1、Designation: D 645/D 645M 97 (Reapproved 2002)An American National StandardStandard Test Method forThickness of Paper and Paperboard1This standard is issued under the fixed designation D 645/D 645M; the number immediately following the designation indicates the yearof original adoption or, in the ca
2、se of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the thick-ness of paper and paperboard excep
3、t electrical insulatingpapers (see Test Methods D 202).1.1.1 Because of the relatively high pressure 50 kPa 7.3psi used in this test method, it may not be suitable formeasurement of tissue or other soft or low density materials,because the structure may collapse (decrease in thickness) atthe prescri
4、bed pressure of 50 kPa.1.2 The values stated in either SI units or in other units shallbe regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each systemmust be used independently of the other, without combiningvalues in any way.1.3 This standard
5、 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 to use.2. Referenced Documents2.1 ASTM
6、Standards:D 202 Test Methods of Sampling and Testing UntreatedPaper Used for Electrical Insulation2D 585 Practice for Sampling and Accepting a Single Lot ofPaper, Paperboard, Fiberboard, and Related Product3D 685 Practice for Conditioning Paper and Paper Productsfor Testing3D 1968 Terminology Relati
7、ng to Paper and Paper Products32.2 TAPPI Standards:T 411 Thickness (caliper) of paper, paperboard, and combi-nation board4T 1206 Precision statements for test methods43. Terminology3.1 Definitions shall be in accordance with TerminologyD 1968 and the Dictionary of Paper.44. Significance and Use4.1 T
8、hickness is an important property of paper or paper-board, critical for certain end uses of paper and paperboard.This test method is useful for research work, routine control,design of end-use products, and for acceptance testing forconformance to a specification. Apparent density and otherpaper pro
9、perties are related to thickness.5. Apparatus5.1 Micrometer, conforming to the following specifications:5.1.1 Motor operated, dead-weight (not spring) actuated.5.1.2 The micrometer shall have a flat ground circularmovable face (the presser foot), having an area of 200 6 5mm2equivalent to about 0.31
10、6 0.01 in.2 and correspondingto a diameter of 16 6 0.2 mm 0.63 6 0.01 in.5.1.3 The micrometer shall have a flat ground circular fixedface (the anvil) of such size that it is in contact with the wholearea of the pressure foot in the zero position.5.1.4 The surface of the presser foot shall be paralle
11、l to thesurface of the anvil to within 0.001 mm 0.00005 in. Thepresser foot movement shall be on an axis that is perpendicularto the anvil surface. The minimum distance between the anviland the presser foot in the “up” or raised position shall be 0.75mm 0.030 in.5.1.5 The presser foot, when lowered,
12、 shall exert steadypressure on the specimen of 50 6 2 kPa approximately 7.3 60.3 psi or 0.51 kgf/cm2 for 3 6 1 s. The period of steadypressure on the specimen is referred to as dwell time.5.1.6 The presser foot shall have a lowering speed of 0.8 60.1 mm 0.03 6 0.004 in./s.5.1.7 The frame of the micr
13、ometer shall be of such rigiditythat a load of 1.5 kg (3 lb) applied to the dial housing, out ofcontact with either the weight or the presser foot spindle, willproduce a deflection of the frame not greater than 0.0025 mm0.0001 in. as indicated by the micrometer readout system.5.2 Readout SystemTwo t
14、ypes of readout systems areavailable for use in this test method as follows:5.2.1 Dial-Type System with a dial, graduated to 0.002 mm0.0001 in. or less, readable to at least 0.001 mm 0.00005 in.,1This test method is under the jurisdiction of ASTM Committee D06 on Paperand Paper Products and is the d
15、irect responsibility of Subcommittee D06.92 on TestMethods.Current edition approved Dec. 10, 1997. Published November 1998. Originallyapproved in 1941. Last previous edition approved in 1996 as D 645 96.2Annual Book of ASTM Standards, Vol 10.01.3Annual Book of ASTM Standards, Vol 15.09.4Available fr
16、om the Technical Association of the Pulp and Paper Industry,Technology Park, P.O. Box 105113, Atlanta, GA 30348.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.or 1 % of paper thickness, whichever is larger. If the largeindicating ha
