1、BRITISH STANDARD BS ISO 6741-2:1987 Textiles Fibres and yarns Determination of commercial mass of consignments Part 2: Methods for obtaining laboratory samples ICS 59.060.01; 59.080.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBS ISO 6741-2:1987 This British Standard, hav
2、ing been prepared under the direction of the Materials and Chemicals Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 21 May 2002 BSI 21 May 2002 ISBN 0 580 39666 5 National foreword This British Standard reproduces verbatim IS
3、O 6741-2:1987 and implements it as the UK national standard. It supersedes BS 4784-2:1988 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee TCI/24, Physical testing of textiles, which has the responsibility to: A list of organizations represented on thi
4、s committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, o
5、r by using the “Find” facility of the BSI Standards Electronic Catalogue. 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
6、immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate
7、them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, the ISO foreword page, pages 1 to 5 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication
8、Amd. No. Date CommentsINTERNATIONAL STANDARD INTERNATIONAL ORGANIZATION FOR STANDARDIZATION ORGANISATION INTERNATIONALE DE NORMALISATION MEXAYHAPOAHAfl OPTAHM3AVlR I-IO CTAHAPTM3AMM Textiles - Fibres and yarns - Determination of commercial mass of consignments - Part 2 : Methods for obtaining labora
9、tory samples Textiles - Fibres et fills - Ddtermination de la masse commerciale dun lot - Partie 2: Mkhodes dob ten tion des khan tillons pour labora toire IS0 6741-2 First edition 1987-04-M R eference number I IS0 6741-2: 1987 (E) Foreword IS0 (the International Organization for Standardization) is
10、 a worldwide federation of national standards bodies (IS0 member bodies). The work of preparing International Standards is normally carried out through IS0 technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represen
11、ted on that committee. International organizations, govern- mental and non-governmental, in liaison with ISO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standa
12、rds by the IS0 Council. They are approved in accordance with IS0 procedures requiring at least 75 % approval by the member bodies voting. International Standard IS0 6741-2 was prepared by Technical Committee ISO/TC 38, Textiles. Users should note that all International Standards undergo revision fro
13、m time to time and that any reference made herein to any other International Standard implies its latest edition, unless otherwise stated. 0 lanoitanretnI noitazinagrO rof ,noitazidradnatS 7891 detnirP ni dnalreztiwS - INTERNATIONALSTANDARD IS0 6741-2 : 1987 (E) - Fibres and yarns - Determination of
14、 cial mass of consignments - Part 2 : Methods for obtaining laboratory samples 0 Introduction The procedures comprise : This document forms part 3 of a four-part International Stan- dard prepared by ISO/TC 38, Textiles. Nature of consignment Procedure described b Part 1 : Mass determination and calc
15、ulations. Bulk staple in bales Part 2: Methods for obtaining laboratory samples. Part 3: Specimen cleaning procedures. Part 4: Values used for the commercial allowances and the commercial moisture regains. (Technical Report.) Tow and strands in bales and cases Unsupported wound or coiled packages of
16、 raw silk, tow sliver, top or yarn in containers The terminology used in this International Standard is in ac- cordance with IS0 6348. Yarn wound on supports Most contracts of sale between buyer and seller specify either that the invoice mass of a consignment shall be determined by an independent th
17、ird party, or that the sellers figuremay be subject to an independent third-party check. This part of IS0 6741 describes the methods which are to be used by the in- dependent third party in these cases. The figure for the com- mercial mass which results from the application of the pro- cedures in th
18、is part of IS0 6741 either becomes the invoice mass of the consignment or is compared with the declared invoice mass plus or minus the tolerance agreed between the buyer and seller. When a replicate sample is required for other tests or as a pre- caution against misadventure, the mass taken during s
19、ampling shall be doubled and the sample shall then immediately be halved to provide the two samples. 2 References IS0 6348, TextlJles - Determination of mass - Vocabulary. It is not intended that the methods in this part of IS0 6741 necessarily be used by the seller to establish his invoice mass. IS
