1、Designation: D3786/D3786M 12 D3786/D3786M 13Standard Test Method forBursting Strength of Textile FabricsDiaphragm BurstingStrength Tester Method1This standard is issued under the fixed designation D3786/D3786M; the number immediately following the designation indicates theyear of original adoption o
2、r, in the case of revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () 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
3、.1 This test method describes the measurement of the resistance of textile fabrics to bursting using a hydraulic or pneumaticdiaphragm bursting tester. This test method is generally applicable to a wide variety of textile products.1.2 This test method may also be applicable for stretch woven and wov
4、en industrial fabrics such as inflatable restraints.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values
5、from thetwo systems may result in non-conformance with the standard.NOTE 1For the measurement of the bursting strength by means of a ball burst mechanism, refer to Test Method D3787.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the r
6、esponsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD37
7、87 Test Method for Bursting Strength of TextilesConstant-Rate-of-Traverse (CRT) Ball Burst TestD4850 Terminology Relating to Fabrics and Fabric Test Methods2.2 Other Standard:TAPPI Method T 403 , Bursting Strength of Paper33. Terminology3.1 For all terminology related to D13.59, Fabric Test Methods,
8、 see Terminology D4850.3.1.1 The following terms are relevant to this standard: bursting strength, knitted fabric, nonwoven fabric, stretch woven fabric,woven fabric.3.2 For all other terminology related to textiles, see Terminology D123.4. Summary of Test Method4.1 A specimen is clamped over an exp
9、andable diaphragm. The diaphragm is expanded by fluid pressure to the point ofspecimen rupture. The difference between the total pressure required to rupture the specimen and the pressure required to inflatethe diaphragm is reported as the bursting strength.1 This test method is under the jurisdicti
10、on of ASTM Committee D13 on Textiles and is the direct responsibility of Subcommittee D13.59 on Fabric Test Methods, General.Current edition approved Dec. 15, 2012Jan. 1, 2013. Published January 2013. Originally approved in 1979. Last previous edition approved in 20092012 as D378609.12.DOI: 10.1520/
11、D3786_D3786M-12.10.1520/D3786_D3786M-13.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM 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 T
12、echnical Association of the Pulp and Paper Industry (TAPPI), 15 Technology Parkway South, Norcross, GA 30092, http:/www.tappi.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. B
13、ecauseit 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 document.Copyright ASTM International, 10
14、0 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Significance and Use5.1 This method for the determination of diaphragm bursting strength of knitted, nonwoven and woven fabrics is being usedby the textile industry for the evaluation of a wide variety of end uses.5
15、.2 In cases where test results obtained using the procedures in Test Method D3786 have not been correlated with actualperformance, Test Method D3786 is considered satisfactory for acceptance testing of commercial shipments of textile fabrics forbursting strength since the method has been used extens
16、ively in the trade for acceptance testing. In cases where disagreementarising from differences in values reported by the purchaser and the supplier when using Test Method D3786 for acceptance testing,the statistical bias, if any, between the laboratory of the purchaser and the laboratory of the supp
17、lier should be determined withcomparison based on testing specimens randomly drawn from one sample of material of the type being evaluated.NOTE 2The kind of load transfer and stretch that occur when knitted goods and nonwoven fabrics are worn are prevented by clamping them asdescribed in this method
18、.6. Apparatus and Materials6.1 Inflated Diaphragm Bursting Tester 4 A testing machine that meets the requirements of 6.1.1-6.1.4. Mounted so as to befree of externally induced vibrations.6.1.1 Clamps, for firmly and uniformly securing the test specimen between two annular, parallel, and durable surf
19、aces, withoutslippage during the test. Use sufficient pressure to effect the practicable minimization of slippage. The upper and lower clampingsurfaces shall have a circular coaxial aperture of 31 6 0.75 mm (1.22 6 0.03 in.) in diameter: The surfaces of the clamps shallbe durable and any edge which
