1、Designation: D3412 07D3412/D3412M 13Standard Test Method forCoefficient of Friction, Yarn to Yarn1This standard is issued under the fixed designation D3412;D3412/D3412M; the number immediately following the designation indicatesthe year of original adoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the measurement of frictional properties for both continuous filament and spun-staple yarns und
3、erboundary friction conditions.1.2 This test method has been used with yarns having linear densities ranging from 1.5 to 200400 tex, but may be used withyarns outside these ranges (1515 to 1800 denier).3600 denier.NOTE 1For coefficient of friction, yarn to metal, see Test Method D3108D3108/D3108M.1.
4、3 The values stated in either SI units or inch-pound units are to be regarded separately as the standard. The inch-pound unitsgiven in parentheses are for information only.values stated in each system may not be exact equivalents; therefore, each systemshall be used independently of the other. Combi
5、ning values from the two systems may result in non-conformance with the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and de
6、termine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD1907 Test Method for Linear Density of Yarn (Yarn Number) by the Skein MethodD2258 Practice for Samplin
7、g Yarn for TestingD3108D3108/D3108M Test Method for Coefficient of Friction, Yarn to Solid MaterialD4849 Terminology Related to Yarns and Fibers3. Terminology3.1 For all terminology relating to D13.58, Yarns and Fibers, refer to Terminology D4849.3.2 For all other terminology related to textiles, re
8、fer to Terminology D123.4. Summary of Test Method4.1 A length of yarn is moved at a known speed in contact with itself or similar yarn at a specified wrap angle. The input andoutput tensions are measured and the coefficient of friction calculated. Alternatively, apparatus may be used in which the ra
9、tio ofinput to output tension is measured allowing the coefficient of friction to be indicated directly.4.2 TwoThree optional procedures are included. Option 1 is based on the Twisted Strand Method, using a wrap angle of 15.71rad (900).900. Option 2 is based on the Capstan Method, using a wrap angle
10、 of 3.14 radians (180).180. Option 3 is basedon the Fixed Yarn-Body Capstan Method, using a wrap angle of 3.14 radians 180.NOTE 2Editions of Test Method D3412D3412/D3412M prior to the 1986 revision incorrectly stated the wrap angle for Option 1 to be 18.85 rad. Thisis incorrect, since 3 turns of the
11、 swivel pulley do not result in a wrap angle of 18.85 radians. This has now been corrected to 15.71 rad. This should betaken into account in comparing with earlier results.1 This test method is under the jurisdiction of ASTM Committee D13 on Textiles and is the direct responsibility of Subcommittee
12、D13.58 on Yarns and Fibers.Current edition approved Jan. 1, 2007July 1, 2013. Published January 2007August 2013. Originally approved in 1975T. Last previous edition approved in 20012007 asD3412 01.D3412 07. DOI: 10.1520/D3412-07.10.1520/D3412_D3412M-13.2 For referencedASTM standards, visit theASTM w
13、ebsite, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indica
14、tion of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be con
15、sidered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Significance and Use5.1 This test method for testing yarn-to-yarn friction is being used, but is not recommended, for acceptance testing ofcommercial shi
16、pments since between-laboratory precision is known to be poor.5.1.1 In some cases, the purchaser and supplier may have to test a commercial shipment of one or more specific materials bythe best available method even though the method has not been recommended for acceptance testing of commercial ship
17、ments.In case of a dispute arising from differences in reported test results when using Test Method D3412D3412/D3412M for acceptancetesting of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is astatistical bias between their laboratories.
