1、December 2015 English price group 12No part of this translation 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 65.160!%Ir4“2387917www.din.deDI
2、N ISO 2971Cigarettes and filter rods Determination of nominal diameter Method using a non-contact optical measuring apparatus (ISO 2971:2013),English translation of DIN ISO 2971:2015-12Zigaretten und Filterstbe Bestimmung des Nenndurchmessers Berhrungsloses optisches Messverfahren (ISO 2971:2013),En
3、glische bersetzung von DIN ISO 2971:2015-12Cigarettes et btonnets-filtres Dtermination du diamtre nominal Mthode utilisant un instrument de mesure optique sans contact (ISO 2971:2013),Traduction anglaise de DIN ISO 2971:2015-12SupersedesDIN ISO 2971:2004-12www.beuth.deDocument comprises 22 pagesDTra
4、nslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.11.15A comma is used as the decimal marker. Contents PageNational foreword .31 Scope . 52 Normative references 53 Terms and definitions . 54 Principle 65 Apparatus . 66 Sampling 77 Procedu
5、re. 77.1 Preparation of test pieces 77.2 Adjustment and calibration . 87.3 Measurement 88 Expression of results 89 Repeatability and reproducibility 910 Test report . 9Annex A (normative) Calibration standards 11Annex B (informative) Measurement principle and required number of scans . 12Annex C (in
6、formative) Information on possible source of measurement error14Annex D (informative) Non-contact measurement techniques 16Annex E (informative) Alternative measurement techniques for the determination of nominal diameter of cigarettes and filter rods 19Annex F (informative) Protocol for ISO/TC 126/
7、SC 1/WG 2 interlaboratory diameter measurement uncertainty study .21DIN ISO 2971:2015-10 2 National Annex NA (informative) Bibliography.4National foreword The text of this standard (ISO 2971:2013) has been prepared by Technical Committee ISO/TC 126 “Tobacco and tobacco products”, Subcommittee SC 1 “
8、Physical and dimensional tests” (Secretariat: AFNOR, France). The responsible German body involved in its preparation was DIN-Normenausschuss Lebensmittel und landwirtschaftliche Produkte (DIN Standards Committee Food and Agricultural Products), Working Committee NA 057-04-01 AA Tabak und Tabakerzeu
9、gnisse. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 3402 DIN ISO 3402 ISO 5725-2 DIN ISO 5725-2 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. DIN shall not be h
10、eld responsible for identifying any or all such patent rights. Amendments This standard differs from DIN ISO 2971:2004-12 as follows: a) Clause 3 “Terms and definitions” has been revised; b) non-contact measurement techniques have been brought in line with the state of the art; c) Clause 5 “Apparatu
11、s” has been revised; d) Clause 9 “Repeatability and reproducibility” has been revised and the results of the interlaboratory study have been updated; e) the information to be given in the test report has been extended; f) Annex B “Measurement principle and required number of scans”, Annex D “Non-con
12、tact measurement techniques” and Annex F “Protocol for ISO/TC 126/SC 1/WG 2 interlaboratory diameter measurement uncertainty study” have been included. Previous editions DIN 10245: 1992-03 DIN ISO 2971: 2004-12 DIN ISO 2971:2015-12 3National Annex NA (informative) Bibliography DIN ISO 3402, Tobacco
13、and tobacco products Atmosphere for conditioning and testing DIN ISO 5725-2, Accuracy (trueness and precision) of measurement methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method DIN ISO 2971:2015-10 4 Cigarettes and fil
14、ter rods Determination of nominal diameter Method using a non-contact optical measuring apparatus1 ScopeThis International Standard specifies a non contact, optical method of gauging for determination of the mean, minimum and maximum diameters and the ovality (or roundness) of rod-shaped objects wit
15、h a nominally circular or oval cross section that is convex curvilinear. The method is applicable, in particular, to cigarettes and filter rods.NOTE 1 Non-contact measurement techniques are discussed in Annex D.NOTE 2 Alternative contact or pneumatic methods may be used but should be considered as s
16、econdary methods and do not come within the scope of the standard. These alternative measurement techniques are discussed in Annex E.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated re
17、ferences, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 3402, Tobacco and tobacco products Atmosphere for conditioning and testingISO 5725-2:1994, Accuracy (trueness and precision) of measurement methods a
18、nd results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method3 Terms and definitionsFor the purposes of this International Standard, the following terms and definitions apply.3.1diameterarithmetical mean value of n apparent diameters meas
