1、Designation: D7255 061D7255 14Standard Test Method forAbrasion Resistance of Leather (Rotary Platform, Double-HeadAbraser Method)1This standard is issued under the fixed designation D7255; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revi
2、sion, the 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.1 NOTEIn Note 2, the reference to H-19 was editorially corrected to H-18 in September 2006.1. Scope1.1 This test
3、 method covers the determination of the abrasion resistance of leather using the rotary platform, double-head tester(RPDH).platform abraser.NOTE 1This test method is similar but not equivalent to ISO 17076-1, and results should not be directly compared between the two methods.1.2 The values stated i
4、n SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 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 h
5、ealth practices and to determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1517 Terminology Relating to LeatherD1610 Practice for Conditioning Leather and Leather Products for TestingD2240 Test Method for Rubber PropertyDurometer HardnessD281
6、3 Practice for Sampling Leather for Physical and Chemical TestsG195 Guide for Conducting Wear Tests Using a Rotary Platform Abraser2.2 Other Standards:3ISO 17076-1 Leather-Determination of abrasion resistance Part 1-Taber method3. Terminology3.1 Definitions:3.1.1 abrasera wear testing instrument, al
7、so referred to as a rotary platform, double head (RPDH) platform tester or abrader.3.1.2 abrasionthe wearing away of any part of a material by rubbing against another surface.3.1.3 abrasion cyclein abrasion testing, one or more movements of the abradant across a material surface, or the materialsurf
8、ace across the abradant, that permits a return to its starting position. In the case of the rotary platform test method, it consistsof one complete rotation of the specimen.3.1.4 durabilitythe ability to withstand deterioration or wear out in use, including the effects of abrasion.3.1.5 resurfacethe
9、 preparation of an abrasive wheel on a resurfacing disk or diamond tool wheel refacer, prior to use in testing.3.2 For definitions of other leather terms used in this test method, refer to Terminology D1517.4. Summary of Test Method4.1 A specimen is abraded using rotary rubbing action under controll
10、ed conditions of pressure and abrasive action. The testspecimen, mounted on a turntable platform, turns on a vertical axis, against the sliding rotation of two abrading wheels. One1 This test method is under the jurisdiction of ASTM Committee D31 on Leather and is the direct responsibility of Subcom
11、mittee D31.05D31.07 on UpholsteryPhysicalProperties.Current edition approved April 1, 2006April 1, 2014. Published April 2006May 2014. Originally approved in 2006. Last previous edition approved in 2006 as D7255-061.DOI: 10.1520/D7255-06E01.10.1520/D7255-14.2 For referencedASTM standards, visit theA
12、STM website, 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.3 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY
13、10036, http:/www.ansi.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends th
14、at users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1abrading wheel rubs th
15、e specimen outward toward the periphery and the other, inward toward the center. The resulting abrasionmarks form a pattern of crossed arcs over an area of approximately 30 cm2. Resistance to abrasion is evaluated by visual inspectionof damage to the specimen or change in weight, as described in Sec
16、tion 14.5. Significance and Use5.1 The resistance of leather to abrasion, as measured on a testing machine in the laboratory, is generally only one of severalfactors contributing to wear performance or durability as experienced in the actual use of the material. While “abrasion resistance”(often sta
17、ted in terms of the number of abrasion cycles) and “durability” (defined as the ability to withstand deterioration or wearout in use, including the effects of abrasion) are frequently related, the relationship varies with different end uses and differentfactors may be necessary in any calculation of
18、 predicted durability from specific abrasion data. This test method provides acomparative ranking of material performance, which can be used as an indication of relative end-use performance.5.2 The resistance of leather to abrasion may be affected by factors including test conditions, type of abrada
19、nt, pressure betweenthe specimen and abradant, mounting or tension of the specimen, and type, kind, or amount of finishing materials.5.3 Abrasion tests utilizing the rotary platform, double-head tester platform abraser may be subject to variation due to changesin the abradant during specific tests.
