1、Designation: D378 10D378 10 (Reapproved 2016)Standard Test Methods forRubber (Elastomeric) Conveyor Belting, Flat Type1This standard is issued under the fixed designation D378; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar 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. Scope1.1 These test methods (and references) cover the procedures for evaluating the physical properties of flat conveyor
3、 belting.Performance criteria for belting will not be detailed here, but can be found through the RMA (Rubber Manufacturers Association)Conveyor and Elevator Belt Handbook, ANSI (American National Standards Institute), various governmental authorities, and theInternational Organization for Standardi
4、zation (ISO). Belting for conveying and elevating materials generally is designated anddefined as follows:1.1.1 Heavy Duty ConveyorA heavy duty belt is defined as belting designed for bulk haulage of materials, such as stone,crushed rock, sand, metals ores, coal, wood chips, etc., and has a carcass
5、strength (design) substantial enough to withstandconveyor system tensions of 160 PIW2 (pounds per inch of width) and above.1.1.2 Light Duty ConveyorA light duty belt is defined as belting designed for conveying a variety of lower weight (density)materials, packages, industrial and electronic goods,
6、and food products. These belts often are shorter in length and width, with lessoverall thickness than heavy duty belting, and are generally used in conveyor systems with tensions less than 160 PIW.1.1.3 General DescriptionBelting can have elastomeric coverings on one side, both sides, or neither sid
7、e depending upon thespecific application requirements. Belt coverings are comprised of various synthetic or natural rubber polymers, PVC, or otherelastomeric materials, dependent upon application or customer requirements. The strength (load bearing) member(s) of mostbelting generally is a woven or i
8、nterwoven carcass of synthetic or natural fibers, such as, but not limited to, polyester, nylon,polyaramide and cotton, as well as steel (cable/cord type or woven mesh).1.2 This standard does not purport to address all of the application specific testing available or safety concerns, if any,associat
9、ed with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices anddetermine the applicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D412 Test Methods for Vulcanized Rubber and Thermoplastic Elast
10、omersTensionD413 Test Methods for Rubber PropertyAdhesion to Flexible SubstrateD471 Test Method for Rubber PropertyEffect of LiquidsD573 Test Method for RubberDeterioration in an Air OvenD624 Test Method for Tear Strength of Conventional Vulcanized Rubber and Thermoplastic ElastomersD865 Test Method
11、 for RubberDeterioration by Heating in Air (Test Tube Enclosure)D1149 Test Methods for Rubber DeteriorationCracking in an Ozone Controlled EnvironmentD1415 Test Method for Rubber PropertyInternational HardnessD1894 Test Method for Static and Kinetic Coefficients of Friction of Plastic Film and Sheet
12、ingD2240 Test Method for Rubber PropertyDurometer HardnessD3183 Practice for RubberPreparation of Pieces for Test Purposes from ProductsD3767 Practice for RubberMeasurement of DimensionsD4483 Practice for Evaluating Precision for Test Method Standards in the Rubber and Carbon Black Manufacturing Ind
13、ustriesD5963 Test Method for Rubber PropertyAbrasion Resistance (Rotary Drum Abrader)1 These test methods are under the jurisdiction of ASTM Committee D11 on Rubber and Rubber-like Materials and are the direct responsibility of Subcommittee D11.31on Rubber Hose and Belting.Current edition approved O
14、ct. 1, 2010Nov. 1, 2016. Published November 2010December 2016. Originally approved in 1991. Last previous edition approved in 20082010as D378 00 (2008).D378 10. DOI: 10.1520/D0378-10.10.1520/D0378-10R16.2 PIW is not an SI unit.3 For referencedASTM standards, visit theASTM website, www.astm.org, or c
15、ontactASTM 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 indication of what changes have
16、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 considered the official docum
17、ent.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.2 ISO Standards:4ISO 282 Conveyor BeltsSamplingISO 283 Textile Conveyor BeltsFull Thickness Tensile Strength, Elongation at Break and Elongation at the ReferenceLoadTest MethodISO
18、284 Conveyor BeltsElectrical ConductivitySpecification and Test MethodISO 340 Conveyor BeltsLaboratory Scale Flammability CharacteristicsRequirements and Test MethodISO 505 Conveyor BeltsMethod for the Determination of the Tear Propagation Resistance of Textile Conveyor BeltsISO 4649 RubberDetermina
