| Dry granulator is one of the key equipment for the preparation of traditional Chinese medicine tablets and granules.Drug powder is compressed into tablets in a dry granulator.The quality of the tablets determines the yield of the final drug granules.Therefore,the study of dry granulation technology to improve the tablet quality and drug granule yield is of great significance.At present,the dry granulators independently developed in China generally have problems such as low control accuracy and low tableting quality.Research on pharmaceutical powder roll forming technology is also very lacking,so it is even more necessary to carry out related research on dry granulation technology Research work to break the monopoly of foreign technology and products and promote the localization of dry granulators.In this paper,through the experimental research of dry granulation technology and numerical study of the rolling process of pharmaceutical powder,we grasp the relationship between the quality of pharmaceutical powder tableting and the operating parameters,geometric parameters and friction coefficient of dry granulator.The specific research contents include:(1)Firstly,the application of dry granulator in the pharmaceutical field and the research status of dry granulation technology are introduced.This article describes the research results of theoretical methods,numerical methods and experimental methods for the research on the roll forming of pharmaceutical powders,and points out Advantages and disadvantages of the three methods.(2)The effects of the roll speed and the feed screw speed on the tablet density and thickness of the drug powder and the effect of the ratio of the roll speed to the feed screw speed on the drug particle yield were studied by experimental methods.When the speed of the feed screw is fixed,as the speed of the roll wheel increases,the density of the discharged sheet continuously decreases and the thickness decreases.The quality of the sheet is increased first and then decreased.As the speed increases,the density of the discharged sheet increases continuously,and the thickness increases.The quality of the sheet first increases and then decreases;as the ratio of the speed of the roll wheel to the speed of the feed screw increases,the yield of material particles increases first.Decreased,highest at 1: 4.In addition,the density distribution of the discharged sheet under different operating parameters was studied,and it was found that the density of the discharged sheet had a rule of large in the middle and small in the width.(3)Firstly,the related knowledge of numerical methods for researching the roll forming of pharmaceutical powders is introduced,and the basic steps of the numerical method’s solution steps and numerical models are explained.Then,the powders with different ratios of the rotation speed of the roller and the feed screw are studied by numerical methods.The calculation results show that as the ratio of the rotation speed of the roller to the speed of the feeding screw increases,the density of the discharged sheet continuously decreases and the length increases.In line with the test results.(4)The influence of the geometric parameters and friction coefficient of the dry granulator on the quality of powder tableting was studied by numerical methods.The research results show that too high gap between the rollers will cause the density of the discharged sheet to be too low to be compressed into tablets.Too low a gap between the rollers will cause the density of the discharged sheet to be unevenly distributed.The effect of density is related to the rotation speed of the roll wheel.Too low width of the roll wheel will cause uneven density distribution of the discharge sheet.Too low height of the feed channel will lead to lower density of the discharge sheet.The proper inclination angle of the feed channel can increase The density of the discharge sheet and the discharge channel have little effect on the quality of the powder tablet;the surface friction of the roller wheel is conducive to the rolling of the drug powder,and the friction of the side seal and the feed channel friction on the powder of the drug powder Compression molding has a negative effect. |
