Study On The Online Continuous Measurement Of Powder Composition And The Mixing Uniformity Between The Components

In order to online measure gunpowder composition content and the mixing uniformity continuously and accurately,and improve the quality and performance of gunpowder,online measurement systems of nitrocellulose(NC),nitroglycerine(NG)and cyclotrimethylene trinitramine(RDX)were designed firstly and its accuracy was verified.Secondly,powder flow tester were used to test the liquidity of superfine ammonium perchlorate(AP),cyclotrimethylene trinitramine(RDX),nitroguanidine(NQ),and compared the liquidity of these three kinds of gunpowder solid components.Finally,two kinds of solid components with different liquidity were mixed and the whole process of mixing was detected by near infrared spectrometer,and the relationship between the powder liquidity and mixing uniformity was also investigated.Specific content was presented as follows;Firstly,online measurement systems of nitrocellulose(NC),nitroglycerine(NG)and cyclotrimethylene trinitramine(RDX)were designed respectively,and straight tube mass flowmeter was used to measure the content of gunpowder components online.Through the online continuous measurement test,the accuracy and stability of the measurement system were verified.The results show that online continuous measurement system of these three kinds of gunpowder components can be proved to be accurate and stable,and measurement errors are within 1%,which can meet the requirements of gunpowder automation and continuous production.Secondly,the powder flow tester was employed to test the liquidity of AP,RDX,NQ.The results show that after ultra-fining,the sequence of liquidity is AP,RDX,NQ,which could be attributed to the difference of their size distribution and morphology features.Thirdly,different solid components of gunpowder were mixed pairwise,and the whole mixing process was detected by near infrared spectrometer.In addition,Moving Block of Standard Deviation(MBSD)method was used to quantitatively present the difference between the spectra at different time and reflected the change of mixing uniformity during the mixing process of different solid gunpowder components in real time and judge the mixing endpoint.The results show that the mixing of AP and RDX,AP and NQ,RDX and NQ reached the mixing endpoint at 180 s,213 s,250 s,respectively.This indicated that better liquidity of solid components leads to shorter time in reaching the mixing endpoint.