ASTM D5807-2018 6875 Standard Practice for Evaluating the Overpressurization Characteristics of Inflatable Restraint Cushions.pdf

1、Designation: D5807 18Standard Practice forEvaluating the Overpressurization Characteristics ofInflatable Restraint Cushions1This standard is issued under the fixed designation D5807; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,

2、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. Scope1.1 This practice covers the procedures and conditions usedto evaluate the physical performance of inflatable

3、restraintcushions during and after overpressurization testing at elevatedpressures capable of causing cushion bursting using air pres-surization equipment.1.2 The physical performance characteristics that may beobtained in conjunction with this practice are internal cushionpressures determined by in

4、strumentation and material integrity,determined by visual inspection.1.3 This practice is applicable to all inflatable restraintcushions.1.4 Procedures and apparatus other than those stated in thispractice may be used by agreement between purchaser andsupplier with the specific deviations from this

5、practice ac-knowledged in the report.1.5 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system are not exact equivalents; therefore, each systemmust be used independently of the other.1.6 This standard does not purport to a

6、ddress all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.7 This international standard was de

7、veloped in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced D

8、ocuments2.1 ASTM Standards:2D123 Terminology Relating to TextilesD6799 Terminology Relating to Inflatable Restraints3. Terminology3.1 Definitions:3.2 For all terminology relating to D13.20, InflatableRestraints, refer to Terminology D6799.3.2.1 The following terms are relevant to this standard:cushi

9、on, cushion overpressurization, deployment, inflatablerestraint, module, standard atmosphere for testing textiles.3.3 For all other terms related to textiles, see TerminologyD123.4. Summary of Practice4.1 Inflatable restraint cushions are tested under laboratoryconditions to evaluate cushion integri

10、ty when exposed tointernal cushion pressures greater than deployment pressures.If cushion rupture occurs, the rupture pressure, time to rupture,and mode of rupture are recorded.4.2 Inflatable restraint cushions are mounted into a teststand that allows for inflations under conditions that exceeddeplo

11、yment pressures. Instrumentation within the test standcharts inflation pressures versus time and may allow forphotographic review of the overpressurization sequence.4.3 Cushion overpressurization results are reviewed forpressure and time relationships, and post-inflation materialanalysis.5. Signific

12、ance and Use5.1 This practice is intended to be a general guideline forrepetitive testing, safe conduct of tests, and accurate data1This practice is under the jurisdiction ofASTM Committee D13 on Textiles andis the direct responsibility of Subcommittee D13.20 on Inflatable Restraints.Current edition

13、 approved July 1, 2018. Published July 2018. Originally approvedin 1995. Last previous edition approved in 2013 as D5807 08(2013). DOI:10.1520/D5807-18.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMSta

14、ndards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principl

15、es on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1collection for inflatable restraints. Cushion overpressurizationtesting may be

16、 used for design and production validation, formanufacturing process control, for lot acceptance, or for acombination thereof.5.2 This practice constitutes the conditions, apparatus, andprocedures by which inflatable restraints are commonly testedfor cushion overpressurization. It is intended to be

17、used as aguideline in establishing a cushion specification or equivalentdocument. The practices in the specification may deviate fromthe practices described herein when (based on experience)considerations of equipment, cushion design, or other factorsdictate otherwise.5.3 There exists a large variet

18、y in cushion configurationsand equipment designs, obviating a standard test method forcushion overpressurization. Therefore, a cushion specificationshould incorporate the practices stated herein when describinga test method for testing a specific cushion geometry andapparatus design. To ensure accur

19、acy and repeatability, thespecification should also address precision and bias in amanner consistent with ASTM prescribed procedures andconsistent with the particular cushion geometry, equipment inuse, and test procedures.5.3.1 Sources of variation in cushion overpressurizationtesting procedures inc

20、lude orifice size, attachment fixture,sensor location, method of attachment, presence or absence ofinternal bladder, accumulator size and pressure, transducertype and location, the presence or absence of tethers, presenceor absence of vent plugs, and the accuracy of timing devicesand pressure sensor

