1、Designation: D 3767 03Standard Practice forRubberMeasurement of Dimensions1This standard is issued under the fixed designation D 3767; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parenthes
2、es indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This practice is intended for use in determining thegeometrical dimensio
3、ns of rubber products and specimens forphysical tests. This practice describes procedures for determin-ing length, width, thickness, diameter, and circumference. Thispractice does not cover sampling of materials or products, orlocations where a sample is to be taken.1.2 The values stated in either a
4、cceptable metric units or inother units shall be regarded separately as a standard. Thevalues stated in each system may not be exact equivalents;therefore, each system must be used independently of the other,without combining values in any other way.1.3 This standard does not purport to address all
5、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 or regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1415 Test Method for
6、 Rubber PropertyInternationalHardnessD 3183 Practice for RubberPreparation of Pieces for TestPurposes From Products3. Summary of Practice3.1 Specific procedures are outlined depending upon size,texture, and shape of the test specimens undergoing measure-ment.3.1.1 Procedure A encompasses linear dime
7、nsions up to 30mm using a flat-footed micrometer on flat sheets and testspecimens.3.1.2 Procedure A1 encompasses thickness dimensions upto 30 mm using a micrometer with contact members that aredomed surfaces. This procedure is employed on irregularlyshaped test specimens and compression set test spe
8、cimens.3.1.3 Procedure A2 encompasses thickness measurementsof flexible cellular test specimens up to 30 mm using amicrometer with large area flat contact members.3.1.4 Procedure B encompasses linear dimensions between30 and 100 mm using a vernier caliper.3.1.5 Procedure C encompasses linear dimensi
9、ons above100 mm using a tape or linear scale.3.1.6 Procedure D encompasses thickness measurements onsoft thin materials using a microscope.3.1.7 Procedure E encompasses circumference measure-ments by cone.4. Significance and Use4.1 Dimensional measurements specified in this practice aremade for one
10、of the following purposes: (1) to determineconformance with specification requirements regarding geo-metrical properties of whole units, such as the size of rubbergloves, or the diameter and circumference of rubber hose, (2)to determine conformance with specification requirementsregarding particular
11、 functional parts of units, such as thethickness of the soles of boots, or ( 3) to determine geometricalvalues that are necessary in the calculation of test results forphysical properties for which requirements are specified, suchas the thickness of a test specimen for tensile strength. Themethod to
12、 be used shall be as specified in the detail specifica-tion or appropriate test method.4.2 Pressure applied by measuring instruments has a signifi-cant effect on the observed thickness of soft flexible materials,and it is therefore necessary to specify the pressure imposed bythe foot of the instrume
13、nt on the test piece for accuratecomparative measurements of such materials.5. Test Specimens5.1 Test specimens shall consist of a product, in whole or inpart, for which the geometric dimensions are sought, asdescribed in a detail specification or test method. Material, as1This practice is under the
14、 jurisdiction of ASTM Committee D11 on Rubber andis the direct responsibility of Subcommittee D11.10 on Physical Testing.Current edition approved Dec. 1, 2003. Published January 2004. Originallyapproved in 1979. Last previous edition approved in 2001 as D 3767 01.2For referenced ASTM standards, visi
15、t 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 Harbor Drive, PO Box C700, West Conshohocken, PA 19428-29
16、59, United States.referenced herein, shall be interpreted as the substance(s) ofwhich a product is comprised.6. Number of Measurements6.1 Unless otherwise specified in the detail specification ortest method, three measurements shall be made on each testspecimen or product and the median value taken.