20、Depending on abradant type and test specimen, the wheel surface may change (that is, becomeclogged) due to the pick up of finishing or other materials from test specimens and must be cleanedresurfaced at regularly definedintervals.5.4 The measurement of the relative amount of abrasion may also be af
21、fected by the method of evaluation and may be influencedby the judgment of the operator.6. Apparatus6.1 Rotary Platform, Double-Head (RPDH) Tester, Platform Abraser, 4 as described in Guide G195 and consisting of theelements described in 6.1.1 6.1.5 (see Fig. 1).6.1.1 A turntable platform, which is
22、removable, parts provided with the turntable include the S19 that includes a rubber pad,clamp plate and nut, and centrally located threaded post and nut. When testing flexible specimens, the platform will also includea clamping ring to secure the specimen to the turntable. The turntable is motor dri
23、ven and mounted so as to produce a circularsurface travel of an essentially flat specimen in the plane of its surface,6.1.2 A motor capable of rotating the turntable platform at a speed of either 72 6 2 r/min for 110 V/60 Hz or 60 6 2 r/minfor 230 V/50 Hz,6.1.3 A pair of pivoted arms to which the ab
24、rasive wheels and accessory weights or counterweights are attached,NOTE 2Without auxiliary weights or counter weights applied, each arm will apply a load against the specimen of 250 6 1 g (exclusive of the massof the wheel itself).4 Available from Taber Industries, 455 Bryant Street, North Tonawanda
25、, NY 14120.FIG. 1 Rotary Platform, Double-Head TesterAbraserD7255 1426.1.4 A vacuum suction system and vacuum pickup nozzle to remove debris and abrasive particles from the specimen surfaceduring testing. The height of the vacuum pickup nozzle shall be adjustable, and will have two openings with one
26、 openingpositioned between the two wheels and over the wear path and the other placed diametrically opposite. The distance between theaxes of the two openings shall be 76.0 6 1.0 mm, and6.1.5 A counter to record the number of cycles (revolutions) made by the turntable platform.6.2 Abrasive Wheels, 5
27、 which are attached to the free end of the pivoted arms, and are able to rotate freely about horizontalspindles. The abrasive wheels are either resilient or vitrified based, with both types of wheels consisting of hard particles embeddedin a binder material and manufactured in different grades of ab
28、rasive quality.6.2.1 Their internal faces shall be 52.4 6 1.0 mm apart and the hypothetical line through the two spindles shall be 19.05 6 0.3mm away from the central axis of the turntable (see Fig. 2). When resting on the specimen, the wheels will have a peripheralengagement with the surface of the
29、 specimen, the direction of travel of the periphery of the wheels and of the specimen at thecontacting portions being at acute angles, and the angles of travel of one wheel periphery being opposite to that of the other. Motionof the abrasive wheels, in opposite directions, is provided by rotation of
30、 the specimen and the associated friction there from.5 The sole source of supply of the apparatus known to the committee at this time is Taber Industries, 455 Bryant Street, North Tonawanda, NY 14120. If you are awareof alternative suppliers, please provide this information toASTM International Head
31、quarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1 which you may attend.FIG. 2 Diagrammatic Arrangement of ApparatusD7255 1436.2.2 The wheels shall be 12.7 6 0.3 mm thick and have an external diameter of 51.9 6 0.5 mm when new, and in no ca
32、se lessthan 44.4 mm. The abrasive wheels are either resilient or vitrified based, with both types of wheels consisting of hard particlesembedded in a binder material and manufactured in different grades of abrasive quality.NOTE 3The H-18 wheels typically produce a harsher abrasion than the CS-17 whe
33、els, which produce a harsher abrasion than the CS-10 wheels.NOTE 4The S-35Tungsten Carbide wheels include 1 mm pitch 45 spiral pitch angle, helical teeth cut into its periphery.This wheel does not includehard particles embedded in a binder material, and typically produces severe cutting and abrasion
34、.6.2.3 Prior to testing, ensure the expiration date has not passed for resilient wheels. Follow the manufacturers recommendedpractice for breaking in new or resurfacing previously used wheel sets (see Section 10).NOTE 3The hardness of the resilient wheels can be checked with Test Method D2240. An ac
35、ceptable hardness for CS-10 and CS-17 wheels is 816 5 units on Shore Durometer A-2 Scale.6.3 Accessory Loads,Weights, which can be attached to the pivoted abrader arms to increase the load against the specimen to500 or 1000 g per wheel (exclusive of the mass of the wheel itself). itself), see 11.1.6
