1、Designation: D 5487 98 (Reapproved 2008)Standard Test Method forSimulated Drop of Loaded Containers by Shock Machines1This standard is issued under the fixed designation D 5487; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the y
2、ear of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the general procedures of usingshock machines to replicate the effects of vertical dro
3、ps ofloaded shipping containers, cylindrical containers, and bagsand sacks.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This s
4、tandard does not purport to address all 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 of regulatory limitations prior to use.2. Referenced Documents2.
5、1 ASTM Standards:2D 996 Terminology of Packaging and Distribution Environ-mentsD 999 Test Methods for Vibration Testing of ShippingContainersD 3332 Test Methods for Mechanical-Shock Fragility ofProducts, Using Shock MachinesD 4332 Practice for Conditioning Containers, Packages, orPackaging Component
6、s for TestingD 5276 Test Method for Drop Test of Loaded Containers byFree FallE 122 Practice for Calculating Sample Size to Estimate,With Specified Precision, the Average for a Characteristicof a Lot or Process3. Terminology3.1 General terms for packaging and distribution environ-ments are found in
7、Terminology D 996.3.2 Definitions of Terms Specific to This Standard:3.2.1 critical elementthe most fragile component of thetest specimen.33.2.2 shock pulse programmera device used to control theparameters of the shock pulse and shape of the pulse generatedby the shock test machine.3.2.3 shock test
8、machine drop heightthe distance throughwhich the carriage of the shock test machine free falls beforestriking the shock pulse programmer.3.2.4 velocitythe rate of change of position of a body in aspecified direction with respect to time, measured in inches persecond or metres per second.4. Significa
9、nce and Use4.1 Shipping containers and the interior packaging materialsare used to protect their contents from the hazards encounteredin handling, transportation, and storage. Shock is one of themore troublesome of these hazards. Free-fall drop testing,while easy to perform, often understresses the
10、test specimen bysubjecting it to drops which are not perpendicular to thedropping surface.NOTE 1For example, testing has shown that non-perpendicular drops,2 off perpendicularity, result in 8 % lower acceleration into the testspecimen resulting from the impact energy dispersing in several axes.44.1.
11、1 Controlled shock input by shock machines provides aconvenient method for evaluating the ability of shippingcontainers, interior packaging materials, and contents to with-stand shocks. Simulated free-fall drop testing of packagesystems, which have critical elements, has produced goodresults where t
12、he frequency of the shock pulse is at least threetimes that of the package systems natural frequency.4.2 As in most mechanical shock test procedures, fixturingof the package on the shock test machine may have significantinfluence on the test results. Typically, packages will be firmlyheld on the tab
13、le by securing some type of cross member(s)across the top of the package. Care should be taken that anypressure resulting from such fixturing should be minimal,particularly when the container being tested is corrugated orsome other similar material.1This test method is under the jurisdiction of ASTM
14、 Committee D10 onPackaging and is the direct responsibility of Subcommittee D10.22 on Physical TestMethods.Current edition approved April 1, 2008. Published May 2008. Originallyapproved in 1998. Last previous edition approved in 2002 as D 5487 98 (2002).2For referenced ASTM standards, visit the ASTM
15、 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.3Robert E. Newton, Fragility Assessment Theory and Test Procedures, U. NavalPostgraduate School, Monterey,
16、California.4Fiedler, Robert M. and Fanfu Li, A Study of the Effects of Impact Angles on theShock Levels Experienced by Packaged Products, MTS Systems Corporation. Onfile at ASTM. Request RR:D10-1008.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,
17、United States.4.2.1 In cases where low-acceleration, long-duration re-sponses are anticipated, any fixturing can potentially influencepackaged item response and can possibly alter any correlationbetween this test method and free-fall drop testing. Where suchcorrelation is desired, the package can be
18、 tested without itbeing fixed directly to the table. Note that in such circum-stances, the shipping container can vigorously rebound fromthe table and can, if not otherwise controlled, present a safetyproblem for operators. Fixing the shipping container to theshock machine table is most often recomm
