Study On The Preparation And Charging Technology Of Smokeless Propellant For Fireworks Based On Low-grade NC

The preparation technology of smokeless fireworks propellant based on bamboo pulp nitrocotton and reclaimed nitrocotton which could be supplied continuously in this paper, in order to promote the development of sulfur-free and smokeless fireworks. Firstly, the feasibility of preparation for microporous spheric propellant(MSP) with bamboo pulp nitrocotton and reclaimed nitrocotton was analyzed and demonstrate. The MSP was applied to smokeless fireworks propellant. Then, on the basis of internal dissolution mothed of granulation technology, the influence of the average particle size and charge density of MSP was investigated by experiment, which indicated the average particle size and porosity increased with deviation to big size and bulk density decreased as ratios of solvent and ratios of emulsifying water increased. The velocity of mass burning was tested by straight tube method in different bulk density, demonstrated a faster transmitting speed of MSP with smaller bulk density. The MSP whose bulk density between0.2g/cm3and0.3g/cm3was charged modularly into smokeless propellants, and the smoke density and the emission height of warhead during launching were tested. The results indicate that, when the bamboo pulp nitrocotton-based and reclaimed nitrocotton-based modularize propellants of micro porous structure were applied on the1.2inch display shells, the initial velocity is higher than the traditional black powder charge of three times mass, slightly lower than the charge of retired single-based modularize propellants of micro porous structure of same mass, and the charge reached the required height for launching according to the "GB10631-2013" fireworks safety and quality upon calculation. In addition, there was only a small amount of smoke generated when set off, which is significantly less than the smoke generated by black powder, therefore, the bamboo pulp nitrocotton and reclaimed nitrocotton could be the basic energetic raw materials for sulfur-free and smokeless shells. Moreover, once the sulfur-free and smokeless shells were realized based on the bamboo pulp nitrocotton and reclaimed nitrocotton, there is no need to worry about the shortage of raw materials owe to their low price and abundant source.