Testing method of packaging cushioning material vibration transmission

Add Time：2017/2/16    Clicks：1984

1 Scope
This standard specifies the test equipment package cushioning material vibration transmission characteristic test, the test samples, test procedures and test reports.
This standard applies to the assessment of the role of packaging in the sinusoidal vibration transfer (isolation) and the properties of the contents of the package protection capability with vibration damping material.
This standard applies to nonlinear elastic cushioning material.

2 Normative references
        The following documents contain provisions which, through reference in this standard and become the standard terms. For dated reference documents, all subsequent amendments (not including errata content) or revisions do not apply to this standard, however, encourage the possibility of applying the most recent editions of the study according to the parties to the agreement . For undated reference documents, the latest versions apply to this standard.
GB / T 4122.1 Packaging - Terminology - Part 1: Basic
GB / T 4857. 2 Basic tests for transport packages - Part 2: Temperature and humidity adjustment process (GB / T 4857. 2-2005, ISO 2233: 2000, MOD)

3 Terms
GB / T 4122.1 and established the following terms and definitions apply to this standard.

3.1
Acceleration transmissibility acceleration transmission rate
Acceleration acceleration ratio shaker table of the mass.

3.2
Vibration transmissibility - frequency curve vibration transmission rate -frequency curve
In the course of the test vibration table vibration frequency as abscissa, an acceleration test was formed during the transfer ordinate, plotted curve.

4 Test principle
        The tests conducted by mass, cushioning materials, fixtures and constitute a vibration shaker system to simulate the package buffer material under sinusoidal vibration effect (hereinafter referred to as the test sample) for vibration absorption, transfer characteristics. Test record acceleration values and the vibration state mass vibrating table, and expressed as the vibration transmissibility - frequency characteristic curve.

5 Test Equipment
5.1 shaker
        Shaking table should have a sufficiently large size, sufficient strength, rigidity and load carrying capacity. The structure should be able to guarantee the vibration shaker table
Maintain the level of the state, its lowest resonance frequency should be higher than the maximum test frequency. Shaking table should be flat, and the maximum angle between the level change is 0.3 °.
5.2 Fixtures
5.2.1 The fixture should have done to ensure the quality of the block rigidity and strength of vertical vibration, the structure see Appendix A. Friction between the fixture and the mass should not affect the vibration response of the mass.
Cover surface 5.2.2 fixture should be smooth, hard, on the area under the bottom should be more than 200mmx200mm, and can exert static pressure 0. 7kPa on the upper part of the test sample mass.
5.3 mass
5.3. 1 mass should be smooth surface structure of the histogram, the area under the bottom should be more than 200mmx200mm, the quality can be adjusted.
Mass of hardwood or metal, the geometric center of the mass shall be provided with an acceleration sensor installed cavity.
5.3.2 mass should ensure the normal stiffness and strength tests, the mass should be possible to choose a single piece, such as the use of a plurality of mass should be tightened in order to avoid generating no fixed between mass collide with each other, thus affecting the test results.
5.4 Test System
Test system includes an acceleration sensor, amplifier, display or recording devices. Test systems should have enough frequency response within the measurement range, accuracy of the test system should be within ± 5%.

6 test samples
6.1 Sampling
Test samples should be placed above the finished extract 24h, when it can not meet the size requirements, allows the production conditions
Under the same conditions specially manufactured test sample.
6.2 Dimensions
Test samples straight regular cube shape, the area under the bottom of 200mmx200mm respectively. Thickness of the test specimen as required
To select.
6.3 Number of
The number of test samples is generally based on the accuracy of the test sample material and test results required to select. A number of test samples shall be not less than three.
6.4 Measurement
6.4.1 Length and width
Respectively, along the length and width directions of the test sample with a minimum scale is not greater than 0. 05 mm at both ends of the gaging and size of the intermediate three positions, respectively, an average value, and is accurate to 0.1 mm.
6.4.2 Thickness
Place a flat rigid plates on the upper surface of the test sample, the test sample being 0.20 kPa ± 0.02 kPa compressive load. After 30 s under a load state with the most minimum scale is not greater than 0. 05mm thickness gage measuring four corners, an average value, and accurate to 0.1mm.
6.4.3 Density
A. with a sense of the amount of 0.01g or more weighing scales mass of the test sample and records the measured value;
B. density test sample calculation shown in Equation (1)


Where:
P test sample density in grams per cubic millimeter (g / mm3) 5
m test sample weight in grams (g);
Li test sample length in millimeters (mm);
U-- width of the test sample, in millimeters (mm);
T-- test sample thickness in millimeters (mm).

7 Test Procedure
7.1 Pretreatment of test samples
Before the test, according to GB / T 4857.2 choose one of the conditions of the test sample pretreatment 24h or more.
Temperature and humidity conditions during test 7.2
The test shall be performed under the same pretreatment temperature and humidity conditions. If you can not reach the same conditions, it should be carried out under the same conditions as much as possible.
7.3 Test procedure
7.3.1 respectively, mass and acceleration vibration sensor mounted on the mounting.
7.3.2 adjust the quality of the mass to apply static pressure required for the test samples.
7.3.3 two test samples were placed in the upper and lower surfaces of the mass.
7.3.4 The cover fixing device is pressed against the upper portion of the test sample mass, and properly reinforced. Usually the upper portion of the test sample should be subject to a static pressure of 0.7 kPa. Fixtures, test samples, the vertical position of the mass center of gravity should be as close to the geometric center of the actual shaker platform. Test should be avoided due to the mass of the test sample separation occurs resulting in distortion of the test data.
NOTE: For a plastic test sample, may take appropriate measures to eliminate the influence of plastic deformation of the test sample for the test.
7.3.5 Test sweep under the following conditions:
. A frequency range: 3Hz frequency began to increase, and passed through the resonance point of the system, until the vibration transmissibility is reduced to about 0.2 so far;
. B sweep rate: one-half octave or one octave per minute per minute;
c .. acceleration: 5 m / s2.
7.3.6 During the test, recording acceleration values shaker table and on the mass and the corresponding vibration frequency.
7.3.7 Calculation of acceleration transmissibility.
7.3.8 transfer rate ordinate acceleration, vibration frequency of the vibration table as abscissa, plotted vibration transmissibility - frequency curve.

8 Test Report
      The test report shall include the following:
      . A detailed description of the test sample material such as the name, type, shape, size, density, plant, brands, said the factory of the like;
      . B number of test samples;
      . C pretreatment conditions of the test sample;
      . D When the test temperature and humidity conditions;
      . E For a description of test equipment;
      . F acceleration time history of a sample of each test;
      . G maximum acceleration a static stress curve, and marked drop Gao degree when test;
      . H Dynamic test sample compressive residual strain;
      I. Description Test methods used differ from these standards;
      . J Other detailed records and notes;
      k. test date, test personnel to sign the test unit seal.