Drop weight test

Reactivity (instability) information Acceleration rate calorimetry Differential thermal analysis (DTA) Impact test Thermal stability Lead block test Explosion propagation with detonation Drop weight test Thermal decomposition test Influence test Self-acceleration temperature Card gap test (under confinement) JANAE Critical diameter Pyrophoricity... 

Drop weight test Thermal decomposition test Influence test... 

Very shock sensitive explodes in drop-weight test at 11 kg-cm. 

Drop weight test A weight is dropped on a sample in a metal cup. The test measures the susceptibility of a chemical to decompose explosively when subjected to impact. This test should be applied to any materials known or suspected to contain unstable atomic groupings. 

A relatively unstable material, the energetic decomposition of which can be initiated by merely the input of mechanical energy at normal ambient conditions. Materials are considered as shock sensitive if they are more easily initiated than dinitrobenzene in a standard drop-weight test. 

The product from the distillation was analyzed by drop weight testing and differential scanning calorimetry (DSC). The drop weight test indicated that the product was not shock sensitive. By DSC, there was a 400 cal/g release of energy which initiated at 135°C. The pot residue showed a slow release of energy which was estimated to be ca. 100 cal/g and initiated at 150°C. 

In tests of materials saturated with liq oxygen and subjected to 71-75 lb drop weight tests, the following were found acceptable (one de-tonation/40 impacts or none/20) fluorocarbon oils greases, graphite, halogenated biphenyl molybdenum disulfide lubricants, polyethylene... 

The shock sensitivity of materials are also frequently evaluated in a drop weight test. A variety of drop weight testers have been developed, but the standard device used to evaluate the sensitivity of liquid propellants is test No. 4 of the Joint Army-Navy-Air Force Panel on Liquid Propellants (2). A sample of material (usually less than 0.1 gram) is confined in an enclosed volume, and a calibrated weight is allowed to... 

H) NDRC Summary Tech Rept of Div 8, Vol 1 (1946), 38—41 (Sensitiveness drop-weight tests)... 

Trauzl Block and Drop Weight Test Values for Liquid Reaction Intermediates. U 22... 

Shock sensitive materials react exothermally when subject to a pressure impulse. The impulse may come from a hammer-like blow, such as used in the standard drop-weight test, or a compression, such as might be experienced in a deadheaded plant compressor or valve slamming shut. Normally, shock sensitivity increases with an increase in temperature. Materials that do not show an exotherm on the DSC are seldom shock sensitive. 

TABLE 2. Comparison of Explosivity of Nitro-dur Scrubber Charcoal with Known Explosives Using the JANAF Drop Weight Test... 

Falling Weight Test. Same as Drop Weight Test. See Impact Sensitivity or Shock Sensitivity Test in Vol 1, p XVII. See also list of Refs on Impact in Vol 4, p D391-R... 

Liquid Propellant Test Methods, Test No. 4, Drop-Weight Test, Chemical Propulsion Information Agency, The Johns Hopkins University Applied Laboratory, Silver Spring, Md., 1964. 

Standard tests are utilized early in the evaluation phase to evaluate flammability, ignition and explosive characteristics. These include differential thermal analysis, thermo gravometric analysis, drop weight tests, friction tests, card gap (shock initiation) tests, and materials compatibility tests. Information derived from the above tests serve as a basis to establish safe procedures and techniques to handle and process the chemicals into propellants. 

Shock sensitivity has been determined by a drop weight test ( BAM ) The lowest shock energy of the first reaction of 6 experiments was taken as security criterion. The experiments were realized with a 1 kg weight between 15 and 75 cm and a 5 kg weight between 15 and 50 cm drop height, respectively. 

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