1、Designation: D7241 13Standard Test Method forPile Thickness of Finished Multilevel Pile Yarn FloorCovering1This standard is issued under the fixed designation D7241; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of pilethickness of finished multilevel pile yarn floor covering usinga thickness
3、 measuring instrument having a stationary surface(platen), a circular pressure foot under specified force, andcapable of being moved vertically above the platen.1.2 This test method is applicable only to finished multilevelloop pile constructions.NOTE 1Determination of pile thickness of multilevel p
4、ile yarn floorcoverings was previously contained within Test Method D418. For userconvenience, Subcommittee D13.21 subdivided Test Method D418 intoseparate standards of which this test method is one.1.3 The values stated in inch-pound units are to be regardedas standard. The values given in parenthe
5、ses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.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 s
6、afety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD5684 Terminology Relating to Pile Floor CoveringsD5823 Test Method f
7、or Tuft Height of Pile Floor CoveringsE122 Practice for Calculating Sample Size to Estimate, WithSpecified Precision, the Average for a Characteristic of aLot or Process3. Terminology3.1 For definitions of terms relating to Pile Floor Coverings,refer to the Terminology D5684.3.2 The following terms
8、are relevant to this standard: carpet,cut pile yarn floor covering, finished, finished pile yarn floorcovering, floor covering, pile, pile thickness, pile yarn floorcovering, pitch, primary backing, shorn pile stubble, stubbleheight, textile floor covering, tufted fabric.3.3 For definitions of other
9、 terms related to textiles, refer toTerminology D123.3.4 For discussion of terminology specific to this standard,see Annex A1.4. Summary of Test Method4.1 The thickness and mass are measured on each selectedstrip specimen in the unsheared condition and after removingapproximately 25, 50, 75 % and al
10、l of the pile down to astubble by shearing. The net pile thicknesses at the 25, 50, and75 % levels are calculated by subtracting the stubble specimenthickness from the thicknesses measured at each of the otherstages. The net pile masses are calculated by subtracting themass of the stubble specimen f
11、rom the four other weighings.The 25, 50, and 75 % net masses are expressed as a percent ofthe net pile mass of the unsheared specimen and the 25, 50, and75 % net thicknesses are plotted against these net masspercentages.Asmooth curve is drawn through the three plottedpoints. The net pile thickness c
12、orresponding to 50 % net massis read from the smooth curve and doubled to obtain theaverage pile thickness.5. Significance and Use5.1 The determination of pile thickness of multilevel pileyarn floor covering is useful in quality and cost control duringmanufacture of pile yarn floor covering. The app
13、earance andperformance may be affected by changes in pile thickness ofpile yarn floor coverings. This test method is consideredsatisfactory for acceptance testing of commercial shipmentsbecause current estimates of between laboratory precision areacceptable, and this test method is commonly used in
14、the tradefor acceptance testing.1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.21 on Pile Floor Coverings.Current edition approved July 1, 2013. Published September 2013. Originallyapproved in 2006. Last previous edit
15、ion approved in 2006 as D7241-06. DOI:10.1520/D7241-13.2For 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.Copyri
16、ght ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.2 If there are differences of practical significance betweenreported test results for two laboratories (or more), compara-tive tests should be performed to determine if there is astatistical
17、 bias between them, using competent statistical assis-tance. As a minimum, use the samples for such comparativetests that are as homogenous as possible, drawn from the samelot of material as the samples that resulted in disparate resultsduring initial testing and randomly assigned in equal numbersto
18、 each laboratory. The test results from the laboratoriesinvolved should be compared using a statistical test forunpaired data, a probability level chosen prior to the testingseries. If a bias is found either its cause must be found andcorrected, or future test results for that material must beadjust
19、ed in consideration of the known bias.6. Sampling, Test Specimens, and Test Units6.1 Sampling Units:6.1.1 Coated Floor CoveringThe basic sampling unit ofcoated floor covering is a shipping roll. The number ofshipping rolls obtained from each production roll ranges fromone to over ten.6.1.2 Lot Sampl
