Design Of A Bag Box Filling Metering Device For Powdered Hazardous Chemical Packaging Systems

Nowadays,most of Chinese hazardous chemical manufacturers still use packaging equipment with a very low degree of automation.The main reason for this was that hazardous chemicals have a flammable,explosive and corrosive chemical nature,and the existing advanced packaging machinery cannot safely and effectively achieve the packaging of hazardous chemicals.How to achieve "unmanned factory" or "black light factor”,the development of a set of suitable for hazardous chemicals packaging requirements of fully automatic packaging equipment was the need of the market,but also the needs of national conditions.The subject of this research was the feeding and metering device in the packaging system for powdered hazardous chemicals:Firstly,the physical and chemical properties of hazardous chemicals,relevant transported metering safety regulations and design requirements were integrated,the research ideas of this topic were formulated,and a suitable way of supplying and measuring hazardous chemicals was selected.The final decision was made that the feeding method for powdered hazardous chemicals was the fast and slow screw feeding method and the metering method was the under weighing gross weight type.According to the chosen solution,the structural composition of the filling and metering device was analysed;combined with the design of the parameters of the screw conveyor and the theory of powder underfeeding and powder screw conveying,a screw feeding shaft with a combined pitch was selected;the movement and force of the particles inside the feeding shaft was analysed as a starting point,and the key parameters of the feeding shaft and the silo were calculated in detail.Other components and structures inside the device were designed for safety;in the metering device,the components in the under-weighing gross metering device were designed in detail according to the unique physicochemical characteristics of hazardous chemicals,and the components of the filling metering device were designed using the 3D modelling software SOLIDWORKS.Secondly,the three-dimensional model of the feeding device was simulated and analysed using the EDEM advanced discrete unit method to visualise the movement of the powdered material inside the feeding device,making it possible to visualise the movement and transport trajectory of the particles throughout the feeding process.The analysis shows that the conveying speed of the powder could reach the design requirements at the theoretical speed.The powder velocities of the four different functional sections of the feed shaft of the pitch combination are also analysed to verify that the pitch combination screw feed shaft could make the whole conveying process smooth.This provides a continuous and uniform supply for subsequent dosing.With all the analysis taken into account,the relevant device was produced,assembled and commissioned,and compared with the simulation data,and after comparison,it was concluded that the filling and metering device of the hazardous chemical packaging system designed in this topic meets the requirements of the indicators,and had a high reliability and safety.