20、might cause a cutting action shall be rounded to a radius of not more than 0.4 mm. The lower clampshall be integral with the chamber in which a pressure medium inflates the rubber diaphragm.NOTE 3Since the clamping mechanism and clamping surfaces are subject to considerable wear and distortion, they
21、 should be examined periodicallyand repaired or replaced when necessary. The effectiveness of grooving the clamping surfaces in the manner specified has not been determined.6.1.2 DiaphragmA diaphragm of molded synthetic or natural rubber, clamped between the lower clamping plate and the restof the a
22、pparatus so that before the diaphragm is stretched by pressure underneath it the center of its upper surface is nominallylevel with the plane of the clamping surface. The diaphragm should be inspected frequently for permanent distortion and renewedas necessary.6.1.3 Pressure GageThe instrument must
23、be fitted with a pressure measuring system, accurate throughout the entire range ofits scale to within a value of 1 % of its maximum capacity. For those instruments with a Bourdon type gage the capacity of thegage shall be such that the individual readings will be not less than 25 % nor more than 75
24、 % of the total capacity of the gage.6.1.4 Pressure SystemA means of applying controlled increasing pressure to the underside of the diaphragm until thespecimen bursts. This can be achieved by two methods; hydraulic or pneumatic.6.1.4.1 Hydraulic pressure is produced by a fluid displaced at the rate
25、 of 95 6 5 mL/min. The fluid is displaced by a piston inthe pressure chamber of the apparatus. The recommended chamber fluid is USP chemically pure 96 % glycerin.NOTE 4Ethylene glycol may be substituted for the glycerine if desired.6.1.4.2 Pneumatic pressure is produced by controlling the flow of cl
26、ean dry air through a valve. The valve is configured as per11.4.16.1.5 Aluminum Sheet For Checking Performance of Tester5Pieces of pretested aluminum sheet having a known burstingstrength in the range of 70 to 790 kPa (10 to 115 psi) may be used for checking the overall performance of the tester.NOT
27、E 5Use of an aluminum sheet from one tester manufacturer may not be suitable for burst testing machines from other tester manufacturers.Manufacturers instructions for checking should be followed.6.1.6 Pressure Recording.6.1.6.1 Hydraulic InstrumentsMeans shall be provided at the instant of rupture o
28、f the specimen for stopping any furtherapplication of the loading pressure and for holding unchanged the contents of the pressure chamber until the total bursting pressureand the pressure required to inflate the diaphragm indicated on the gage have been recorded.6.1.6.2 Pneumatic InstrumentsMeans sh
29、all be provided for recording the loading pressure at the point of rupture. Diaphragmcorrection (tare pressure) is achieved by inflating the diaphragm to the same distension recorded at bursting and recording theamount of pressure to achieve this.7. Sampling7.1 Lot SampleAs a lot sample for acceptan
30、ce testing, take at random the number of rolls of fabric directed in an applicablematerial specification or other agreement between the purchaser and the supplier. Consider rolls of fabric to be the primarysampling units.4 Hydraulic and pneumatic bursting strength testers and accessories are commerc
31、ially available.5 Standardized aluminum sheets are commercially available.D3786/D3786M 132NOTE 6An adequate specification or other agreement between the purchaser and the supplier requires taking into account the variability between rollsof fabric and between specimens from a swatch from a roll of f
32、abric to provide a sampling plan with a meaningful producers risk, consumers risk,acceptable quality level, and limiting quality level.7.2 Laboratory SampleAs a laboratory sample for acceptance testing, take a full width swatch 1 m (1 yd) long from the endof each roll of fabric in the lot sample, af
33、ter first discarding a minimum of 1 m (1 yd) of fabric from the very outside of the roll.From each roll or piece of circular knit fabric selected from the lot sample, cut a band at least 305 mm (1 ft) wide.7.3 Test SpecimensCut ten test specimens from each swatch in the laboratory sample with each s
34、pecimen being 125 mm (5in.) square.8. Calibration8.1 Routine Verification of Testing MachineThe operation of the testing machine may be checked periodically (such as onceeach month) by bursting five specimens of standard aluminum sheet. The average of the indicated bursting resistance for the fivesp
