1、Designation: D 1447 07Standard Test Method forLength and Length Uniformity of Cotton Fibers byPhotoelectric Measurement1This standard is issued under the fixed designation D 1447; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、 year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the measurement of the lengthand length uniformity of cotton fibers by use of photoe
3、lectricmeasurement. The test method is applicable to fibers takenfrom raw or partially processed cotton (up to card mat) or sometypes of cotton waste, but not to fibers from blends of cottonwith other fibers or to fibers recovered from cotton yarns,fabrics or to 100 % systhetic fibers.1.2 This test
4、method is especially adapted for determiningthe length and length uniformity of cotton fibers by models ofthe Digital Fibrograph, hereafter referred to as Fibrograph.NOTE 1Instructions for the use of Manual and Servo FibrographModels were included in the text of Test Method D 1447 in 1971 andpreviou
5、s editions.NOTE 2For other methods covering the measurement of the length ofcotton fibers refer to Test Method D 1440.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesa
6、fety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 123 Terminology Relating to
7、TextilesD 1440 Test Method for Length and Length Distribution ofCotton Fibers (Array Method)D 1441 Practice for Sampling Cotton Fibers for TestingD 1776 Practice for Conditioning and Testing TextilesD 3025 Practice for Standardizing Cotton Fiber Test Resultsby Use of Calibration Cotton StandardsD 71
8、39 Terminology for Cotton Fibers3. Terminology3.1 For all terminology related to D13.11, refer to Termi-nology D 7139.3.1.1 amount, nin cotton length testing with the Fib-rograph, a measure of the thickness, or optical density, of thetest beard, proportional to the number of fibers present atvarious
9、 distances from the comb(s).3.1.2 fibrogram, nin cotton length testing with the Fib-rograph, the curve representing the second cumulation of thelength distribution of the fibers sensed by the length measuringinstrument in scanning the fiber board.3.1.3 mean length, nin testing of cotton fibers, the
10、averagelength of all the fibers in the test specimen based on mass-length data.3.1.4 span length (Fibrograph), nthe distance spanned bya specified percentage of the fibers in the test beard, taking theamount reading at the starting point of the scanning as 100 %.3.1.5 test beard, nin length testing
11、of cotton, the portionof the test specimen that has been combed and brushed into a“beard” which protrudes from the outside of the comb(s) or theclamp(s).3.1.6 test specimen (Fibrograph), nthe cotton fibersplaced randomly on a Fibrograph comb(s) for fiber lengthmeasurements.3.1.7 uniformity index, ni
12、n cotton length testing with theFibrograph, the ratio between two span lengths expressed as apercentage of the longer length.3.1.8 uniformity ratio, nin cotton length testing with theFibrograph, the ratio between two span lengths expressed as apercentage of the longer length.3.1.8.1 DiscussionVariou
13、s span lengths and measures oflength uniformity may be calculated from the results of themeasured points, but the 2.5 and 50 % span lengths and the50/2.5 uniformity ratio are usually used.3.1.9 upper-half-mean length, nin fiber length testing ofcotton, the mean length by number, of the longer one ha
14、lf ofthe fibers by weight.1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.11 on Cotton Fibers.Current edition approved Dec. 1, 2007. Published January 2008. Originallyapproved in 1955. Last previous edition approved in
15、 2000 as D 1447 00.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Ha
16、rbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2 For definitions of other textile terms used in this method,refer to Terminology D 123.4. Summary of Test Method4.1 Fibers are placed on comb(s) in such a way that they arecaught at random points along their lengths to form
17、a beard.The beard is scanned photoelectrically from base to tip, theamount of light passing through the beard being used as ameasure of the number of fibers that extend various distancesfrom the comb(s).4.2 The Fibrograph shows the amount and the lengthreadings from the Fibrogram being sensed on sep
18、arate dials.5. Significance and Use5.1 This test method is considered satisfactory for accep-tance testing when the levels of the laboratories are controlledby the use of the same reference standard cotton samplesbecause the current estimates of between-laboratory precisionare acceptable under these
19、 conditions. If there are differencesof practical significance between reported test results for twoFIG. 1 Digital Fibrograph, Model 730FIG. 2 FibrosamplerD1447072laboratories (or more), comparative tests should be performedto determine if there is a statistical bias between them, usingcompetent sta
20、tistical assistance. As a minimum, ensure the testsamples to be used are as homogeneous as possible, are drawnfrom the material from which the disparate test results wereobtained, and are randomly assigned in equal numbers to eachlaboratory for testing. The test from the two laboratories shouldbe co