20、eTake a lot sample as directed in PracticeE122 when statistical knowledge of the product variability andtest method precision is available, and a decision has beenmade on the maximum deviation that can be tolerated betweenthe estimate to be made from the sample and the result thatwould be obtained b
21、y measuring every sampling unit of the lot.Otherwise the number of sampling units in a lot sample and theuse of the test results obtained from the individual test samplesshall be in accordance with the manufacturers quality controlprogram or with the specification agreed upon between thepurchaser an
22、d the supplier.6.1.3 Laboratory Sampling UnitA laboratory samplingunit shall consist of a full width section of floor covering cutfrom one end of each roll in the lot sample and shall be at least4 in. (100 mm) longer than the specimens required for the testsbeing conducted. Do not cut a laboratory s
23、ampling unit ofcoated floor covering from a seam end of a production roll.6.1.4 Test SpecimensA test specimen is a designated areacut from a laboratory sampling unit For laboratory samplingunits 120 in. (3000 mm) wide or wider, three test specimens arerequired for a test method, one at each edge no
24、nearer to theedge than 5 % of the total floor covering width and one in themiddle portion of the test sample. For laboratory samplingunits at least 60 in. (1500 mm) wide but less than 120 in. (3000mm), take two test specimens, one at each edge no nearer to theedge than 5 % of the total floor coverin
25、g width. For laboratorysampling units less than 120 in. (1500 mm) wide, take one testspecimen from the middle.6.2 Where it is known that systematic variations in a floorcovering characteristic may occur in bands 18 in. (460 mm) ormore in width, as with a modular pattern device havingseparate control
26、s or adjustments for each module, take testspecimens from the middle of each band.6.3 When a full-width sample is not available, take speci-mens as directed in 6.1.4, and state in the report the widthavailable and the number of test specimens taken.7. Apparatus7.1 Balance, capable of weighing to the
27、 nearest 0.01 g.7.2 Shear or Clipper, capable of shearing close enough tothe backing so as to leave a stubble of no more than 0.05 in.(1.3 mm).7.2.1 Means for adjusting the height of the shear, such asshims or mechanical mount for a shearing head.7.3 Thickness Measuring Instrument:7.3.1 Having a sta
28、tionary surface (plate) on which to placethe specimen, and a presser foot capable of being movedvertically above the plate, at least 1 in. (25 mm) from the plate.7.3.2 Having two interchangeable presser feet; one 1.000 60.001 in. (25.4 6 0.03 mm) diameter, the other 2.250 6 0.001in. (57.15 6 0.03 mm
29、) in diameter.7.3.3 Having means for indicating the vertical distancebetween the presser foot and the plate to the nearest 0.001 in.(0.03 mm) and capable of developing and indicating a force upto 0.6 lbf (2.77 N) between the presser foot and the plate.7.4 Graph Paper, with 0.1-in. (2-mm) divisions.7
30、.5 Drafting Curves, such as a set of French curves, flexiblecurve, or software capable of drawing the graph.8. Preparation of Apparatus8.1 Attach the presser foot loosely to the moveable stem orhead of the instrument and bring the presser foot into firmcontact with the plate. Tighten the presser foo
31、t on the stem,check the instrument zero by lowering the presser foot intocontact with the plate until the indicated pressure increases tothe pressure to be used in measuring the distance between thefoot and the plate. The instrument must read 0 6 0.001 in. (06 0.03 mm), if the reading is not within
32、this range a adjustmentshall be made appropriate to the type of instrument being used.Verify the instrument with calibrated thickness blocks.9. Conditioning9.1 Condition the laboratory sampling unit or the testspecimens in the standard atmosphere for testing textiles, thatis 70 6 2F (21 6 1C) at 65
33、6 2 % relative humidity, 12 h oruntil the mass changes no more than 0.1 % in2hasdirectedin Practice D1776.10. Procedure10.1 Select the number and location of the test specimens asdirected in Section 6. Prepare the test specimens according tothe procedure in Annex A2.10.2 The test specimens shall com
34、prise a full pattern repeator a whole number multiple of a full pattern repeat in eachdirection but no less than 9.9 6 0.1 in. (250 6 3 mm) in thelengthwise direction by 12.5 6 0.1 in. (320 6 3 mm) in thewidthwise direction. If the pattern repeat is not known andcannot be determined readily, use 18.
