as a result of a thermal treatment (boiling water or hot air), expressed as a percentage of its original length 3.3 linear de
22、nsity mass per unit length of a multifilament yarn as defined in EN ISO 2060 3.4 tension tensile force applied to the specimen, generally related to its linear density 3.5 pre-tension tension applied to a specimen at the beginning of certain tests 3.6 straightened length length of the specimen measu
23、red under a high tensile force, which straightens the skein without stretching 3.7 contracted length of textured yarn length of the specimen measured under a low tensile force after a specified recovery time has elapsed EN 14621:2005 (E) 5 3.8 package form of presentation of the multifilament yarn,
24、e.g. spool, cheese, cone, bobbin etc. 3.9 multifilament yarn yarn composed of several filaments 4 Test methods 4.1 Determination of the crimp contraction 4.1.1 Principle The crimp of a specimen of a textured filament yarn in the form of a skein of known nominal linear density is developed by treatme
25、nt with hot air while the specimen is subjected to a low tensile force. After reconditioning, the straightened length of the skein is measured under a high tensile force. After a specified recovery time, the contracted length of the skein, shortened by the effect of the yarn crimp, is measured under
26、 the low tensile force. Crimp contraction is calculated as the difference between the two length values related to the straightened length. 4.1.2 Apparatus 4.1.2.1 Reel A reel with a circumference of (1 000 2,5) mm is used for winding the yarn skeins. The reel shall be fitted with a device to provid
27、e the specified tensile force per unit linear density to the material being wound on with the maximum possible accuracy and to maintain the separation between a number of skeins wound at the same time. 4.1.2.2 Automatic testing device A suitable testing device (see Figure 1) uses a loading apparatus
28、, which extends the skein at a speed of (1 000 10) mm/min until the pre-set tensile force is reached at which the yarn crimp is pulled out, and which determines the straightened skein length related to that tensile force. NOTE The speed of the loading apparatus may be reduced e.g. in case of less ex
29、tensible textured yarns, for example to 250 mm/min, provided that this is clearly stated in the test report. Only test results obtained with identical speeds may be compared. The same apparatus determines in a second measurement the contracted length of the skein under a low tensile force provided b
30、y a pre-tension weight attached to the skein or a hook-shaped pre-tension weight attached to the skein. Resolution of the length measurement is 0,05 mm or better. A number of skeins are arranged in a holder, with the skeins being tested in succession. The holder can be removed from the automatic tes
31、ting device. EN 14621:2005 (E) 6 12345Key 1 Specimen holder 2 Specimen 3 Pre-tension weight (e.g. an S-shaped hook) 4 Loading apparatus and length measuring system 5 Force measuring system Figure 1 Automatic testing device 4.1.2.3 Oven with forced ventilation The oven shall be suitable for a heat tr
32、eatment of the test specimens arranged in the holder of the automatic testing device at 120 C. The temperature variation from the set value shall not exceed 4 C in the immediate vicinity of the specimens. The utilizable space shall have a height of at least 600 mm and suitable width and depth to acc
33、ommodate the holder of the automatic testing device in an upright position, so that the skeins can hang perfectly. The oven shall be operated with forced air circulation. EN 14621:2005 (E) 7 4.1.3 Conditioning and preparation of the test specimens Take off at least 500 m from the packages representi
34、ng the laboratory samples before preparing the test specimens. Prior to testing, the specimens are exposed for at least 24 h to the standard atmosphere according to EN ISO 139. To permit the use of the same linear density related tensile forces for yarns of different linear density, a skein is produ
35、ced having a linear density of about 2 500 dtex (250 tex) by winding a corresponding length of yarn onto a reel. While the yarn is being reeled, a tensile force per unit linear density of 2 cN/tex 10 % shall be maintained as uniformly as possible. (See Annex A for the calculation of the length of ya
36、rn to be reeled.) The two yarn ends shall then be tied together, but in such a way that stretching of the yarn is avoided. When suspending the skeins from the specimen holder, the knots are placed at the suspension hooks. Throughout the sampling and conditioning procedures, particular care should be
37、 taken that any stress applied to the specimens in the course of handling does not exceed the tensile force applied during reeling. 4.1.4 Procedure After the skein is removed from the winding reel, it is suspended from the holder of the automatic testing device, and a tension weight of 2,5 cN (e.g.
38、an S-shaped hook) is attached to the skein to produce the required tensile (force per unit linear density of 0,01 cN/tex) which remains on the skein throughout the whole testing procedure. Following this, the holder with the skeins is placed into the oven preheated to a temperature of (120 4) C, wit
39、h its forced air circulation in operation, and is kept there for a period of 10 min 20 s to develop the crimp. Placing the holder into the oven shall be carried out within a time of 5 s to 10 s to minimize the temperature drop in the oven. When the crimp development time has elapsed, the holder with
40、 the specimens is removed from the oven and exposed again to the standard atmosphere for 24 h for reconditioning and relaxation. NOTE 1 The period of conditioning the specimens after reeling as well as after the heat treatment may be reduced, e.g. to 30 min, provided that this is clearly stated in t
41、he test report. Only test results obtained with identical conditioning periods may be compared. NOTE 2 Polypropylene or polyethylene may be tested under different conditions of time and temperature, provided that this is clearly stated in the test report. Only test results obtained under identical t
42、est conditions may be compared. To determine the straightened length L0, the holder with the specimens is placed into the automatic testing device tester. Thereafter, starting with the first specimen in the holder, the loading apparatus gradually extends the skein until a tensile force of 500 cN (i.
43、e. 2 cN/tex 5 %) is reached. This force is maintained for (10 1) s, and after this, the straightened length L0is measured. Following the determination of the straightened length, the loading apparatus travels in the opposite direction to release the tensile force on the skein. The specimen holder no
44、w turns to the next position, and the loading apparatus subjects the next skein to the same tensile force. After all specimens in the holder have been tested, and after a relaxation period of 10 min 20 s has elapsed, the contracted length L1of each skein under the pre-tension weight of 2,5 cN is mea
45、sured by the same loading apparatus. EN 14621:2005 (E) 8 4.1.5 Calculation and expression of the results The crimp contraction, CC, expressed in percent, is calculated from the following equation: 010100LLLCC= (%) where L0 is the straightened length; L1 is the contracted length. 4.2 Determination of
46、 the hot air shrinkage 4.2.1 Principle Skeins of known nominal linear density are subjected to a low tensile force and treated with hot air at a specified temperature for a specified time. The skein length is measured under a specified tensile force suitable to straighten the skein before and after
47、the heat treatment. Shrinkage is calculated as the difference between the two length values related to the length before the heat treatment. 4.2.2 Apparatus 4.2.2.1 Reel A reel with a circumference of (1 000 2,5) mm is used for winding the yarn skeins. The reel shall be fitted with a device to provi
48、de the specified tensile force per unit linear density to the material being wound on with the maximum possible accuracy and to maintain the separation between a number of skeins wound at the same time. 4.2.2.2 Automatic testing device A suitable testing device uses a loading apparatus, which extend
49、s the skein with a speed of (1000 10) mm/min for textured yarn or (250 10) mm/min for non-textured yarn until the preset tensile force is reached at which the skein is straightened. The device determines the initial length of the skein at this tensile force. The same apparatus determines in a second measurement the length of the skein in the shrunken state (after treatment of the skein in the oven) under a low tensile force provided by a pre-tension weight attached to the skein. Resolution of the length measurement is 0,05 mm
