ASTM D3332-99(2010)
(Test Method)Standard Test Methods for Mechanical-Shock Fragility of Products, Using Shock Machines
Standard Test Methods for Mechanical-Shock Fragility of Products, Using Shock Machines
SIGNIFICANCE AND USE
These test methods are intended to provide the user with data on product shock fragility that can be used in choosing optimum-cushioning materials for shipping containers or for product design modification.
SCOPE
1.1 These test methods cover determination of the shock fragility of products. This fragility information may be used in designing shipping containers for transporting the products. It may also be used to improve product ruggedness. Unit or consumer packages, which are transported within an outer container, are considered to be the product for the purposes of these test methods. Two test methods are outlined, as follows:
1.1.1 Test Method A is used first, to determine the product's critical velocity change.
1.1.2 Test Method B is used second, to determine the product's critical acceleration.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific precautionary statements, see Section 6.
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D3332 − 99(Reapproved 2010)
Standard Test Methods for
Mechanical-Shock Fragility of Products, Using Shock
Machines
This standard is issued under the fixed designation D3332; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Packaging Components for Testing
D5112 Test Method for Vibration (Horizontal Linear Mo-
1.1 These test methods cover determination of the shock
tion) Test of Products
fragility of products. This fragility information may be used in
E122 Practice for Calculating Sample Size to Estimate,With
designing shipping containers for transporting the products. It
Specified Precision, the Average for a Characteristic of a
may also be used to improve product ruggedness. Unit or
Lot or Process
consumer packages, which are transported within an outer
E680 Test Method for Drop Weight Impact Sensitivity of
container, are considered to be the product for the purposes of
Solid-Phase Hazardous Materials
these test methods. Two test methods are outlined, as follows:
1.1.1 Test MethodAis used first, to determine the product’s
3. Terminology
critical velocity change.
1.1.2 Test Method B is used second, to determine the
3.1 Definitions—General definitions for packing and distri-
product’s critical acceleration.
bution are found in Terminology D996.
1.2 The values stated in inch-pound units are to be regarded
3.2 Definitions of Terms Specific to This Standard:
as standard. The values given in parentheses are mathematical
2 2
3.2.1 acceleration of gravity (g)—386.1 in./s (9.806 m/s ).
conversions to SI units that are provided for information only
3.2.2 critical acceleration (A )—the maximum-faired accel-
and are not considered standard.
c
eration level for a minimum velocity change of 1.57 ∆V (see
c
1.3 This standard does not purport to address all of the
9.3), above which product failure (or damage) occurs. A
safety concerns, if any, associated with its use. It is the
product usually has a different critical acceleration for each
responsibility of the user of this standard to establish appro-
direction in which it is tested.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. For specific
3.2.3 critical velocity change (V )—the velocity change (see
c
precautionary statements, see Section 6.
9.2) below which product failure is unaffected by shock-pulse
maximum-faired acceleration or waveform. A product usually
2. Referenced Documents
has a different critical velocity change for each direction in
2.1 ASTM Standards: which it is tested.
D996 Terminology of Packaging and Distribution Environ-
3.2.4 damage—product failure that occurs during a shock
ments
test. Damage can render the product unacceptable because it
D2463 Test Method for Drop Impact Resistance of Blow-
becomes inoperable or fails to meet performance specifications
Molded Thermoplastic Containers
when its appearance is unacceptably altered, or some combi-
D3580 Test Methods for Vibration (Vertical Linear Motion)
nation of these failure modes occurs.
Test of Products
3.2.5 damage boundary—See Annex A3.
D4332 Practice for Conditioning Containers, Packages, or
3.2.6 fairing—The graphical smoothing of the amplitude of
a recorded pulse still containing high frequency components
These test methods are under the jurisdiction of ASTM Committee D10 on
even though electronic filtering may have been performed.
Packaging and are the direct responsibility of Subcommittee D10.13 on Interior
Packaging.
This amplitude is used to evaluate the basic recorded pulse
Current edition approved Jan. 1, 2010. Published January 2010. Originally
features with respect to the specified pulse. (see Figs.A1.1 and
approved in 1988. Last previous edition approved in 2004 as D3332 – 99(2004).