19、tion of Abrasion Resistance Using a Rotating Cylindrical Drum DeviceISO 7590 Steel Cord Conveyor BeltsMethods for the Determination of Total Thickness and Cover ThicknessISO 76221 Steel Cord Conveyor BeltsLongitudinal Traction TestPart 1: Measurement of ElongationISO 76222 Steel Cord Conveyor BeltsL
20、ongitudinal Traction TestPart 2: Measurement of Tensile StrengthISO 7623 Steel Cord Conveyor BeltsCord-to-Coating Bond TestInitial Test and After Thermal TreatmentISO 8094 Steel Cord Conveyor BeltsAdhesion Strength Test of the Cover to the Core LayerISO 9856 Conveyor BeltsDetermination of Elastic an
21、d Permanent Elongation and Calculation of Elastic Modulus2.3 RMA Technical Bulletins and Test Methods:5RMA IP-1 Conveyor and Elevator Belt Handbook2.4 U.S. Mine Safety and Health Administration (MSHA):630 CFR 14 Requirements for the Approval of Flame-Resistant Conveyor Belts30 CFR 18.65 Flame Test o
22、f Hose3. Summary of Test Methods3.1 ASTM test methods are specified to the extent that they can be applied to testing of flat belts.3.2 Some of the test methods specified for flat belts are specific to flat belts only and do not appear in any otherASTM standard;however, some of these may involve use
23、 of ASTM test methods.3.3 The test methods include the following:Test Methods SectionMeasurement of Dimensions 8Physical Properties of Elastomeric Covers 9Immersion Tests 10Adhesion Tests 11Breaking Strength and Modulus Testing 12Flame Test for Belting 13Carcass Tear Test 14Troughability Test 15Brea
24、king Strength of Mechanical Fastenings (Static Test Method) 16Elevator Belt Bolt Holding Strength Test 17Steel Cord/Cable Belt Testing 184. Significance and Use4.1 Flat conveyor belts are used in many industrial applications in which they are subjected to a great variety of stresses andconditions. S
25、ervice conditions can be calculated or measured. Design levels and test requirements are established bymanufacturers, or end-users, or both. The tests (test methods) are used to measure the characteristics of conveyor belting as theyrelate to service conditions.4.2 The tests outlined by these test m
26、ethods are commonly applied by belt manufacturers to control the quality of their products.4.3 Research and product development activities in flat belting involve extensive testing as outlined by these test methods.4.4 In case of conflict between the provisions of these test methods and those of det
27、ailed specifications or test methods for aparticular belt, the latter shall take precedence.4.5 In case of conflict between the provisions of these test methods and those of detailed specifications or test methods for aparticular belt, the latter shall take precedence.5. Sampling5.1 Test samples sha
28、ll be the full width and thickness of the belt and shall be of sufficient length and width to perform the desiredtests.4 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.5 Available from the Rubber Manufacturers Associatio
29、n, 1400 K St. N.W., Suite 900, Washington D.C. 20005, www.rma.org.6 Available from Mine Safety then, strip the elastomeric cover from one surface and measure the thickness of the carcass,including the remaining cover. The difference between the first and second measurements will represent the thickn
30、ess of the coverremoved. Follow the same procedure on the test specimen from which the first cover has been removed when the thickness of theother cover is required. The test specimen may consist of a small section cut from the belt. In many cases, especially with PVCor TPE (thermoplastic elastomer)
31、 belting of interwoven (solid woven) carcass construction, the covers cannot be removed withoutdistorting the sample. Buffing, to remove thermoplastic cover(s) from the specimen, may be necessary. In other cases, a hand-heldmicrometer or optical micrometer is used to measure the thickness of the com
32、ponents.8.5 Thickness of Cover When a Breaker Is UsedThe thickness of the cover shall include the breaker, unless otherwisespecified.9. Physical Properties Of Elastomeric Covers Or Belt Surfaces (Or Both)ScopeA number of specific test procedures for determining a variety of physical properties of co
33、nveyor belt cover materialare detailed in this section. These tests are extensive and are referenced to established test procedures; primarily existing ASTMand ISO standards. It is beyond the scope and necessity of this section to detail every procedure in its entirety. This section isintended to se
34、rve as a guide for the testing of these materials. The routine tests (and references) for tensile, elongation, hardness,tear resistance, and accelerated aging are covered through Section 9.6. More specific tests (references) for other properties, suchas coefficient of friction, abrasion resistance,
