1、Designation: D 1447 071Standard 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, th
2、e year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEUpdated research report information in Footnote 4 editorially in June 2009.1. Scope1.1 This test method covers the
3、measurement of the lengthand length uniformity of cotton fibers by use of photoelectricmeasurement. 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
4、 recovered from cotton yarns,fabrics or to 100 % systhetic fibers.1.2 This test 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 Fib
5、rographModels were included in the text of Test Method D 1447 in 1971 andprevious 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 inc
6、luded in thisstandard.1.4 This standard does not purport to address all of thesafety 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
7、to use.2. Referenced Documents2.1 ASTM Standards:2D 123 Terminology Relating to 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 S
8、tandardizing Cotton Fiber Test Resultsby Use of Calibration Cotton StandardsD 7139 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 d
9、ensity, of thetest beard, proportional to the number of fibers present atvarious 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 i
10、n scanning the fiber board.3.1.3 mean length, nin testing of cotton fibers, the 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 t
11、he starting point of the scanning as 100 %.3.1.5 test beard, nin length testing 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
12、 on a Fibrograph comb(s) for fiber lengthmeasurements.3.1.7 uniformity index, nin 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 spa
13、n lengths expressed as apercentage of the longer length.3.1.8.1 DiscussionVarious 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.1This test method is under the j
14、urisdiction 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 2000 as D 1447 00.2For referenced ASTM standards, visit t
15、he 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 Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,
16、 United States.3.1.9 upper-half-mean length, nin fiber length testing ofcotton, the mean length by number, of the longer one half ofthe fibers by weight.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)
17、 in such a way that they arecaught at random points along their lengths to form 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 Fibrograp
18、h shows the amount and the lengthreadings from the Fibrogram being sensed on separate 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
19、 the current estimates of between-laboratory precisionare acceptable under these conditions. If there are differencesof practical significance between reported test results for twolaboratories (or more), comparative tests should be performedto determine if there is a statistical bias between them, u
20、singcompetent statistical assistance. As a minimum, ensure the testFIG. 1 Digital Fibrograph, Model 730FIG. 2 FibrosamplerD14470712samples 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 numb
21、ers to eachlaboratory for testing. The test from the two laboratories shouldbe compared 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
22、be adjusted in considerationof the known bias.5.2 Fibrograph measurements provide 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 obtaine
23、d by other methods for measuringlengths of cotton fibers because of the effect of 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
24、information provided by these results is used inresearch studies and quality surveys, 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 al
25、ong its length.6. Apparatus6.1 Fibrograph,3digital model, with accessory equipmentas 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 wha
26、t materialconstitutes a lot.7.2 Lot SampleAs a lot sample for acceptance testing,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 Samp
27、leAs a laboratory sample for accep-tance testing, select and prepare a 30 to 50 g (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 a
28、nd the supplier.7.4 Test SpecimensAs directed in Section 10, prepareeither two or 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. Prepa
29、ration and Adjustment of Apparatus8.1 Set up the Fibrograph and adjust it as directed 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
30、 up until it is electronically stable (5 minutes),then carefully check it both electronically 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.
31、After the system information is displayed, thecomb transport moves from the start 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 b
32、e checked once aweek. During calibration check the calibration values are notchanged. 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
33、 directed in themanufacturers instructions.8.3.3 Measure specimens of cotton fibers 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 s
34、imilar measurements on specimens fromunknown samples. When unacceptable results are 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 lengthte
35、sts are available from the Cotton Division, Agricultural MarketingService, U.S. Department 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 th
36、e uniformity of the material. See PracticeD 3025.NOTE 4The Fibrograph length results 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
37、 the laboratory controlsamples for the instrument being used.8.3.4 Make additional 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
38、the laboratorysample from the prevailing atmosphere to moisture equilibriumfor testing in the standard atmosphere for testing textilesaccording to Practice D 1776. Preconditioning is not necessary.10. Preparation of Specimens10.1 Fibrosampler Method (Fig. 2):10.1.1 From a sample of fibers, select a
39、subsample ofapproximately 25 grams or more (two handfuls). Place it in the3Instruments and accessories meeting these requirements may be obtained fromUster Technologies, Inc., 456 Troy Circle, P. O. Box 51270, Knoxville, TN37919-1270.D14470713Fibrosampler cylinder. Insert the comb into the Fibrosamp
40、lercombholder. With a circular motion of the left hand, press thefibers so they protrude 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 t
41、he comb.Take the loaded comb from the Fibrosampler, turn the samplearound to present 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
42、 cottonthat has built up on the card cloth contaminate the new sampleand possibly 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 co
43、ndition(see 8.3) and the correct sampling procedure has been estab-lished, insert 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 withou
44、t disturbingtheir distribution in the teeth of the comb(s), and thus completepreparation 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 th
45、e optics to measure thesample.11.3 Test either two or four specimens from each subsamplein 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 mi
46、llimetresdirectly from the LED display of the Fibrograph.11.5 Read the uniformity 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 percentdi
47、rectly from the LED display on the Fibrograph.12. Report12.1 State that the specimens 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
48、as upper-half-mean length (UHML),mean length (ML), uniformity index (ML/UHML) and 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 ofcott
49、on waste.13. Precision and Bias13.1 The precision of this test method is based on 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
