Performance Product Tests
1. Strength Test :
This strength of the detonator is evaluated by Lead Plate Test and Sand Bomb Test. These tests are indirect measure of the ability of detonators to initiate high explosives.
In Lead Plate Test, a square 3cm X3cm lead plate is used. The hole made in the lead plate by the detonator will determine the strength of detonator.
In Sand Bomb test, a preselected sand is subjected to the firing of the detonator. The amount of sand crushed in the firing will determine the strength of the detonator.
2. Series Firing :
TThis test is a measure of the firing ability of Electric Detonators, when connected in series and minimum firing current of 1.2 amperes DC is applied. All Electric Detonators are subjected to this test.
3. Firing Impulse Test :
This test is related to the fuse head and is a measure of the energy required to setoff a fusehead. It is expressed in milliwatt seconds per ohm. Higher the impulse level the greater is the insensitivity of the fusehead for firing currents and resisitant to leakage currents.
4. “No fire” current test :
This test is a measure of the ability of the detonators for not getting initiated when the prescribed level of current is passed through if for a specified time. It is a measure of safety against stray currents, which can initiate accidentally the fusehead and thus the detonator.
This test is done on all batches of fuseheads manufactured for use in Electric Detonators.
5.Under water pressure Test :
This test measures the ability of the detonators to get initiated even after exposure to water pressure. This will specify whether the detonators can be used in watery boreholes and or for underwater blasting applications.
This test is done on all types of detonators.
6.Buxton Test :
This test measures the fitness of the detonator for use in gassy mines. This test is carried out in special steel chambers in an atmosphere of 9% methane –air mixture.
This test applies to detonators required for use in underground gassy mines. Instantaneous Copper Electric Detonators and Super coal delay detonators are subjected to this test to evaluate their safety in gassy underground mines.
7.Continuity of Electrical Circuit of the detonators :
This test is being carried out to ensure the reliability of the fusehead. Eqach fusehead is tested for its continuity before crimping, during crimping and after crimping to the detonator shell. This is a routine test done to ensure continuity of electrical circuit for large hook-up of detonators. All electrical detonators are subjected to this test during series firing test also.
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