35、ozone deterioration, and static conductivity are covered through Sections 9.7 9.10,respectively.9.1 ApparatusThe dies, bench marker, stamp, pad, micrometer, testing machine, testing machine grips, and calibration of thetesting machine shall conform to Test Methods D412.9.2 Test Specimens:9.2.1 Prepa
36、ration of Cover PiecesSeparate the covers from the carcass according to Practice D3183. Buff the covers ifnecessary to obtain smooth parallel surfaces. If possible, cover pieces should be about 150 mm (6 in.) long, at least 25 mm (1 in.)wide, and 2.0 60.2 mm (0.08 60.008 in.) thick. In no case shall
37、 the thickness exceed 3 mm (0.12 in.) or be less than 1 mm (0.04in.).Ameat slicer or commercial skiving tool can be used to remove adequate sample specimens from the belt cover. If cover piecesD378 10 (2016)3cannot be obtained from the belt, molded sheets prepared from the same unvulcanized rubber c
38、ompound with an equivalent stateof vulcanization may be requested from the belt manufacturer.9.2.2 Preparation of Test SpecimenThe test specimen shall be stamped out from the separated cover with a steel dieconforming to A, B, or C of Fig. 1 of Test Methods D412. Die B shall be used when the size of
39、 the sample and the tension andstretch limits of the testing machine permit, with exceptions as explained below. If the tension limit is too low for the machine,Die A shall be used. If the stretch limit is too high for the machine, Die C shall be used. Die C shall be used for samples that aretoo sma
40、ll for Die A or B.9.2.3 MarkingDumbbell specimens shall be marked with the prescribed stamp pad and either of the prescribed bench markersdescribed in Test Methods D412. Aged or immersed dumbbell specimens shall be marked after oven aging or immersion testing.9.3 ProcedureUse the procedure for tensi
41、le testing, measuring and recording in accordance with Test Methods D412. Measureand record the elongation to the nearest 10 % of the original distance between bench (reference) marks.9.3.1 Calculations:9.3.2 Tensile StrengthThe tensile strength (stress) is the applied force relative to the original
42、 cross-sectional area. It iscalculated by dividing the force in N (lbf) by the cross-sectional area of the unstressed specimen in square meters (in.2) and isexpressed in MPa or psi.9.3.3 ElongationThe elongation (strain) is the extension between bench (reference) marks, produced by a tensile force a
43、ppliedto a specimen, relative to the original distance between the marks. It is calculated by dividing the distance extended beyond theoriginal distance by the original distance and is multiplied by 100 to get percent.9.4 Cover HardnessRefer to either Test Method D1415 or D2240 for procedures and ca
44、lculation. The values should beexpressed in International Hardness or Durometer Hardness units.9.5 Cover Tear TestTesting is conducted per Test Method D624. Results are expressed in units of pounds per inch (thickness),ppi, or kilo Newtons per meter, kN/m. The type die, B, C, or trouser test method
45、shall be included in the test report. Preparationof the samples is accomplished as described in 9.2.1.9.6 Procedure For Physical Properties Of Elastomeric Covers After Heat AgingProceed in accordance with either TestMethod D573 or D865.9.7 Coeffcients Of Friction, Static And KineticTest Method D1894
46、 is used to determine relative values for these surfaceproperties.9.8 Abrasion ResistanceTest methods used and referred to most frequently in the conveyor belt industry are Test MethodD5963 and ISO 4649.9.9 Ozone ResistanceThe effect of exposure to ozone is determined by Test Methods D1149 with resu
47、lts reported as pass/fail(cracking) for exposures to specified ozone concentrations in parts per hundred million (pphm), at specific temperatures and timeduration(s).9.10 Electrical Surface ResistanceThe electrical surface characteristics of conveyor belting are tested based on the originalRMA proce
48、dure (RMA 808) since adopted as ISO 284. An abbreviated procedure for this testing is detailed.9.10.1 PrincipleAn electrical current of specified voltage is passed through electrodes of a suitably prepared test piece takenfrom the belt.9.10.2 Apparatus (see Fig. 1):9.10.2.1 A sheet of insulating mat
49、erial slightly larger than the test specimen.9.10.2.2 Two cylindrical and coaxial brass electrodes, the base of one being circular and the other annular.The circular electrodewill have an OD of 150 mm (6 in.) and an ID of 125 mm (5 in.) and a height of 22 mm (0.9 in.), with a mass of 900 g (31.8 oz).FIG. 1 Apparatus for Testing of Electrical Surface ResistanceD378 10 (2016)4The annular electrode has a diameter of 25 mm (1 in.) and a height of 32 mm (1.25 in.), with a mass of 115 g (4.06 oz). The basesof these electrodes wi
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