17、7. Buffing7.1 If the test specimen has uneven surfaces, such as fabricimpression or corrugations, that may interfere with the test, forexample, on the tube or cover of hose, the material may bebuffed lightly so that the surface is smooth and of uniformthickness. Buffing shall be performed in accorda
18、nce with thesections on Buffing Techniques, Abrasive Wheels, and Abra-sive Flexible Bands in Practice D 3183.8. Conditioning8.1 Unless otherwise specified in the detail specifications ortest method, geometrical measurements shall be made afterconditioning test specimens for 24 h at 23 6 5C (73.4 6 9
19、F).If Procedure D (see Section 12) is used, the relative humidityof 50 6 5 % at 23 6 2C (73.4 6 3.6F) should be maintained.PROCEDURES9. Procedures A, A1, and A2 (Dimensions of 30 mm orLess)9.1 Procedure A:9.1.1 ScopeDimensions of length, width, thickness, anddiameters of test specimens less than 30
20、mm (1.2 in.) shall bemeasured with a micrometer instrument.9.1.2 ApparatusThe apparatus shall consist of the follow-ing parts (an example of suitable apparatus is shown in Fig. 1NoteProcedure: Lift the yoke to the raised position and place the specimen between the base plate and circular presser foo
21、t. Lower the presser foot and yoke untilthe rod is resting freely on the test specimen, but with the dial-gage stem still supported. Lock the clamp and then lower the yoke fully. Read the micrometer.FIG. 1 Example of a Suitable Measuring Apparatus for Procedure AD3767032and Fig. 2):9.1.2.1 Anvil, at
22、 least 35 mm (1.4 in.) in diameter, that isattached to a rigid base plate.(1) Flat Rigid Base Plate, at least 140 mm (5.5 in.) indiameter, that is attached to a rigid frame.(2) Solid Platform Base (see Fig. 2), granite, at least 5 by 5in. square and 1.75 in. in height. The top surface is ground flat
23、and perpendicular to the guide post and micrometer assembly,at the operating height, to a tolerance of 60.002 in.9.1.2.2 Micrometer (such as a dial or digital-electronic),capable of measuring dimensions to an accuracy within 1 % ofthe dimension being measured or 0.001 mm, whichever isgreater.9.1.2.3
24、 Rigid Rod:(1) terminating in its lower end in a flat circular foot 3 to 10mm (0.12 to 0.39 in.) in diameter (see Fig. 1). The rod designshall allow various masses to be attached in order to give theoperator the capability of varying the pressure exerted on thetest specimen, by the presser foot, fro
25、m 10 to 22 kPa (1.55 to3.2 psi) (refer to Table 1).(2) terminating in its upper and lower ends in a threadedorifice. The lower orifice will accommodate the connection ofa flat circular foot 3 to 10 mm (0.12 to 0.39 in.) in diameter.The upper orifice will accommodate the attachment of a masscorrespon
26、ding to the presser foot attached (refer to Table 1 andFig. 2) in order to give the operator the capability of varyingthe pressure exerted on the test specimen by the presser footfrom 10 to 22 kPa (1.55 to 3.2 psi) (refer to Table 1).9.1.3 Procedure A:9.1.3.1 When using an instrument equivalent to t
27、he oneshown in Fig. 1:Place the test specimen between the base plate and the circularpresser foot. Lower the presser foot until it is resting freely onthe test specimen.Read the micrometer to an accuracy within 1 % of theNoteProcedure: Lower the contact foot so it is resting freely on the platform.
28、Reset the micrometer to zero. Return the contact foot to a raised position. Place the testspecimen on the platform. Lower the contact foot, gently, until it contacts the test specimen. Read the micrometer.FIG. 2 Example of a Suitable Apparatus for Procedure ATABLE 1 Mass/Presser Foot CombinationsMat
29、erials Equal to or Above 35 IRHD:22 6 5 kPa / 3.2 6 0.7 psiFoot (mm)OptimalMass (g)MaximumMass (g)MinimumMass (g)10.0 176 215 1388.0 113 138 886.3 70 85 556.0 63 77 505.0 44 54 344.0 28 34 223.2 18 22 1416.0A452 551 35325.0A1104 1346 863Materials Below 35 IRHD:10 6 2 kPa / 1.5 6 0.3 psiFoot (mm)Opti
30、malMass (g)MaximumMass (g)MinimumMass (g)10.0 80 97 648.0 52 62 416.3 32 38 256.0 29 35 235.0 20 24 164.0 13 15 103.2 8 10 616.0A212 254 17025.0A518 621 414AThe 25 mm presser foot values reflect the inclusion of the specificationspreviously enumerated in Section 5.1.5 of Test Method D 926. The 25 mm
31、 presser foot is deprecated in favor of the 16 mm presser foot. However, the 25mm presser foot may continue to be used for Test Method D 926, provided themass given in the table above is employed.D3767033dimension being measured.Repeat the procedure again with the test specimen removed,and the diffe
32、rence between readings is the dimension of the testspecimen.The pressure exerted by the presser foot shall be:22 6 5 kPa (3.2 6 0.7 psi) (refer to Table 1) for solid rubberhaving a hardness equal to or greater than 35 IRHD and10 6 2 kPa (1.5 6 0.3 psi) for solid rubber having a hardnessless than 35
33、IRHD (see Test Method D 1415 ). The presser footshall not extend over the edge of the area of the test specimen(see Note 1).9.1.3.2 When using an instrument equivalent to the oneshown in Fig. 2, the micrometer is adjusted so that the presserfoot is resting freely on the (polished granite) base.The m