21、s. All sources of equipment and proceduralvariation should be addressed in the applicable specification.5.4 In accordance with the applicable specification, cush-ions may be pressurized without bursting to determine theirresistance to a fixed level of high internal pressure, or they maybe subjected

22、to increasing pressures to determine their ultimatebursting strength.6. Apparatus for Testing of Driver and PassengerCushions6.1 Plastic Liner Bags, with a combined bursting strength of3.5 kPa (0.5 psi) or less for use as optional bladders to aid inthe bursting of cushions whose fabric permeability

23、is too highto permit ultimate bursting strength testing without them.6.2 Patches or Plugs, to seal cushion vents, if cushionbursting is required and cushion overpressurization testingequipment does not provide the required air volume forbursting.6.3 Pressure Vessel, capable of being charged pneumati

24、callyfrom 0 to no less than 865 kPa (0 to no less than 125 psi) witha tolerance of 63 %, of sufficient volume to adequatelychallenge the volume of the cushion being tested, and equippedwith intake and outlet air lines and a quick-release solenoidvalve.6.4 Mounting Fixture, capable of retaining the c

25、ushionassembly by its attachment points without damaging thecushion material, in an orientation for free expansion of thecushion geometry, and with sufficient physical and noiseshielding for operator protection if the cushion overpressuriza-tion testing unit is not physically isolated in a separate

26、roomfrom the operator during actuation.6.5 Pressure Transducer and Pickup Tube, suitable formeasuring pressures inside the cushion from 0700 kPa (0100psi) with a tolerance of 63 %, mounted in a static or lowpressure area in the test fixture that does not interfere withcushion overpressurization.6.6

27、Data Acquisition System, suitable for recording theoutput of the pressure transducer versus elapsed time ofoverpressurization.6.6.1 Filter requirements, data sampling rate, transducerfrequency response, and amplifier frequency response shall besuch that minimal effect on accuracy of the data occurs.

28、Overall accuracy of the data acquisition system shall be within63%.6.7 Electrical Firing Pulse Source, suitable for actuating theinflation and for communicating with the data acquisitionsystem dependent on an electrical signal.6.8 High Speed Video System, suitable for recording thecushion geometry o

29、r mode of rupture during overpressurizationat 1000 or more frames per second, and capable of beingsynchronized precisely with a firing pulse (optional).6.9 Lighting System, suitable for high resolution photogra-phy (optional).7. Apparatus for Testing of Side Curtain and OtherCushions Designed to Mai

30、ntain Pressure7.1 Continuous Flow Compressed Air Source, capable ofsupplying from 0 to no less than 345 kPa (50 psi) andpreferably 690 kPa (100 psi) sufficient volume flow to ad-equately challenge the strength of the cushion being tested, andequipped with either manual or electrically controlled val

31、ve.7.2 Mounting Fixture, capable of retaining the cushionassembly by its attachment points without damaging thecushion material, in an orientation for free expansion of thecushion geometry, and with sufficient physical and noiseshielding for operator protection if the cushion overpressuriza-tion tes

32、ting unit is not physically isolated in a separate roomfrom the operator during actuation.7.3 Pressure Transducer and Pickup Tube, suitable formeasuring pressures inside the cushion from 0700 kPa (0100psi) with a tolerance of 61%.7.3.1 The pickup tube should be mounted coaxially throughthe fill nozz

33、le or opening and extend a minimum of 100 mmpast the cushion neck and into the inflatable space of thecushion, and not interfere with cushion expansion. The innerdiameter of the fill nozzle should be the largest inner diameterthat will fit into the cushion neck such that the coaxial pick-uptube will

34、 not significantly block the air flow into the cushion.7.4 Data Acquisition System, suitable for recording theoutput of the pressure transducer versus elapsed time ofoverpressurization. Overall accuracy of the data acquisitionsystem shall be within 61 %. Data Acquisition system can besynchronized ei

35、ther manually, electrically, or through softwarealgorithm with the cushion pressurization.D5807 1827.5 Manually or Electrically Operated Fill Valve, suitablefor actuating the inflation and for communicating with the dataacquisition system dependent on an electrical signal.7.6 High Speed Video System