21、mpared using a statistical test for unpaired data, at aprobability level chosen prior to the testing series. If a bias isfound, either its cause must be found and corrected, or futuretest results for that material must be adjusted in considerationof the known bias.5.2 Fibrograph measurements provide
22、 a relatively fastmethod for determining the length and length uniformity of thefibers in a sample of cotton in a reproducible manner.5.3 Results of the Fibrograph length tests do not necessarilyagree with those obtained by other methods for measuringlengths of cotton fibers because of the effect of
23、 fiber crimp andother factors.5.4 Fibrograph tests are more objective than commercialstaple length classifications and also provide additional infor-mation on fiber length uniformity of cotton fibers. The cottonquality information provided by these results is used inresearch studies and quality surv
24、eys, in checking commercialstaple length classifications, in assembling bales of cotton intouniform lots, and for other purposes.5.5 Fibrograph measurements are based on the assumptionsthat a fiber is caught randomly along its length.6. Apparatus6.1 Fibrograph,3digital model, with accessory equipmen
25、tas shown in Fig. 1.6.2 Fibrosampler, for the preparation of test specimens(required) as shown in Fig. 2.7. Sampling7.1 Division into LotsFor acceptance testing purposes, thepurchaser and the supplier shall agree on what materialconstitutes a lot.7.2 Lot SampleAs a lot sample for acceptance testing,
26、take at random the number of shipping containers directed inan applicable material specification or other agreement be-tween the purchaser and the supplier, such as an agreement touse Practice D 1441.7.3 Laboratory SampleAs a laboratory sample for accep-tance testing, select and prepare a 30 to 50 g
27、 (1 to 2 oz)subsample from each of the shipping containers in the lotsample, proceeding as directed in Practice D 1441 using eitherthe blended sample procedure or the subsample procedure asagreed between the purchaser and the supplier.7.4 Test SpecimensAs directed in Section 10, prepareeither two or
28、 four specimens from each subsample in thelaboratory sample. For acceptance testing, test either two orfour specimens from each subsample in the laboratory sampleas agreed between the purchaser and the supplier.8. Preparation and Adjustment of Apparatus8.1 Set up the Fibrograph and adjust it as dire
29、cted in themanufacturers instructions for the model being used.8.2 Set up and adjust the Fibrosampler as directed in themanufacturers instructions.8.3 Before making Fibrograph length tests, allow the instru-ment to warm up until it is electronically stable (5 minutes),then carefully check it both el
30、ectronically and mechanically byusing the methods listed in 8.3.1-8.3.4 for specific items.8.3.1 When the Fibrograph is first powered on, the LEDs onthe front of the instrument will display the units systeminformation. After the system information is displayed, thecomb transport moves from the start
31、 to the stop position to zerothe optics. Once the comb transport has returned to the startposition, lift the door and adjust the optics by following themanufacturers instruction.8.3.2 The Fibrograph calibration should be checked once aweek. During calibration check the calibration values are notchan
32、ged. When a calibration is performed, the calibrationvalues will be changed. A metal length standard with a knownlength value is supplied with the Fibrograph for calibrationpurposes. Follow the calibration procedures as directed in themanufacturers instructions.8.3.3 Measure specimens of cotton fibe
33、rs from a laboratorycontrol sample with established length values (Note 3). Eachtechnician must measure separate specimens prepared from alaboratory control sample and obtain acceptable length resultsbefore performing similar measurements on specimens fromunknown samples. When unacceptable results a
34、re obtainedfrom the laboratory control sample, recheck the instrumentadjustments and the testing techniques until acceptable resultsare obtained (Note 4).NOTE 3Standard calibration cotton samples for Fibrograph lengthtests are available from the Cotton Division, Agricultural MarketingService, U.S. D
35、epartment of Agriculture, 3275 Appling Road, Memphis,TN 38133, or other cottons may be used for routine calibration afterextensive tests in comparison with USDA calibration samples haveestablished the test values and the uniformity of the material. See PracticeD 3025.NOTE 4The Fibrograph length resu
36、lts obtained are affected by theamount of combing performed on the specimens. Operators quickly learnthrough practice the sampling process and the amount of brushingrequired to obtain acceptable results for the tests on the laboratory controlsamples for the instrument being used.8.3.4 Make additiona
37、l length measurements of specimenstaken from the laboratory control sample at least every 2 hduring the day to maintain a continuing check on the level ofresults.9. Conditioning9.1 Before preparing the specimens, bring the laboratorysample from the prevailing atmosphere to moisture equilibriumfor te
38、sting in the standard atmosphere for testing textilesaccording to Practice D 1776. Preconditioning is not necessary.10. Preparation of Specimens10.1 Fibrosampler Method (Fig. 2):3Instruments and accessories meeting these requirements may be obtained fromUster Technologies, Inc., 456 Troy Circle, P.