35、0 by 18.0 6 0.1 in. (457by 457 6 3 mm) for the test specimen dimensions.10.3 Select a strip specimen from each of the test speci-mens. The strip specimens shall be 9.9 6 0.1 in. (250 6 3 mm)D7241 132in the lengthwise direction and 2.5 6 0.1 in. (64 6 3 mm) inthe widthwise direction and should be con
36、ditioned as directedin Section 9.10.3.1 Determine the total mass of all the strip specimens tothe nearest 0.01 g and record as Mo, where the subscript zeroindicates the strip specimens are unsheared.10.4 Total Thickness:10.4.1 Attach the 2.250 in. (57.15 mm) presser foot asdirected in 8.1. For each
37、strip specimen, raise the presser footand center the specimen, pile face up, on the plate under thefoot. Lower the presser foot slowly (take about5stoapply fullload) onto the pile surface until a pressure of 0.100 6 0.003 psi(689 6 21 Pa) is exerted on the specimen. Read the distancebetween the pres
38、ser foot and the plate to the nearest 0.001 in.(0.03 mm). Determine the total thickness in three differentareas for each strip specimen and record the average as the totalthickness, To.10.5 Estimation of Shearing Levels:10.5.1 Obtain an approximate stubble specimen thicknessby shearing the pile down
39、 to a stubble measuring approxi-mately 0.05 in. (1.3 mm).10.5.2 Attach the 1.000 in. (25.40 mm) diameter presserfoot loosely to the stem and bring the presser foot into firmcontact with the plate. Tighten the presser foot on the stem.Check the instrument zero as directed in 8.1. Verify theinstrument
40、 with calibrated thickness blocks.10.5.3 For each stubble specimen, raise the presser foot andcenter the specimen, stubble side up, on the plate. Lower thepresser foot onto the stubble surface until a pressure of 0.75 60.01 psi (5170 6 69 Pa) is exerted on the stubble specimen.Read the distance betw
41、een the presser foot and the plate to thenearest 0.01 in. (0.03 mm). Determine the stubble thickness inthree different areas of the strip specimen and record theaverage as the stubble thickness h.10.5.4 Obtain an approximate total pile thickness using Eq1:Z 5 To2 h (1)where:Z = total pile thickness,
42、 in. (mm),To= average total thickness, in. (mm), andh = average stubble thickness, in. (mm).10.5.5 Calculate target thicknesses to the nearest 0.001 in.(0.03 mm) for removing 25, 50, and 75 % of the pile using Eq2-4:T255 0.75Z1H (2)T505 0.5Z1H (3)T755 0.25Z1H (4)where:T25,T50,T75= target shearing th
43、ickness for 25, 50, and75 % shearing, in. (mm),Z = total thickness, To h, in. (mm) andh = stubble thickness, approximate thickness ofbacking material plus stubble, in. (mm).10.6 25 % Shearing:10.6.1 Shear each strip specimen to a thickness of approxi-mately t25. Remove all loose fibers from the spec
44、imens.10.6.2 Attach the 2.250 in. (57.15 mm) presser foot looselyto the moveable stem of the instrument and bring the presserfoot into firm contact with the plate. Tighten the presser foot onthe stem. Check the instrument zero as directed in 8.1. Verifythe instrument with calibrated thickness blocks
45、.10.6.3 Measure the 25 % sheared strip specimen thicknessat three different locations, average the measurements for allstrip specimens and record the average as T1, to the nearest0.001 in. (0.03 mm).10.6.4 Determine the total mass of all the 25 % sheared stripspecimens and record to the nearest 0.01
46、 g as M1.10.7 50 % Shearing:10.7.1 Shear each strip specimen to a thickness of approxi-mately t50. Remove all loose fibers from the specimens.Measure the 50 % sheared strip specimen thickness at threedifferent locations, average the measurements for all stripspecimens and record the average as T2, t
47、o the nearest 0.001 in.(0.03 mm).10.7.2 Determine the total mass of all the 50 % sheared stripspecimens and record to the nearest 0.01 g as M2.10.8 75 % Shearing:10.8.1 Shear each strip specimen to a thickness of approxi-mately T75. Remove all loose fibers from the specimens.Measure the 75 % sheared
48、 strip specimen thickness at threedifferent locations, average the measurements for all stripspecimens and record the average as T3, to the nearest 0.001 in.(0.03 mm).10.8.2 Determine the total mass of all the 75 % sheared stripspecimens and record to the nearest 0.01 g as M3.10.9 Stubble Shearing:1
49、0.9.1 Shear each strip specimen as close to the back aspossible (approximately 0.05 in. (1.3 mm). Remove all loosefibers from the specimens.10.9.2 Attach the 1.000 in. (25.40 mm) diameter presserfoot loosely to the stem and bring the presser foot into firmcontact with the plate. Tighten the presser foot on the stem.Check the instrument as directed in 8.1.10.9.3 Measure the stubble specimen thickness at threedifferent locations, average the measurement for all stripspecimens and record the average as T4to the nearest 0.001 in.(0.03 mm).10.9.4 Determine the total mass of all t