20、0 6741, Textiles - Fibres and yarns - Determination of commercial mass of consignments - Part I : Mass determination and calculations. The methods described in this part of IS0 6741 are, for the most part, destructive. - Part 4 : Values used for the commercial allowances and the commercial moisture
21、regains. (Technical Report.) 1 Scope and field of application This part of IS0 6741 specifies methods for obtaining laboratory samples for mass determination by one of the methods given in IS0 6741-1. The method appropriate for par- ticular fibres is indicated in IS0 6741-4 3 Principle Laboratory sa
22、mples are taken from the containers in the consignment samples obtained as specified in IS0 6741-1 and placed in stoppered, air-tight vessels for subsequent process- ing. Hand sampling (two methods) Core sampling Hand sampling Hand sampling Cutting method Winding (four methods) 1 IS0 6741-2 : 1987 (
23、E) 4 Apparatus Air-tight vessels, of low hygroscopicity and known mass, capable of holding the material being tested. For example, a stoppered glass jar or a clean, grease-free polyethylene bag of minimum thickness 70 pm, inside a second similar polyethylene bag, is sometimes used. In the latter cas
24、e, both bags shall be sealed and free of holes. 5 Sampling procedure Sample, preferably immediately after weighing each container in the consignment sample as specified in 6.2 of IS0 6741-1, in accordance with 5.1, 5.2 or 5.3, as appropriate. 5.1 Consignments of bulk staple in bales 5.1.1 Method A R
25、emove the bale wrappers. Take samples from the bale in such a manner that - each sample is taken from the appropriate zone described below; - no more than 30 s elapse between the exposure of a sample and its confinement in an air-tight vessel (clause 4). Samples may be taken with a hook, but any han
26、dling shall be carried out with gloves of an impervious material. 1 I i -m- f -+-=Y I I I I I I I I I I I I I I I I I t- - l c / I I / I I / / I IL -e- 4 Consider the bale as being made up of two zones, inner and outer, both of about the same volume (see figure I). The dimensions of the inner zone s
27、hall be 80 % of those of the bale, i.e. the thickness of the outer layer represents 10 % of the cor- responding dimension of the bale. a) From the outer zone take 12 samples, each weighing about 5 g, two being taken from each face at randomly dif- ferent positions and depths within the layer. b) Fro
28、m the inner zone take a further six samples, each weighing about 10 g. Consider the inner zone to be made up of six equal layers (see figure 21, three layers above and three layers below the centre line of the bale, and take one sample at random from each of these layers. As each sample is taken fro
29、m the bale, place it immediately into a pre-weighed, air-tight vessel. There should finally be about 120 g of fibre in the vessel. 5.1.2 Method B Remove the bale wrappers. Use a hand sampling method similar to that described in 5.1 .I. Employ three distinct points of sampling situated on a diagonal
30、line of the parallelepiped constituted by the bale and positioned at 20 %, 50 % and 80 % of its length. Take one sample, mass at least 150 g, at each point and place it immediately into a pre- weighed, stoppered, air-tight vessel (clause 4). The mass of the staple in the vessel should finally be abo
31、ut 500 g. Figure 1 - Zones of a bale Figure 2 - Layers of inner zone 2 IS0 6741-2 : 1987 (E) 5.1.3 Method C Select and use one of the following methodsl). 5.1.3.1 Method Cl Use a core sampler with a non-rotating coring tube with manual pressure. The diameter of the cutting tip (which shall be sharp
32、to achieve good bale penetration) shall be 12 to 25 mm and the tube length shall be 600 + 20 mm. Clear the point of tube penetration and insert the corer in a direction which is parallel to the sides of the bale in the direc- tion of compression to a depth of not less than 47 % of the bale length. E
33、xtract not less than 35 core samples at random from the con- signment sample in accordance with table 1. Place the samples from each bale immediately into a pre-weighed, stoppered, air- tight vessel. Use either one vessel per bale or, if a global sample is to be used, one or more large vessels betwe
34、en which all the cores from all the containers are equally divided. Table 1 - Coring programme for bales, method Cl Number of bales in the consignment sample 1 2 3 4 5 6 7, 8 9, 10, 11 12 to 17 18 to 34 35 and above Number of cores per bale Number of cores from each face of the bale* 35 18 12 9 7 6
35、5 4 3 2 1 18/17 919 6/6 5/4 4/3 313 3/2 212 2/l l/l l/O * Core alternately through the cap and base. 5.1.3.2 Method C2 Use a core sampler with a non-rotating coring tube with mechanical pressure. The diameter of the cutting tip (which shall be sharp to achieve good bale penetration) shall be 18 + 1