39、O. Box 51270, Knoxville, TN37919-1270.D144707310.1.1 From a sample of fibers, select a subsample ofapproximately 25 grams or more (two handfuls). Place it in theFibrosampler cylinder. Insert the comb into the Fibrosamplercombholder. With a circular motion of the left hand, press thefibers so they pr
40、otrude through holes of the sample plate,maintaining and evenly distributed pressure over the surface.Then relax the pressure of the left hand so the fibers can beeasily pulled through the plate holes by the teeth of the comb.Take the loaded comb from the Fibrosampler, turn the samplearound to prese
41、nt a new surface to the perforated plate. If asecond comb is required, repeat the load procedure describedabove.10.1.2 Clean the card clothing on the Fibrosampler eachtime you change samples. This will avoid having the cottonthat has built up on the card cloth contaminate the new sampleand possibly
42、skewing the test results. Cotton should also beremoved from the cleaning brush as required. To do this, usethe cleaning brush provided with the equipment.11. Procedure11.1 After the Fibrograph is in proper operating condition(see 8.3) and the correct sampling procedure has been estab-lished, insert
43、the loaded comb(s) into the combholder of theFibrograph with the beard of fibers pointing downward. Brushthe fibers with firm strokes of the Fibrograph brush to removeloose fibers, to straighten the other fibers without disturbingtheir distribution in the teeth of the comb(s), and thus completeprepa
44、ration of the specimen. It is important that each sample isbrushed properly so that consistent test results can be achieved.11.2 Lower the lens assembly (close the door) The combtransport will move the sample across the optics to measure thesample.11.3 Test either two or four specimens from each sub
45、samplein the laboratory sample, depending on the precision desired,and if possible have two technicians participate with each onetesting one half the number of specimens.11.4 Read the upper-half-meanlength values in millimetresdirectly from the LED display of the Fibrograph.11.5 Read the uniformity
46、index in percent directly from theLED display of the Fibrograph. A switch in the back of theinstrument allows choosing which value is displayed on theLED display.11.6 Read the short fiber index (SFI) value in percentdirectly from the LED display on the Fibrograph.12. Report12.1 State that the specim
47、ens were tested as directed in TestMethod D 1447. State the number of specimens tested for eachsubsample.12.2 Report the following information:12.2.1 Designation of the length and uniformity indexvalues reported, such as upper-half-mean length (UHML),mean length (ML), uniformity index (ML/UHML) and
48、shortfiber index (SFI).12.2.2 The average length, uniformity index and short fiberindex.12.2.3 The source of the cotton fibers taken for testing, suchas raw or partially processed cotton (up to card mat) or type ofcotton waste.13. Precision and Bias13.1 The precision of this test method is based on
49、anInterlaboratory study of Test Method D 1447 conducted in2007. Each of ten laboratories tested nine materials (fivereplicates each) covering four analyses to determine theintralaboratory and interlaboratory precision of Test MethodD 1447.413.1.1 RepeatabilityTwo test results obtained within onelaboratory shall be judged not equivalent if they differ by morethan the “r” value for that material; “r” is the intervalrepresenting the critical difference between two test results forthe same material, obtained by the same operator using thesame equipment on the same