18、Competent statistical assistance is recommended for the investigation of bias. As aminimum, the two parties should take a group of test specimens that are as homogeneous as possible and that are from a lot ofmaterial of the type in question. The test specimens should then be randomly assigned in equ
19、al numbers to each laboratory fortesting.The average results from the two laboratories should be compared using Students t-test for unpaired data and an acceptableprobability level chosen by the two parties before the testing is begun. If a bias is found, either its cause must be found andcorrected
20、or the purchaser and the supplier must agree to interpret future test results with consideration to the known bias.5.2 This test method is intended for the determination of yarn-to-yarn boundary friction coefficients measured over a specifiedlength of yarn.5.3 The test method is useful for quality c
21、ontrol, research, and the characterization of yarn boundary lubricants.NOTE 3Because the geometry of the yarns is different, Options 1 and 2 should not be expected to give the same numerical values on the same yarns.6. Apparatus6.1 Option 1 (Twisted Strand Method)A schematic diagram of the elements
22、required for twisted strand friction measurementis shown in Fig. 1. The yarn is run over upper pulleys and under a lower pulley and is intertwisted between these pulleys. Oneend of the yarn (output) is taken up at a controlled rate. The other end of yarn (input) is maintained at a controlled tension
23、. Thenumber of intertwisting wraps, the apex angle between the input and output yarns, and the input and output tensions are preciselyknown or recorded. From these data the coefficient of yarn-on-yarn friction is calculated. The required elements are:6.1.1 Friction Testing Apparatus (Indirect)3Appar
24、atus in which the input tension is measured, or controlled to a set value, theoutput tension is measured, and the coefficient of friction is calculated within or outside the apparatus.6.1.1.1 Yarn Input Tension ControlAmeans of controlling the yarn input tension to the nearest 5 % is required.Ademan
25、d-feedapparatus tensioned with a fixed weight is suitable.6.1.1.2 Yarn Input Tension MeasurementThe yarn input tension is measured to within 65.061.0 mN (60.5 gf),60.1 gf,using a suitable tension gagegauge producing an electrical signal. The signal is recorded as millinewtons (grams-force)grams-forc
26、e, or is used in combination with the yarn output tension measured to calculate the coefficient of friction. If a demand-feedapparatus tensioned with a precise, known fixed mass is used, the yarn input tension need not be constantly measured and recorded.6.1.1.3 Yarn Output Tension MeasurementYarn o
27、utput tension is measured to within65.061.0 mN (60.5 gf),60.1 gf, usinga suitable tension gagegauge producing an electrical signal. The signal is recorded as millinewtons, (grams-force),millinewtonsgrams-force, or is used in combination with the yarn input tension setting or measurement to calculate
28、 the coefficient of friction.3 Equipment meeting these requirements may be obtained commercially from: Custom Scientific Instruments Inc, 13 Wing Drive, Cedar Knolls, NJ 07292, andRothschild-Messinstruments, Traubstr 3, 8002 Zurich, Switzerland, represented in the U.S. by Lawson Hemphill Sales Inc,
29、PO Drawer 6388, Spartanburg, SC 29304.FIG. 1 Twisted Strand Yarn-to-Yarn Friction ApparatusTwisted-Yarn MethodD3412/D3412M 1326.1.2 Friction Testing Apparatus (Direct)4Apparatus in which the ratio of output to input tensions are compared directly andthe coefficient of friction is indicated on a scal
30、e.6.1.3 Auxilliary Equipment (Indirect and Direct):6.1.3.1 Guide Pulley ArrangementThe upper and lower pulleys shallsshall be of the same diameter. The recommended pulleydiameter is 38 mm (1.5 in.). ranges between 20 and 50 mm 0.8 and 2 in. The separation distance between the upper pulleys,2 H, shal
31、l be 140 6 25 mm (5.55.5 6 0.1 in.).0.25 in. The separation distance between the axis of the lower pulley and a lineconnecting the upper pulley axes, V, shall be 280 6 25 mm (1111 6 0.1 in.).0.25 in. All pulleys shall be in the same plane. Thelower pulley may optionally be mounted so that it can be
32、swiveled around an axis at right angles to its axis of rotation and thenfixed in position in the same plane as the upper pulleys.6.1.3.2 Drive UnitThe yarn takeup shall run between 200.1 and 100200 mm/min (0.750.004 and 4.0 in./min).8 in./min.6.2 Option 2 (Capstan Method)A schematic diagram of the e
33、lements required for the Capstan Method is shown in Fig. 2.Suitable elements are:6.2.1 CylinderA rotating mandrel of 50 6 2 mm (2.02.0 6 0.1 in.)in. outside diameter.6.2.2 Drive UnitA mechanism designed to rotate the cylinder at a surface speed of 20 6 1 mm/min (0.750.75 6 0.04in./mm).in./mm.6.2.3 W
34、inding UnitA device to wrap the yarn on the surface of the cylinder. A helix angle of 0.2 to 0.3 rad (1010 to 15)15is needed to prevent burrowing by the hanging strand of yarn.6.2.4 Tension GageGaugeA suitable tension gage,gauge, producing an electrical signal, to measure the yarn output tensionwhic
35、h is recorded as millinewtons or after calculation as coefficient of friction.6.2.5 WeightsA set of weights or other device to preset the input tension.NOTE 4Measured stick-slip differentials are greatly dependent on tension transducer spring constants, yarn modulus, and recorder frequencyresponses.