36、mm21 and the tube length shall be sufficient to achieve - a depth of penetration of at least 90 % of the bale length. Clear the point of tube penetration on the base of the bale and insert the corer in a direction which is parallel to the sides of the bale in the direction of compression to the full
37、 depth of the tube. Extract not less than 20 core samples at random from the con- signment sample in accordance with table 2. Place the samples from each bale immediately into a stoppered, air-tight vessel. Use either one vessel per bale or, if a global sample is to be used, one or more large vessel
38、s between which all the cores from all the containers are equally divided. In the case of high-density bales (more than 450 kglms), spe- cial equipment shall be employed. The commercial mass of high-density bales can nevertheless be determined by partial or complete removal of wrappers, followed by
39、methods B, Cl and C2. Table 2 - Coring programme for bales, method C2 Number of bales in the consignment sample Number of cores per bale 1 20 2 10 3 7 4 5 5, 6 4 7, 8, 9 3 10 to 19 2 20 and above 1 5.1.3.3 Method C3 Use a core sampler with a non-rotating coring tube with manual pressure. The diamete
40、r of the cutting tip (which shall be sharp to achieve good bale penetration) shall be 25 + 1 mm and the tube length shall be 600 + 20 mm. Clear the point of tube penetration and insert the corer in a direction which is parallel to the sides of the bale in the direc- tion of compression to a depth of
41、 about 90 % of the bale length. Extract from each bale the number of cores indicated in table 3. Place the samples from each bale immediately into a pre- weighed, stoppered, air-tight vessel (clause 3). Use either one vessel per container or, if a global sample is to be used, one or more large vesse
42、ls between which all the cores from all the con- tainers are equally divided. Table 3 - Coring programme for bales, method C3 1) Methods Cl and C2 are based upon the IWO manual and machine coring procedures respectively. 2) The interested parties may agree to use a cutting tip with a diameter betwee
43、n 12 and 25 mm. 3 IS0 6741-2 : 1987 (E) 5.2 Consignments of tow and strands in bales or cases For supported packages, determine the total mass of the sup- ports and wrappings to permit the calculation of the net mass of the container (see sub-clause 6.2 of IS0 6741-I). As with staple fibre, wear imp
44、ervious gloves when handling the material. 5.2.1 Method D Take a sample of about 30 g from the material at the top of the bale or case. Take three further samples, each of about 20 g, from the interior of the bale, at points P, Q, and R in a middle t. layer of the bale shown in figure 3. One point i
45、s at the centre of the layer and the other two half-way between the centre and the surface of the bale. Access to this middle layer may be ob- tained either by winding off or by lifting off the upper layers. Take a fifth sample (of about 30 g) tom of the bale or case. from the material at the bot- F
46、igure 3 - Tow in bale Take the samples immediately after exposing the surface con- cerned, with a maximum delay of 30 s. As each sample is taken from a single bale or case, place it immediately into a pre- weighed air-tight vessel (clause 3). There should finally be about 120 g of fibre in the vesse
47、l. 5.3 Consignments of tow, sliver or top delivered as wound or coiled packages in con ltainers 5.3.1 Method E Tow, sliver and top may be delivered as wound or coiled packages, with or without support or wrapping, with a number of such packages in each container of the consignment. From each of the
48、containers to be sampled take one package (two in the case of wool) entirely at random, and from a dif- ferent part of each container. As for staple, wear impervious gloves when handling the material. Unwrap each unit package and immediately take about 30 g of fibre (60 g in the case of wool) from i
49、ts outer surface. Then cut or divide each package in order to reach its middle and take 60 g (120 g in the case of wool) from here. Continue cutting or dividing to the end of each package and take a final 30 g sample (60 g in the case of wool). Place each sample immediately into a pre-weighed air-tight vessel (clause 4) within 30 s of ex- posure. There should finally be about 120 g fibre (480 g in the case of wool, half from each package) in the vessel. 5.4 Consignments of yarn on packages From each of the containers to be sampled take one package random, a
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