A2.1)
DOI: 10.1520/D3332-99R10.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3.2.7 shock pulse programmer—a device used to control the
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
parameters of the acceleration versus time shock pulse gener-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. ated by a shock test machine.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D3332 − 99 (2010)
3.2.8 shock test machine drop height—the distance through therefore remain alert to potential hazards and take necessary
which the carriage of the shock test machine falls before safetyprecautions.Thetestareashouldbeclearedpriortoeach
striking the shock pulse programmer. impact. The testing of hazardous material or products may
require special precautions that must be observed. Safety
4. Significance and Use
equipment may be required, and its use must be understood
4.1 These test methods are intended to provide the user with
before starting the test.
data on product shock fragility that can be used in choosing
7. Sampling
optimum-cushioning materials for shipping containers or for
product design modification.
7.1 Sampling procedures and the number of test specimens
depend on the specific purposes and needs of the testing.
5. Apparatus
Sample size determination based on Practice E122 or other
5.1 Shock Test Machine:
established statistical procedures is recommended.
5.1.1 The machine shall consist of a flat horizontal test
surface (carriage) of sufficient strength and rigidity to remain 8. Conditioning
flat and horizontal under the stresses developed during the test.
8.1 If temperature and humidity conditioning is required for
The test surface shall be guided to fall vertically without
the product being tested, refer to Practice D4332 for standard
rotation or translation in other directions.
conditioning procedures. Unless otherwise specified, conduct
5.1.2 The machine shall incorporate sufficient carriage drop
all tests with the same conditions prevailing.
height to produce the shock pulses given in 9.2 and 9.3. Drop
height control shall be provided to permit reproducibility 9. Procedure
within 60.25 in. (66 mm).
9.1 Mount the product to be tested on the carriage of the
5.1.3 The machine shall be equipped to produce shock
shock test machine. The product should be supported by a
pulses at the carriage as specified in 9.2 and 9.3.
fixture similar in shape and configuration to the cushion that
5.1.4 Means shall be provided to arrest the motion of the
will support the product in its shipping container. The fixture
carriage after impact to prevent secondary shock.
should be as rigid as possible so as not to distort the shock
5.2 Instrumentation:
pulse imparted to the product. Fasten the fixture and product
5.2.1 Acceleration—An accelerometer, signal conditioner, securely to the carriage so that it will not leave the surface of
and data storage apparatus are required to record acceleration-
the carriage during the shock test.
time histories. The accelerometer shall be attached rigidly to
NOTE 1—The points at which the fixture supports the product are very
the base structure of the product or to the fixture, at or near a
important because the dynamic response of the product is influenced
point at which the fixture is fastened to the carriage. If the
strongly by the location of these support points
fixture is sufficiently rigid to not distort the shock pulse NOTE 2—If the orientation of the product can change during handling
impacts, a test may be required for each of the directions in which the
imparted to the product, the accelerometer may be mounted on
input shock can occur. Multidirectional tests are recommended since most
the carriage. In some cases, when a product contains heavy
products have different fragilities in different orientations.
resiliently supported masses that will distort the shock pulses
9.2 Test Method A—Critical Velocity Change Shock Test:
severely, it may be necessary to precalibrate the shock ma-
9.2.1 Scope—This test method is used to determine the
chine.Theaccelerometerisfastenedtothecarriageinthiscase,
critical velocity change (V ) portion of the damage boundary
c
and a rigid mass weighing the same as the product is subjected
plot of a product.
to a series of shock pulses. The instrumentation system shall
9.2.1.1 To ensure that the components of a product only
have sufficient response to permit measurements in the follow-
respond to the velocity change of the pulse, a shock pulse
ing ranges.
having any waveform and a duration (T ) not longer than 3 ms
p
5.2.1.1 Test Method A—5 Hz or less to at least 1000 Hz.
should be used to perform this test. Pulse durations as short as
5.2.1.2 Test Method B—1 Hz or less to at least 330 Hz.
0.5 ms may be required when testing small, very rigid products
5.2.1.3 Accuracy—Reading to be within 65 % of the actual
(see Note 3). Shock pulse waveform is not limited since the
value.
critical velocity portion of the damage boundary is unaffected
5.2.1.4 Cross-Axis Sensitivity—Less than 5 % of the actual
by shock pulse shape. Since they are relatively easy to control,
value.
shock pulses having a half sine shock waveform are normally
5.2.2 Velocity—Instrumentation to measure the velocity
used.
changeoftheshocktableisrequired.Thismaybeadevicethat
integrates the area electronically under the shock pulse wave-
NOTE 3—In general: T ≤ 167 / f
p c
form. Alternatively, it can be measured by photodiode-type
where:
devices that measure shock table impact and rebound velocity.
T = maximum shock test machine pulse duration in ms, and
p
Calculation that assumes the shock pulse to be a perfect
f = component natural frequency in Hz.
c
geometricfigureisusuallygrosslyinaccurateandshouldnotbe
For example, a component of a product with a natural frequency below
used.