36、. Counterweight attachments of 125 or 175g are available to reduce the load against the specimen, and can be used with or without the accessory load.weights.6.4 Auxiliary Apparatus:6.4.1 Resurfacing disc4 (S-11), is used for resurfacing of resilient wheels.6.4.2 A soft bristle brush, to remove loose
37、 particles from the surface of the specimen after testing.6.4.3 Wheel refacer,4 for resurfacing vitrified wheels or correcting out of round wheels.6.4.4 Specimen mounting cards (for example, Part S-36-1),(S-36-1) or equivalent,4 a 108 mm round mounting card with a 6.35mm center hole and one side coa
38、ted with pressure-sensitive adhesive used for mounting specimens. Use of the mounting card isnot required when using a clamping ring. If using a weight loss method of evaluation and a mounting card, the mounting cardsshould be conditioned in the standard testing environment before use (see Section 1
39、2).7. Sampling7.1 Take a lot sample as described in Practice D2813, or as agreed upon by the interested parties. Because leather is a naturalproduct, the physical properties may vary depending on location on the hide, side or skin from which the test sample is taken.Random sampling of specimens from
40、 a predefined location and orientation minimizes test bias and variability.8. Number and Preparation of Test Specimens8.1 If the number of specimens to be tested is not specified by agreement between the interested parties, test three specimens.8.2 Cut a circular specimen approximately 100 to 110 mm
41、 in diameter, with a 6.35 mm diameter hole in the center of thespecimen. A sample cutter or die may be used for this purpose.8.2 Clean the back of the specimen with a soft bristle brush to remove any loose debris. Mount specimen to a roundspecimen-mounting card (such as S-36-1), ensuring that the sp
42、ecimen is free of folds, creases, or wrinkles.Avoid getting oil, water,grease, and so forth, on the specimen when handling.Using shears or an appropriate sample cutter, cut the specimen to size. Punchor cut a 6.5 mm diameter hole in the center of the specimen.8.2.1 When using a specimen mounting car
43、d, cut a circular specimen approximately 100 to 110 mm in diameter. Clean the backof the specimen with a soft bristle brush to remove any loose debris. Mount specimen to a round specimen-mounting card (suchas S-36-1), ensuring that the specimen is free of folds, creases, or wrinkles.8.2.2 Alternativ
44、ely, a sample of 130 6 5 mm diameter may be used, with or without a mounting card, and secured to theturntable with a clampclamping ring.8.3 If the leather has a pattern such as embossment, ensure that the specimen is a representative sampling of the pattern.8.4 Avoid getting oil, water, grease, and
45、 so forth, on the specimen when handling.9. Preparation of Apparatus9.1 LoadA load of 1000 g per wheel should be used, unless otherwise agreed upon by the interested parties.9.2 Vacuum Pickup NozzleThe height of the vacuum pickup nozzle should be set 7 6 1 mm above the specimen surface,unless otherw
46、ise agreed upon by the interested parties.9.3 Vacuum SuctionThe vacuum suction force should be adjusted to lift the abraded particles, but not lift the specimen. Whenthe suction nozzles are in position, the air pressure in the suction device shall be within the range stated in 11.1.5. A setting of 7
47、5- 100 has been found to be sufficient and should be used, unless otherwise agreed upon by the interested parties.NOTE 5Vacuum suction force may be influenced by the condition of the collection bag, which must be emptied or replaced on a regular basis. Anyconnection or seal leaks will also influence
48、 suction force.9.4 Selection of Wheel TypeThe CS-105 wheel should be used, unless otherwise agreed upon by the interested parties.D7255 14410. Standardization of Abrading Wheels10.1 Preparation of resilient abrading wheelsTo ensure that the abrading function of the wheels is maintained at a constant
49、level, prepare the resilient wheels following 10.1.1 10.1.4.10.1.1 Mount the selected resilient wheels on their respective flange holders, taking care not to handle them by their abrasivesurfaces. Adjust the load on each wheel to 1000 g or the load agreed upon between the interested parties.10.1.2 Mount the resurfacing disc (S-11) on the turntable and affix using the clamp plate and nut, and clampclamping ring.Lower the abrading headspivoted arms carefully until the wheels rest on the resurfacing disc. Place the vacuum pick-up nozzle inposition a
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