SN/T 5274-2020Fireworks bomb launch dynamic pressure test sensor method (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard was proposed and managed by the General Administration of Customs of the People's Republic of China.

Drafting organization of this standard. Changsha Customs of the People's Republic of China.

1 Scope

This standard specifies the equipment, materials, test procedures and data processing required for the sensor method to test the dynamic pressure in the cylinder when the firework bomb is launched.

This standard is applicable to the test of the peak pressure in the barrel and the launch impulse when the firework shells of 50 mm~25 mm are launched.

2 Normative references

The following documents are indispensable for the application of this document. For dated reference documents, only the dated version applies to this article Pieces. For undated reference documents, the latest version (including all amendments) is applicable to this document.

GB 19594 Fireworks and Firecrackers JJG 59 Piston Pressure Gauge

3 Terms and definitions

The following terms and definitions defined in GB 19594 apply to this document.

Launch pressure

When the fireworks is set off, the maximum value of the pressure change in the launching cylinder is expressed in megapascals (MPa).

Ascent along time

The time interval during which the pressure in the launching barrel increases from 1% of the launch pressure value to the maximum value when the fireworks is set off.

Descent along time

When the fireworks is set off, the time interval between the change in pressure in the launch barrel from the maximum value to 1% of the launch pressure value.

Launch impulse

The gas produced when the firework propellant burns acts on the impulse of the launching tube.

4 Equipment and materials

5 Test preparation

Use piston pressure gauge (4.2) and pressure acquisition system to statically calibrate the test pressure sensor.

6 Test procedure

6.1 Measure the projectile diameter of the sample with a caliper (4.3), and select a suitable test launch tube according to the measured value according to the requirements of Table 2.Bullet diameter does not meet table 2 Samples with deviations specified in the above cannot be used for subsequent testing. Measure and record the inner diameter of the launch tube.

6.2 Erect the launch tube with the pressure sensor upright and keep it firmly. Put the sample to be tested into the launch tube.

6.3 Set the sampling frequency, sampling duration, trigger mode and trigger level of the pressure acquisition system according to the specifications of the test sample.

6.4 The sample is ignited, and the pressure acquisition system records the pressure change curve measured by the pressure sensor over time.

Use the data acquisition system to record the peak pressure (Pp) of the pressure curve and the rising and falling time of the pressure during launch.

6.5 Repeat the operations described in 6.1~6.4.For each size of firework bombs, at least 5 tests are carried out.

7 Data processing