19、ured on a test piece following the method specified in this International Standard, which represents the diameter of a circle with the same circumference as the perimeter of the sample being measured, provided that the boundary of its cross section is convexNote 1 to entry: The result of the measure
20、ment can be affected by n, the number of readings taken.3.2convex cross sectiona cross section where the straight line between any two points from the section is also included within the section3.3perimeterlength of the line that is the boundary of the cross sectionNote 1 to entry: Errors will exist
21、 in the estimated value of the perimeter if the sample is not circular. The error will increase as the ovality increases.3.4circumferenceperimeter of a circular cross sectionDIN ISO 2971:2015-12 53.5minimum diameterminimum value obtained from the results of n individual readings performed on a test
22、piece3.6maximum diametermaximum value obtained from the results of n individual readings performed on a test piece3.7absolute ovalityexpression of the out-of-roundness of a rod-like test piece, which is obtained from the arithmetic difference between the maximum and minimum diameters obtained from n
23、 individual readings3.8relative ovalityratio of the absolute ovality and the diameter, expressed as a percentage3.9relative roundness100 minus relative ovalityNote 1 to entry: Caution should be exercised in interpreting maximum diameters, absolute ovality, relative ovality and relative roundness as
24、these can be affected by the quality of the gum line (raised laps) or other product defects, generating erroneous individual readings.4 PrincipleThe principle of measurement of the mean diameter of a shape having a convex cross section follows the generalization of Barbiers Theorem, which states tha
25、t the mean diameter of a section is equal to the arithmetic mean of the apparent (or projected) diameters of the section as it is rotated at equiangular intervals in the field of view. It is required that the section is rotated by an integer multiple of 180.NOTE The principle is demonstrated in Anne
26、x B.1.5 Apparatus5.1 Sample conditioning enclosure, to be capable of maintaining the conditions given in ISO 3402.5.2 Optical measuring apparatus, to consist of the following.5.2.1 Optical measuring instrumentThis must have an uncertainty of no more than 0,01 mm and be suitable for the determination
27、 of the diameter of rod-like test pieces with a nearly circular cross section. A schematic diagram of such an instrument is presented in Figure 1 and three different implementations are described in Annex D.The scanning rate of the instrument shall be such that no eccentric motion of the test piece
28、parallel to the longitudinal axis, within the measurement area, shall affect the accuracy of the measurement of mean diameter.The ratio between the scanning rate of the apparatus and the rotational speed of the test piece shall be constant and high enough to ensure that the measured diameter, as wel
29、l as the minimum and maximum values, shall be determined with sufficient accuracy, despite the possible ovality of the test piece.The length of the scan path shall be sufficiently greater than the maximum diameter to be measured to avoid errors due to test piece eccentricity. The test piece shall be
30、 scanned a minimum of 32 times during a half-rotation (180) or 64 times during a full (360) rotation.NOTE The rationale for the required number of scans is presented in Annex B.2.DIN ISO 2971:2015-10 6 5.2.2 Apparatus or fixture for rotating the test piece or scan pathThis shall rotate the test piec
31、e within the measurement area or rotate the direction of view around the test piece while maintaining the longitudinal axis of the test piece perpendicular to the measurement area during a full 360 rotation.Key1 test piece2 test piece longitudinal axis and axis of rotation3 plane of the measurement4
32、 measurement centreline5 measurement area6 test piece cross section7 projection plane8 apparent diameter (orthogonal projection or image) of the test piece cross sectionFigure 1 Diagram of a generic non-contact optical gauging system6 SamplingTake a statistically representative sample of the populat
33、ion of test pieces to be characterized.Samples shall be free of obvious visible defects which may affect the measurement.7 Procedure7.1 Preparation of test piecesCondition the test pieces, prior to measurement, in a conditioning enclosure in accordance with ISO 3402.Select at random, from the sample
34、 taken in accordance with Clause 6, the number of test pieces required for the test.DIN ISO 2971:2015-12 7The time required for the curing of filter rods and the duration of conditioning for both filter rods and cigarettes are not specified in this International Standard and are to be determined by
