Research On The Improving Of Explosives Hazard Classification Procedures And Typical Test Methods

In this dissertation, the explosives hazard classification procedures of UN Orange Book and TB700-2 were studied. Aiming at the current problem that the propellant can not be exactly classified by the present hazard classification procedures, a new hazard classification procedure of propellant was put forward, namely, using UN gap test, extremely insensitive detonating substance (EIDS) gap test, actual size gap test and bonfire test to classify the propellants. The new explosives hazard classification procedure was formed, on the basis of incorporating the proposed procedures into the hazard classification procedure of UN Orange Book. And the test conditions and results criteria of related experimental methods were studied.The detonation pressure of booster charge, and the interface shock wave pressure between the booster charge and PMMA spacer of UN gap test, were obtained by managing gauges and graphing method. And the results show that the values of measured and calculated are basically the same. The output shock pressures of the booster charges of UN and EIDS gap tests, which are consist of Entoleter and A-IX-I respectively, were measured in the PMMA spacer with different thicknesses. According to the shock pressure attenuation law of booster charges in the PMMA spacer, the shock pressures of booster charges in UN and EIDS gap tests were 7GPa as the thickness of PMMA spacer are 19.2mm and 45.2mm respectively. The AUTODYN was used to simulate the attenuation process of the shock wave in the PMMA gap. The results of actual measurement and numerical simulation are consistent, namely, AUTODYN software can be used to predict the thickness of PMMA spacer in other sizes gap tests.The shockwave pressure distribution laws of the booster charges were studied by experiment and numerical simulation, and the results of numerical simulation were in accordance with the test results. According to the results, they can be used to determine the safe distance of gap test.In order to get the quantitative criterion of gap test, the average detonation velocity and continuous detonation velocity of two non-ideal explosives in the UN gap test were measured by electrometric method and continuous velocity probe. The detonation velocity measured by the continuous velocity probe method is in accordance with the traditional electrometric method, and the previous method can even give the true course of detonation development for non-ideal explosives. The continuous velocity probe was selected to study the continuous detonation velocity and detonation development of modified ANFO in the UN test. The results show that the continuous velocity probe can well reflect samples change process, i.e. the continuous detonation velocity of samples can be used as the quantitative criterion of gap test.Oxygen bomb calorimeter was used to measure the combustion heats of 9 samples, which include three propellants and six fireworks. The heat fluxes of these samples were measured and calculated by a radiometer and the estimation method respectively. The results show that, as the burning time is greater than 5s in the stable combustion process, the calculated heat flux is in accordance with the measured value; and as the burning time is not more than 5s, or violent effect appears in the combustion process, such as deflagration and explosion, measuring the heat flux by radiometer is prefered, because the ratio of radiant heat to combustion heat used in estimation method (0.33) is greater than the actual ratio, and it will lead to an abnormal calculated value.