36、 If interlaboratory checks are required, the same type of tension transducer and recorder should be used and the distance between the transducerand the hanging weight to center line of the mandrel must be specified.6.3 Option 3 (Fixed Yarn-Body Capstan Method)A schematic diagram of the elements requ
37、ired for the Fixed Yarn BodyMethod is shown in Fig. 3. Suitable elements are:6.3.1 Friction Testing ApparatusApparatus in which the input tension is measured, or controlled to a set value, the outputtension is measured, and the coefficient of friction is calculated within or outside the apparatus.6.
38、3.1.1 Yarn Input Tension MeasurementThe yarn input tension is measured to within 61.0 mN 60.1 gf, using a suitabletension gauge producing an electrical signal. The signal is recorded as millinewtons or centinewtons (grams-force), or is used incombination with the yarn output tension measured to calc
39、ulate the coefficient of friction. If a demand-feed apparatus tensionedwith a precise, known fixed mass is used, the yarn input tension need not be constantly measured and recorded.6.3.1.2 Yarn Output Tension MeasurementYarn output tension is measured to within 61.0 mN 60.1 gf, using a suitabletensi
40、on gauge producing an electrical signal. The signal is recorded as millinewtons or centinewtons, (grams-force), or is used incombination with the yarn input tension setting or measurement to calculate the coefficient of friction.6.3.2 Drive UnitThe yarn takeup shall run between 0.1 and 200 mm/min 0.
41、0039 and 7.9 in./min.6.3.3 CylinderA fixed mandrel capable of fixing a bobbin of 50 6 5 mm 2.0 6 0.25 in. outside diameter.4 Equipment meeting these requirements may be obtained commercially from: Rothschild-Messinstruments, Traubstr 3, 8002 Zurich, Switzerland, represented in the U.S.by Lawson Hemp
42、hill Sales Inc, PO Drawer 6388, Spartanburg, SC 29304, and Shirley Developments Ltd, PO Box 6, Didsbury, Manchester M20 8SA, England, representedin the U.S. by Lawson Hemphill Sales Inc, PO Drawer 6388, Spartanburg, SC 29304.FIG. 2 Yarn-to-Yarn Friction ApparatusCapstan MethodD3412/D3412M 1336.3.4 W
43、eightsA set of weights or other device to preset the input tension.7. Sampling7.1 Lot SampleAs a lot sample for acceptance testing, take at random the number of shipping containers directed in anapplicable material specification or other agreement between the purchaser and the supplier, such as an a
44、greement to use PracticeD2258. Consider shipping containers to be the primary sampling units.NOTE 5An adequate specification or other agreement between the purchaser and the supplier requires taking into account the variability betweenshipping units, between packages or ends within a shipping unit,
45、and between specimens from a single package so as to provide a sampling plan witha meaningful producers risk, consumers risk, acceptable quality level, and limiting quality level.7.2 Laboratory SampleAs a laboratory sample for acceptance testing, take at random from each shipping unit in the lot sam
46、plethe number of packages or ends directed in an applicable material specification or other agreement between the purchaser and thesupplier such as an agreement to use Practice D2258. Preferably, the same number of packages should be taken from each shippingunit in the lot sample. If differing numbe
47、rs of packages are to be taken from shipping units in the lot sample, determine at randomwhich shipping units are to have each number of packages drawn.7.3 Test SpecimensTest one specimen from each package in the laboratory sample.8. Conditioning8.1 Preparation of Test PackagesRemove sufficient yarn
48、 from the test packages to avoid testing non-representative layers. Ifin doubt, remove about 10 % of the length of yarn on the package.8.2 The strand to be tested must have a uniform moisture content along its length. Atmospheric conditions must therefore bestable and the strand must be in equilibri
49、um with the prevailing atmosphere. To satisfy this condition, testing should be carried outafter thorough conditioning in the standard atmosphere for testing textiles.8.3 PreconditioningPrecondition packages of yarn for at least 3 h in an atmosphere with a relative humidity between 5 and25 % and a temperature not exceeding 50C (121F).8.3 ConditioningCondition the preconditioned packages of yarn in the standard atmosphere for testing textiles (relativehumidity 65 6 2 % and temperature 21 6