35、practical experience. They shall be reported in the test report together with the results.7.2 Adjustment and calibrationWorking standards are routinely used to adjust calibrate or check the calibration of the measurement system. Calibration shall be performed in accordance with the manufacturers ins
36、tructions.NOTE The essential properties of calibration standards are given in Annex A.7.3 MeasurementIn accordance with the manufacturers instructions, position the test piece within the measurement area, as close as possible to the centre of the measurement area.The test piece, or the measuring app
37、aratus, shall be capable of being rotated around the rotation axis such that any eccentric motion of the test piece, relative to the plane of the measurement, remains in parallel with the plane of the measurement and perpendicular to the longitudinal axis of the test piece.Adjust the instrument and/
38、or feeding and rotational apparatus for the plane of the measurement to measure the required section of the test piece.Operate the apparatus in accordance with the manufacturers instructions and accurately record the mean, minimum and maximum diameters.At least 10 test pieces from one sample shall b
39、e used to determine the mean value of the diameter for the sample.NOTE 1 In practice, laboratories often take a different number of measurements depending on the application of the measurement.NOTE 2 Possible sources of error in measurement of diameter are given in Annex C.8 Expression of resultsThe
40、 value of the sample mean diameter shall be the mean value of the individual measurements. See 7.3.The results shall be expressed as follows:a) diameter, the arithmetic average of at least 64 individual scans per full revolution or 32 scans per half revolution, is expressed in millimetres to the nea
41、rest 0,01 mm ;b) sample mean diameter, the average of x diameter measurements (x is normally 10 but may vary; see note 1 in 7.3) is expressed in millimetres to the nearest 0,001 mm ;c) sample maximum diameter, the maximum diameter obtained from a sample of x test pieces, is expressed in millimetres
42、to the nearest 0,01 mm ;d) sample minimum diameter, the minimum diameter obtained from a sample of x test pieces, is expressed in millimetres to the nearest 0,01 mm ;e) absolute ovality is expressed in millimetres to the nearest 0,01 mm ;f) relative ovality is expressed as a percentage to the neares
43、t 0,1 % ;g) relative roundness is expressed as a percentage to the nearest 0,1 %.DIN ISO 2971:2015-10 8 9 Repeatability and reproducibilityAn international collaborative study involving 14 laboratories was conducted according to ISO 5725-2:1994 in 2009 on matched samples of both filter rods and ciga
44、rettes covering a range of approximately 5 mm to 9 mm diameter.Each measured sample was drawn randomly from a population of typically 3000 rods that, as far as was possible, represented a consistent production process. Three samples of 10 rods, plus spares, were distributed to each participant. Each
45、 sample of 10 rods was measured once only. The measurement position for the cigarettes was specified to be on the tobacco column. The measurement position for the filters was not specified.NOTE 1 Specific details of the measurement protocol are given in Annex F.The study gave the following values (s
46、ee Table 1) for mean diameter, repeatability standard deviation (sr), reproducibility standard deviation (sR), repeatability limit (r) and reproducibility limit (R). The values derived from this interlaboratory study may not be applicable to values and matrices other than those given because the sam
47、ples being used did not cover all available products.Table 1 Summary of results of collaborative studyProduct typeMean diameter srsRr RCommentmm mm mm mm mmMono acetate filter rods, nom-inally circular cross section5,335 0,0039 0,0157 0,011 0,044 Non porous6,026 0,0031 0,0105 0,009 0,029 Non porous6
48、,780 0,0055 0,0137 0,015 0,038 Porous7,715 0,0035 0,0131 0,010 0,037 Non porous8,511 0,0059 0,0110 0,017 0,031 High porosityWhite paper cigarettes, nomi-nally circular cross section5,428 0,0104 0,0205 0,029 0,057 Unpacked6,102 0,0072 0,0156 0,020 0,044 Unpacked6,826 0,0035 0,0066 0,010 0,018 Packed7
49、,828 0,0047 0,0105 0,013 0,029 Unpacked8,612 0,0060 0,0111 0,017 0,031 UnpackedNOTE 2 The comment for filters refers to the porosity of the filter plug wrap papers, which were in the following ranges: Non porous: 10000 CORESTA Units10 Test reportThe test report shall indicate the method used and the results obtained. It shall also mention any operating conditions not specified in this International Standard, or regarded as optional, as well as any circumstances that may have influenced the results. The test report shall include all details required for