19、ended for safety andconvenience, but accuracy and precision of this test methodshould not be compromised by such fixturing.NOTE 2A rigid package system with a natural frequency above 83 Hzrequires a shock pulse shorter than the 2-ms (nominal) duration currentlyavailable with many of todays shock mac
20、hines:fs5 1 cycle/ds3 2!fs5 1 cycle/0.002 3 2! 5 250 Hzfp5 fs/3fp5 250 Hz/3 5 83 Hzwhere:ds= shock pulse duration, s,fs= shock pulse frequency, Hz, andfp= package system frequency, which may be determined by TestMethods D 999.Similarly, a shock machine using an input shock pulse duration of 3 mswoul
21、d only be effective with package system frequencies below 56 Hz.5. Apparatus5.1 Shock Test Machine:5.1.1 The machine shall consist of a flat horizontal testsurface (carriage) of sufficient strength and rigidity to remainflat and horizontal under stress developed during the test. Thetest surface shal
22、l be guided to fall vertically without rotation ortranslation in other directions.5.1.2 The machine shall incorporate sufficient carriage dropheight to produce shock pulses at the carriage as described in9.1. Drop height control shall be sufficient to control velocitychange reproducibility on the ta
23、ble of 65%.5.1.3 Means shall be provided to prevent secondary shocksby stopping the motion of the carriage after impact.5.2 Instrumentation:5.2.1 Acceleration An accelerometer, a signal condi-tioner, and a data storage apparatus are required to recordvelocity change histories. The accelerometer shal
24、l be rigidlyattached to the carriage. The instrumentation system shall havesufficient response to permit measurements to at least 1000 Hz.5.2.2 AccuracyReading to be within 65 % of the actualvalue.5.2.3 Cross-Axis SensitivityLess than 5 % of the actualvalue.5.2.4 VelocityInstrumentation to measure t
25、he shock ta-bles velocity change is required. This may be a device whichelectronically integrates the area under the shock pulse wave-form. Alternatively, it can be measured by a photodiode typedevice which measures the shock table impact and reboundvelocity. Calculation which assumes the shock puls
26、e to be aperfect geometric figure usually is grossly inaccurate andshould not be used.6. Sampling, Test Specimens, and Test Units6.1 The sampling and the number of test specimens dependon the specific purposes and needs of the testing. Sample sizedetermination in accordance with Practice E 122 or ot
27、herestablished statistical procedures is recommended.6.2 When the protective ability of the package is to beevaluated, pack the package with the actual contents for whichit was designed.6.2.1 Where the use of actual contents is prohibitive becauseof excessive cost or danger, a “dummy” load simulatin
28、g thecontents with respect to dimensions, center of gravity, momentof inertia, product characteristics such as viscosity, etc., may beused with accelerometers or other indicating mechanisms.6.2.2 Regardless of which procedure is used, close or strapthe container, or both, in the same manner that wil
29、l be used inpreparing it for shipment.6.3 The procedure for identification of the members of thecontainer shall be in accordance with Test Method D 5276.7. Calibration and Standardization7.1 The accuracy of the test equipment must be verified toensure reliable test data.7.2 Verification of calibrati
30、ons must be performed on aregular basis to ensure compliance with all accuracy require-ments established in Section 5. Typically, system verification isperformed minimally on an annual basis.7.2.1 In no case shall the time interval between verificationof calibration exceed 18 months.7.2.2 Regardless
31、 of the time interval since the last verifica-tion, testing machines shall be verified immediately afterfunctional repairs, relocation, and whenever there is reason todoubt the accuracy.8. Conditioning8.1 It is recommended that atmospheres for conditioning beselected from those in Practice D 4332. U
32、nless otherwisespecified, fiberboard and other paperboard containers shall bepreconditioned and conditioned in accordance with the stan-dard atmosphere specified in Practice D 4332 and tested in thatatmosphere where practical.8.1.1 If 8.1 is not practical, tests should be conducted within15 min of r
33、emoval from the conditioning atmosphere.9. Procedure9.1 Set up the shock test machine to produce a haversine orhalf sine pulse waveform with a pulse duration not longer than3ms(Note 2). The measured velocity change(impact + rebound) of the shock machine table should beequivalent to the impact veloci
34、ty for the chosen free-fall dropheight, as calculated using the following formulas:DVT5 Viwhere:Vi=2gh ,DVT= measured table velocity change,Vi= calculated free fall drop impact velocity,g = acceleration due to gravity, 386.4 in./s2(9.806m/s2), andD 5487 98 (2008)2h = equivalent free fall drop height