35、ecimens of aluminum sheet should be between 65 % of that marked on the package of the pretested aluminum sheet standard.Use of the aluminum sheet may not be suitable for all burst testing machines. See the manufacturers instructions for routineverification procedures applicable to individual testing
36、 machines.8.2 Calibration of Pressure Measuring SystemCalibrate the pressure measuring system, while inclined at the same angle atwhich it is used, by means of a dead-weight tester of the piston type. Alternatively, a traceable electronic pressure gage may beused or other calibration instrumentation
37、 recommended by the equipment manufacturer. Such calibration is preferably carried outwith the gage in its normal position in the tester.8.3 Where agreement is not attained, check the tester according to the instructions given in TAPPI Method T 403.NOTE 7Possible causes of low readings are gage erro
38、r (bias or nonlinearity), gage expansivity too high, excessive gage pointer friction, air inhydraulic system or gage, diaphragm collapsed too far at zero, and low pumping rate (hand-driven tester). Possible causes of high readings are: gage error(bias nonlinearity), loose gage pointer (overshoot), g
39、age pointer bent by stop-pin, insufficient clamping force (slipping), nonuni-form clamping (partialslipping), stiff or inelastic diaphragm, diaphragm above clamping plate at zero, multiple sheet testing, high pumping rate (hand-driven tester), and doublebursts. If a gage is accidentally used beyond
40、its capacity, it must be recalibrated before it is used again.9. Conditioning9.1 Bring the specimens (or laboratory samples) from the prevailing atmosphere to moisture equilibrium for testing in thestandard atmosphere for textile testing as directed in Practice D1776.10. Selection and Number of Spec
41、imens10.1 Unless otherwise agreed upon, as when specified in an applicable material specification, take ten specimens of thelaboratory sample(s) of fabric. Each specimen shall be at least 125 mm (5 in.) square, or a circle 125 mm (5 in.) in diameter.Specimens need not be cut for testing. No two spec
42、imens from knitted fabric should contain the same wale or course yarns. Takeno specimens nearer the selvage than one tenth the fabric width. This restriction does not apply to tubular knitted fabric.11. Procedure11.1 Make all tests on specimens conditioned in the standard atmosphere for testing text
43、iles as directed in 9.1.11.2 Hand Driven Hydraulic Tester:11.2.1 Insert the conditioned specimen under the tripod, drawing the specimen taut across the plate, and clamp specimen inplace by bringing the clamping lever as far to the right as possible.NOTE 8For specimens with considerable stretch, it m
44、ay be necessary to extend the fabric uniformly over the plate to remove some of the stretchbefore clamping.11.2.2 Rotate the hand wheel, clockwise at a uniform speed of 120 rpm until the specimen bursts.11.2.3 Stop turning the hand wheel at the instant of rupture of the specimen (see Note 9).11.2.4
45、Immediately after rupture and in rapid succession, release the clamping lever over the specimen. Immediately release thestrain on the diaphragm by turning the wheel counterclockwise to its starting position and record the pressure required to inflatethe diaphragm (tare pressure). Record the total pr
46、essure required to rupture the specimen.NOTE 9If the pressure stops increasing, as indicated by the dial, and the specimen has not broken, push the operating lever to remove the pressure.Record that the stretch of the fabric exceeds the dimensional limitations of the tester. If slippage of the speci
47、men is noted, discard the result and use anew specimen.11.3 Motor-Driven Hydraulic Tester:11.3.1 Insert the specimen between the top and bottom clamp ensuring that the specimen is free from creases and folds. Securelyclamp the specimen in place by following the manufacturers instructions appropriate
48、 to the machine. Apply pressure to thespecimen until it bursts.11.3.2 Diaphragm Correction (Tare Pressure)Using the same settings as employed to burst the specimen, record the pressurerequired to distend only the diaphragm to the same height as used to burst the specimen.D3786/D3786M 13311.4 Pneumat
49、ic Tester:11.4.1 Adjust the control valve of the bursting tester so that the mean time to distend a specimen to burst falls within (20+/-5)s. Preliminary trials may be needed to fix the correct setting of the control valve. Time to burst is to be recorded between thebeginning of vaulting and the bursting of the test specimen.11.4.2 Clamp the specimen securely. Ensuring that the specimen does not slip. Place the distension recording device into themeasuring position and adjust it to the zero position. Fasten the safety cover in position according to m