34、icrometer is then reset to a “zero” reading. The presserfoot is then raised with the lifting lever mechanism.The test specimen is placed beneath the presser foot.The presser foot is lowered gently to the test specimen.Read and record the thickness from the micrometer to anaccuracy within 1 % of the
35、dimension being measured imme-diately after the presser foot contacts the test specimen.The reading displayed digitally is the dimension of the testspecimen to within the tolerance (resolution) of the instrument.The pressure exerted by the presser foot shall be 22 6 5 kPa(3.2 6 0.7 psi) (refer to Ta
36、ble 1) for solid rubber having ahardness equal to or greater than 35 IRHD, and 10 6 2 kPa (1.56 0.3 psi) for solid rubber having a hardness of less than 35IRHD.The presser foot shall not extend beyond the edge of the testspecimen (see Note 1).9.1.3.3 This practice allows for a range of masses to be
37、usedin concert with a foot of a given diameter (). This is toaccommodate the inherent frictional resistance of the gagemechanism, as well as the additional force introduced by themass of the gage assembly.9.1.3.4 In Table 1, the “Optimal Mass” may be consider thatwhich would cause the force (kPa / p
38、si) to be applied by a footof the stated diameter with no gage or mechanism involved, asif by gravity. The “maximum” and “minimum” values shownin Table 1 are those that are defined by the upper and lowerlimits, for example, 22 6 5 kPa / 3.2 6 0.7 psi and 10 6 2kPa / 1.5 6 0.3 psi.NOTE 1The operator
39、should take care to ensure that the micrometerand guide post assembly is perpendicular to the granite base or other testspecimen support surface to within a tolerance of 60.002 in. Theperpendicularity should be ascertained with the micrometer at the oper-ating height.9.2 Procedure A1:9.2.1 ScopeThis
40、 procedure is intended for use in deter-mining the thickness of test specimens with irregular, convex,or concave surfaces, using a micrometer with a spherical foot.It is particularly suitable for compression set test specimens.9.2.2 ApparatusThe apparatus shall consist of a microme-ter (such as dial
41、 or digital-electronic) of one of the followingconfigurations:9.2.2.1 Two contact members with domed surfaces ofspherical radius 12.5 6 0.1 mm or 0.5 6 0.005 in. formed onrods 9.5 to 10 mm (0.38 to 0.4 in.) in diameter. The contactmembers shall exert a force of 0.8 6 0.1 N (0.18 6 0.02 lbf)and shall
42、 have a scale capable of measuring dimensions to anaccuracy within 1 % of the dimension being measured. Thereading, if displayed digitally, is the dimension of the testspecimen to within the tolerance (resolution) of the instrument.9.2.2.2 Two contact members with domed surfaces ofspherical radius 1
43、2.5 6 0.1 mm or 0.5 6 0.005 in. in diameter,one as an anvil insert, the other connected to the micrometer.The contact members shall exert a force of 0.8 6 0.1 N (0.186 0.02 lbf) and shall have a scale capable of measuringdimensions to an accuracy within 1 % of the dimension beingmeasured. The readin
44、g displayed digitally is the dimension ofthe test specimen to within the tolerance (resolution) of theinstrument. The anvil is a solid insert with an integral orreplaceable contact foot placed in the Bradnick-Warner fixture(see Fig. 3). The contact foot with a domed surface of sphericalradius is pla
45、ced in the micrometer.NOTE 2The fixture depicted in Fig. 3 bears the names of its designersand is intended to be reproduced freely.9.2.2.3 A flat anvil 9.5 6 0.5 mm (0.38 6 0.02 in.) indiameter, and a spherical contact foot 6.0 6 1 mm (0.246 0.04in.) in diameter. The contact foot shall exert a force
46、 of 0.86 0.1N (0.18 6 0.02 lbf) and shall have a scale capable of measuringdimensions to an accuracy within 1 % of the dimension beingmeasured. The reading, if displayed digitally, is the dimensionof the test specimen to within the tolerance (resolution) of theinstrument.9.2.2.4 A spherical contact
47、foot 6.0 6 1.0 mm (0.24 6 0.04in.) in diameter (see Fig. 4). The contact foot shall exert a forceof 0.8 6 0.1 N (0.18 6 0.02 lbf) and shall have a scale capableof measuring dimensions to an accuracy within 1 % of thedimension being measured. The reading displayed digitally isthe dimension of the tes
48、t specimen to within the tolerance(resolution) of the instrument. A solid anvil insert 9.5 6 0.5mm (0.38 6 0.02 in.) in diameter extending at least 0.50 in.above the surface of the base plate of the Bradnick-Warnerfixture (see Fig. 3).9.2.3 Procedure A1:9.2.3.1 When using the instrument described in
49、 9.2.2.1,place the central portion of the test specimen between the twodomed surfaces and lower the presser foot gently until itcontacts the surface of the test specimen. Read and record thethickness from the micrometer to an accuracy within 1 % of thedimension being measured immediately after the presser footcontacts the test specimen (see Note 1).9.2.3.2 When using an instrument described in 9.2.2.2 (seeFig. 4), the micrometer is adjusted so that the presser foot isresting freely on the solid anvil with integral or replaceablespherical foot (see Fig. 3). Ca