36、, suitable for recording thecushion geometry or mode of rupture during overpressurizationat 1000 or more frames per second, and capable of beingsynchronized precisely with the fill valve opening (optional).7.7 Lighting System, suitable for high resolution photogra-phy (optional).8. Interferences8.1

37、The pressure transducer and/or pickup tube within themounting fixture must be mounted in a position that does notinterfere with the unfolding cushion.8.2 The pressure versus time data is subject to recordinganomalies and electronic noise. The data should be digitallyfiltered if needed to obtain the

38、underlying smooth pressurecurve prior to data analysis.9. Hazards9.1 Personnel conducting cushion overpressurization testingin the same room as the testing unit must be equipped with theappropriate safety equipment and safety training. Examples ofthe necessary safety equipment include, but are not l

39、imited to,ear protection, equipment shielding, and safety glasses. Properwritten safety procedures shall be provided to all test personnelfor compliance with standard industry practices. There shall becompliance to all applicable Occupational Safety and HealthAssociation (OSHA) standards. It is stro

40、ngly recommendedthat testing be done in a separate, sound dampened, roomequipped with ballistic glass and double paned viewing win-dows. Appropriate safeguards, procedures, or electricalinterlocks, or combinations thereof, should be in place toensure no personnel will be in the room with the cushion

41、 as itis being tested.10. Sampling10.1 Cushion overpressurization testing is a destructive testand therefore necessitates sampling procedures if used inconjunction with lot acceptance.10.2 For acceptance testing, the lot size is the quantity ofcushions sewn or produced on one production line in onep

42、roduction day.10.3 Lot SampleFor acceptance testing, take at randomthe number of cushions directed in an applicable cushionspecification or other agreement between purchaser and sup-plier. Consider cushions to be the primary sampling units.10.4 Each cushion in the lot sample is a test specimen.11. E

43、quipment Calibration11.1 For inflatable restraints, all test equipment used inaccordance with this practice shall be certified for calibrationannually by an independent agency or equipment manufacturerwhose results are traceable to the National Institute of Scienceand Technology (NIST) or other nati

44、onal standards laboratory.The test parameters of the equipment shall be tested within theoperating ranges covered in the cushion specification orequivalent document.12. Conditioning12.1 Conditioning of specimens for cushion overpressuriza-tion testing is conducted at the standard atmosphere for test

45、ingtextiles for at least 4 h prior to test. For testing of Side Curtainand other pressure holding cushions, conditioning is optional,as it is recognized that the compressed air source used to inflateand overpressurize the cushions being tested is not condi-tioned.13. Procedures for Testing of Driver

46、 and PassengerCushions13.1 Select and condition cushion specimens in accordancewith Section 10.13.2 If cushion bursting is intended and cushion overpres-surization testing equipment does not provide the required airvolume for bursting, seal the cushion vents with a plug or witha sewn fabric patch ma

47、de of the same material as the cushion.13.3 Mount the cushion specimen on the test fixture, ensur-ing that the retention mechanism does not damage the cushionmaterial, and that the pressure transducer and pickup tube donot interfere with the inflation of the cushion.13.4 Install a protective screen

48、around the test fixture, ifneeded, and if testing is not being done in an isolated room.13.5 Perform all system calibrations.13.6 Verify proper framing rate, camera settings, and light-ing intensity levels, if needed.13.7 Enter the test serial number into recording portions ofthe data acquisition an

49、d video systems.13.8 Confirm the pressure vessel is pressurized sufficientlyto evaluate the cushion under test.13.9 Turn on the warning light before arming the pressur-ization switch.13.10 Initiate the starting sequence and note the response ofthe data acquisition system to verify successful pressurization.13.11 Fill the cushion until it reaches the pre-set internalpressure or until it ruptures, as specified.13.12 Record test measurements such as maximum cushionpressure in kPa (psi), time to maximum cushion pressure inmilliseconds, or the location and nature of the cushion rupt