56 Hz can be effectively tested on a shock machine witha3ms duration
pulse. If the component natural frequency is higher, the pulse duration
6. Precautions
must be shorter. A 2 ms duration pulse can be used on a component with
a natural frequency up to 83 Hz.
6.1 These test methods may produce severe mechanical
responses in the test specimen. Operating personnel must 9.2.2 Procedure:
D3332 − 99 (2010)
9.2.2.1 Set the shock test machine so that the shock pulse 9.3.2.4 Examine or functionally test the product, or do both,
produced has a velocity change below the anticipated critical to determine whether damage due to shock has occurred.
velocity change of the product. 9.3.2.5 If no damage has occurred, set the shock test
9.2.2.2 Perform one shock test. machine for a higher maximum-faired acceleration level. Be
certain that the velocity change of subsequent shock pulses is
9.2.2.3 Examine or functionally test the product, or do both,
maintained at or above the level determined in 9.3.2.1.Accept-
to determine whether damage due to shock has occurred.
able increment size is influenced strongly by the product being
9.2.2.4 If no damage has occurred, set the shock test
tested.Forexample,anincrementof5gmaybeappropriatefor
machine for a higher velocity change and repeat the shock test.
most products but unacceptable for high-value products.
Acceptableincrementsizeisinfluencedstronglybytheproduct
being tested. For example, an increment of 5 in./s (0.13 m/s)
NOTE4—Seeshockmachinemanufacturerrecommendationsforsetting
may be appropriate for most products but unacceptable for
acceleration levels because this procedure is specific to the type of
high-value products. programmer.
9.2.2.5 Repeat 9.2.2.2 – 9.2.2.4, with incrementally increas-
9.3.2.6 Repeat 9.3.2.2 – 9.3.2.5, with incrementally increas-
ing velocity change, until product damage occurs.This point is
ing maximum-faired acceleration, until product damage oc-
shown as Test No. 7 in Fig. A3.1.
curs.This point is shown asTest No. 14 in Fig.A3.1. Common
9.2.2.6 Common practice is to define the critical velocity
practice is to define the critical acceleration (A)asthe
c
change(V )asthemidpointbetweenthelastsuccessfultestand
c midpoint between the last successful test and the test that
the test that produced failure. Depending on the purpose of the
produced failure. Depending on the purpose of the test, use of
test, use of the last successful test point before failure may be
the last successful test point before failure may be considered
considered as a more conservative estimate of (V ).
as a more conservative estimate of (A ).
c
c
9.3 Test Method B—Critical Acceleration Shock Test:
10. Report
9.3.1 Scope—This test method is used to determine the
critical acceleration (A ) portion of the damage boundary plot
10.1 Report the following information:
c
of a product.
10.1.1 Reference to these test methods, noting any devia-
9.3.1.1 Whenthecriticalaccelerationofaproductisknown,
tions from the test method.
package cushioning materials can be chosen to protect it.
10.1.2 Complete identification of the product being tested,
9.3.1.2 If no cushioning materials are to be used in the
including type, manufacturer’s code numbers, general descrip-
package, it may be unnecessary to perform this test. Only the tion of configuration, and its pretest condition.
critical velocity change test may suffice in this case. 10.1.3 Method of mounting the product on the carriage of
9.3.1.3 Trapezoidal shock pulses are normally used to the shock test machine.
10.1.4 Type of instrumentation used and critical settings
perform this test. Although a true square wave shock pulse is
most desirable in theory, it is not possible to obtain infinitely thereof.
short rise and fall times. On the basis of much testing 10.1.5 Recordings of the shock pulses that caused product
experience, it has been determined that rise and fall times (see damage.
Fig.A2.1) of 1.8 ms, or less, are required. Longer rise and fall 10.1.6 Record of shock test machine drop height for each
times cause the critical acceleration line of the damage shock pulse that caused product damage.
boundary curve to deviate from the horizontal, introducing 10.1.7 Record of damage, including a photograph of prod-
errors into the test results. For the same reason, waveforms uct damage, if visible.
havingfairedshapesthatarenottrapezoidalshouldnotbeused 10.1.8 Record of waveform, maximum-faired acceleration,
for this test.Their use would cause the critical acceleration line pulse duration, and velocity change of the shock pulses.
of the damage boundary curve to vary widely as a function of 10.1.9 Record of conditioning used.
velocity change. For example, if a half sine shock pulse 10.1.10 Plots of damage boundaries of the product.
w
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