35、, in. (m).9.1.1 When rebounding-type shock pulse programmers areused, the shock machine drop height is usually substantiallydifferent from the equivalent free-fall drop height. Provisionshall be made for determining the velocity change of the shockmachine table. The velocity change may be determined
36、 byusing a photodiode type velocity meter which measures shockmachine table velocity change (impact plus rebound). Anelectronic device which measures acceleration versus time mayalso be used to record the shock wave pulse. Integrating thearea under the curve, either electronically or by other meansw
37、ill result in the total velocity change as a result of the impact(see Fig. 1 in Test Methods D 3332).9.2 Method AUnrestrained Test:9.2.1 Identify the shipping container members in accor-dance with Test Method D 5276.9.2.2 Place the shipping container on the center of the shockmachine table. Raise th
38、e table to the predetermined machinedrop height, and release the table. Movement of the specimenshould be controlled so that a second impact is prevented.Motorcycle bunge cord netting has been successfully used toprevent test specimens from rebounding from the shockmachine table during impact.NOTE 3
39、Warning: Use caution to prevent injury to the operator anddamage to the unit. This test method should not be used if the shippingcontainer is large, bulky, or highly resilient.9.2.3 Perform one shock test.9.2.4 Examine or functionally test the product and shippingcontainer to determine if damage has
40、 occurred.9.2.5 Continue shock testing until the required membershave been impacted.9.3 Method BRestrained Test Method:9.3.1 Identify the shipping container faces in accordancewith Test Method D 5276.9.3.2 Place the shipping container on the center of the shockmachine table. Restrain movement of the
41、 loaded container sothat the shock pulse is directly transmitted to the test specimen.Raise the table to the predetermined machine drop height andrelease the table.9.3.3 Perform one shock test.9.3.4 Examine or functionally test the product and containerto determine if damage has occurred.9.3.5 Conti
42、nue shock testing until the required members inaccordance with Test Method D 5276 have been impacted.10. Report10.1 Report the following information:10.1.1 Method, if any, of conditioning the shipping con-tainer, the moisture content of the wood, plywood, or fiber-board, if determined, and the resul
43、ts of supplementary tests ofthe materials from which the specimen is made.10.1.2 The dimensions of the container under test:10.1.2.1 Complete structural specifications;10.1.2.2 Materials used;10.1.2.3 Description and specifications for blocking andcushioning, if used;10.1.2.4 Spacing, size, and kind
44、 of fasteners;10.1.2.5 Method of closing and strapping, if any, and10.1.2.6 Tare and gross masses.10.1.3 Description of the contents of the shipping containerunder test.10.1.4 Description of the apparatus and special instrumen-tation, if used.10.1.5 Description of the prescribed test sequence, ident
45、ify-ing the member being impacted for each drop (for example, thecorner formed by the manufacturers joint, if applicable, andthe number of drops).10.1.6 Velocity change, free-fall drop height, input shockduration, and the response natural frequency, determined inaccordance with Test Methods D 999, o
46、r its shock duration.10.1.7 Number of specimens tested per sample.10.1.8 Detailed record of test on each specimen, includingdamage to the shipping container and contents, together withany other observation which may assist in correctly interpret-ing the results or aids in improving the design of the
47、 containeror the method of packing, blocking, or bracing.10.1.9 Dates of last calibration of the test equipment andinstrumentation.10.1.10 Statement listing any deviations from this testmethod.10.1.11 Complete description of any fixturing used forpositioning corner and edge drops.11. Precision and B
48、ias11.1 PrecisionThe within-laboratory or repeatability stan-dard deviation is largely dependent on the particular item beingtested. A research report5describes an interlaboratory testprogram of three types of items (in packages) for a criticalvelocity shock test. The repeatability values standard d
49、evia-tions were 6.7, 14.7, and 21.5 in./s (0.17, 0.37, and 0.55 m/s)with corresponding coefficients of variation of 5.7, 7.7, and12.4 %. Other items may have more or less variability. Thebetween-laboratory or reproducibility standard deviation was5.7 in./s (0.15 m/s) or a coefficient of variation of 3.2 %.11.2 BiasNo justifiable statement can be made on the biasof this test method since a true value cannot be established byan accepted referee method.12. Keywords12.1 critical element; drop test; packaging container; shock;shock machine; velocity5R. L. Sheehan, I
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