17、nd of the dial is required to revolve more thanonce to cover the capacity of the gage, equip the dial with arevolution counter to indicate the number of complete revolu-tions of the indicating hand.5.2.2 Digital-Type Readout System, with a digital displayindication to at least 0.001 mm 0.00005 in.,
18、or 1 % of paperthickness, whichever is larger.5.2.3 The readout system used shall be capable of repeatingreadings to within 0.001 mm 0.00005 in. at zero settings oron a steel gage block.6. Test Specimens6.1 Obtain specimens from samples obtained in accordancewith Practice D 585.NOTE 1Some paper manu
19、facturers and users measure the thickness ofpapers 0.051 mm and under using a specimen that contains eight or tensheets of paper. Usually, but not always, if a micrometer is used tomeasure the thickness of a single sheet of this thinness, the error in readingthe instrument is likely to make a signif
20、icant difference in the result. If apile of 10 sheets is measured and the result divided by 10, there will alsobe an error due to the “piling effect,” but the latter error will, in general,be smaller than the former. In existing specification documents the valuesfor thickness of thin papers 0.051 mm
21、 or less may require modificationif this single sheet method is referenced in that material specificationdocument.7. Calibration7.1 Measurements are made on standard steel gages with thethickness known within 0.0008 mm 0.00003 in. The mea-surements shall be within the following tolerances:IntervalsP
22、ermissible Deviation of Reading from ActualThickness of Standard Steel Gage0 to 0.25 mm 0.01 in. 6 0.0012 mm 0.00005 in.Over 0.25 mm 0.01 in. 6 0.005 mm 0.0002 in.NOTE 2In the use of steel gages made of a nondeformable material,it must be remembered that the value corresponding to the thickest porti
23、onof the gage, rather than the average thickness, should be used in thecalibration of paper micrometers.7.1.1 Apply the deviations for the parts of the scale corre-sponding to the specimen thickness measured as corrections tothe thickness reading.7.2 Parallelism of the FacesUse a uniform diameter wi
24、reof any size up to half the operational opening of the faces (forexample, 0.5 mm 0.020 in. diameter). Alternate the wire onthe left side, right side, front side, and back side approximately3mm18 in. from each respective edge of the foot. Note thereadings. Adjust the anvil so that all readings are w
25、ithin 0.001mm 0.00005 in. of one another.NOTE 3An acceptable alternative to the thin wire described above isa hard steel ball, 1 mm or less in diameter, fixed in a thin (less than 1 mmin thickness) flat piece of metal, or else the tip of a feeler gage of aboutthe same thickness specified for the wir
26、e. Use any of the three devices asdescribed in 7.2.7.3 The frame of the micrometer shall be of such rigiditythat a load of 1.5 kg (3 lb) applied to the dial housing, out ofcontact with either the weight or the presser foot spindle, willproduce a deflection of the frame not greater than 0.0025 mm(0.0
27、001 in.), as indicated by the micrometer readout system.8. Conditioning8.1 Condition all specimens in accordance with PracticeD 685 prior to testing for thickness. Conduct all tests forthickness in a room or chamber in which the atmosphericconditions of Practice D 685 are maintained.9. Procedure9.1
28、GeneralBefore using any micrometer, make sure thatthe presser foot and anvil surfaces are clean, that the calibrationof the instrument has been verified and a calibration curve hasbeen prepared, if necessary, and that the instrument is mountedon a solid level surface free from noticeable vibration.9
29、.2 Place the specimen on the anvil in such a position thatall points on the peripheries of the contact surface are at least6 mm (0.25 in.) from the edges of the specimen.9.2.1 When using multiple-sheet test specimens includingcombined paperboard, the presser foot shall not be closer than20 mm (0.75
30、in.) from any edge of the stack.9.3 Take a specified number of measurements mutuallyagreed upon between the producer and the consumer. Measureat regular intervals across the entire width of each specimen,preferably in a line that is at right angles to the machinedirection of the paper. In all cases,
31、 make at least five suchmeasurements on each specimen, except if only an estimate oflot or test unit average is required (that is, variations ofthickness within a sheet are of no interest). Then only tworeadings per specimen need be made.9.4 Take each reading near the end of the dwell time. Ifnecess
