The Small Gap Test Using Underwater Explosion

The shock sesitivity of highly sensitive explosive materials. 

A pool 3 m in diameter and 2 m deep is neccesary for the test. Fig.3.125 shows the apparatus. Measuring instruments are the same as in the variable initiation test Sample bottles and inner tubes are also the same as those used in the variable initiation test. 

1 Measuring the first pulsation period of No.O cap within an inner tube A No.O cap inserted into a plastic inner tube is sunk to a depth of 1 m deep and detonated. The first pulsation period of the bubble is measured by a pressure sensor placed 1 m away from the sample. 

The calculation of bubble energies (E b) is done the same way as in the variable initiation test. Curves describing the strength of the explosions are prepared by plotting 

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