32、ary, apply the calibration corrections to the readings.9.5 If the thickness of noticeably compressible papers isbeing measured, it is particularly important that the rate of fallof the presser foot and the dwell time be within the specifiedlimits. (See 5.1.5 and 5.1.6.) Examples of noticeably compre
33、ss-ible papers include tissue paper, or other soft or low-densitypapers.10. Report10.1 Report the following information:10.1.1 The corrected values of average, maximum, andminimum thickness obtained on each test specimen, exceptwhere, by agreement between producer and consumer, onlytwo tests per spe
34、cimen have been made. Then only the averageneed be reported.10.1.2 The method used.10.1.3 The number of readings taken on each specimen.10.2 Thickness may be expressed in any applicable units ofdistance such as millimetres, inches, mils, etc., as agreed uponby producer and consumer.11. Precision and
35、 Bias11.1 Precision:11.1.1 Repeatability1.25 %.11.1.2 Reproducibility5.50 %.11.1.3 The above precision was calculated from data takenfrom 24 reports of the Collaborative Reference Program forPaper,4using procedures for calculation as specified in TAPPIT 1206.11.1.4 The user of this precision data is
36、 advised that it isbased on actual mill testing, laboratory testing, or both. ThereD 645/D 645M 97 (2002)2is no knowledge as to the exact degree to which personnelskills or equipment were optimized during its generation. Theprecision provides an estimate of typical variation in testresults which may
37、 be encountered when this test method isused by two or more parties.11.2 BiasThe procedure in this test method has no biasbecause the value of thickness is defined only in terms of thetesting conditions specified in this method.12. Keywords12.1 caliper paper; paperboard; thicknessAPPENDIXES(Nonmanda
38、tory Information)X1. MANUALLY OPERATED MICROMETERX1.1 The manually operated micrometer does not conformto this test method. This Appendix simply gives generalinformation on use of such a micrometer, as many are still inuse.X1.2 Apparatus:X1.2.1 Dial-Type MicrometerManually-operated, dead-weight actu
39、ated, conforming in general to the requirements forthe motor-operated instrument.X1.3 Procedure:X1.3.1 Place the specimen between the contact surfaces andlower the pressure foot onto the specimen at a location outsideof the area to be measured. Note this trial reading. Raise thepressure foot, move t
40、he specimen to the measurement position,lower the pressure foot to within 0.008 mm 0.0003 in. of thesurface of the specimen (that is, to the previous reading plus0.008 mm) and then release the pressure foot.X1.3.2 For each succeeding measurement, raise the pressurefoot, move the specimen to the next
41、 measurement location, andlower the pressure foot to within 0.008 mm 0.0003 in. of thesurface of the specimen (as defined by the previous reading)before releasing the pressure foot.X1.3.3 As an alternative technique, recommended when thevariations in specimen thickness are greater than 0.008 mm,lowe
42、r the pressure foot at some velocity less than 12 mm 0.5in./s onto the surface of the paper specimen.X1.3.4 Repeat, making five readings per specimen, exclud-ing the trial reading.X1.4 Precision and Accuracy:X1.4.1 Because of the greater influence of the operator, themanually-operated instrument has
43、 shown less agreementamong laboratories than the motorized instrument. Properlyand skillfully operated, the accuracy of the manually operatedinstrument should be as good as that of the motorized instru-ment except possibly on highly compressible papers for whichdifferences of 3 % have been reported.
44、X2. DIFFERENCES BETWEEN ISO 534 AND TEST METHOD D 645X2.1 Both the ASTM and TAPPI (T411) test methodsspecify a pressure between the foot and the anvil of themicrometer of 50 6 2 kPa. ISO 534 specifies the pressure of100 6 10 kPa as the “preferred” and 506 5 kPa as an“alternative.” An instrument conf
45、orming with the ISO standardof 100 kPa is likely to give lower values than an instrumentconforming to the ASTM standard, with the difference afunction of compressibility of the paper.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any ite
46、m mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical comm
47、ittee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a m
48、eeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive
49、, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 645/D 645M 97 (2002)3
