Structure Optimization Design And Molding Process Control Of Medical Hemostatic Clip

Compared with the traditional metal hemostatic clip,the plastic hemostatic clip has obvious advantages,and is currently being used more and more.Aiming at the main problems of the plastic hemostatic clip in terms of structure,material,production technology,quality control,etc.,this article adopts structural optimization and strength analysis,molding process simulation and precise control of process parameters,etc.,to select the material and structure design of the hemostatic clip.,Research on product stress analysis and structure optimization,molding parameter optimization,production process monitoring and product quality inspection,etc.The specific contents are as follows:(1)The plastic hemostatic clip requires that the materials used are biologically inert,non-toxic and harmless,have high strength,and ensure that they will not fail during use.On the basis of comparative research,this paper determines three kinds of medical grade POM materials with better performance,through mechanical properties(tensile strength,bending strength,impact strength,hardness,etc.),rheological properties(melt index,torque rheological curve)Etc.)test analysis and comprehensive evaluation,select the material with the best performance as the material of the plastic hemostatic clip,to provide a reliable basis for product quality.(2)Although the plastic hemostatic clip product is small,it requires high structure and strength.It is necessary to ensure that it does not fall off,break,or damage the blood vessel during the clipping process,and it must also ensure that it can withstand the pressure of human blood after the clip is closed.Leakage and non-slippage.The above requirements are closely related to the design of the key structures of the hemostatic clip,such as the plastic hinge,the lock structure,the non-slip structure,and the keel structure.The shape and size of the hemostatic clip directly determine the performance of the product.This article focuses on the size calculation and innovative design of the abovementioned key structures,and obtains the initial design plan and detailed structure dimensions of the hemostatic clip with reasonable structure to ensure the realization of product functions.(3)In view of the product strength and the stress and strain problems in the use process,the product is subjected to force analysis,the mechanical model of the closing process of the hemostatic clip is established,the constraint relationship and boundary conditions are determined,and the finite element analysis software Abaqus is used to carry out the structural force Analyze and get the results of stress and strain at various parts of the product.According to the analysis result data,the maximum plastic strain value on the inner side of the plastic hinge is 76.99%,which exceeds the elongation at break of the POM material used,and there is a risk of fracture failure at this point.In response to this problem,the original structural plan of the plastic hinge was optimized and improved to reduce the maximum plastic strain value at the plastic hinge to 30.41%to ensure that the product can meet the requirements of use.(4)The injection molding process parameters of the product have a great influence on the quality and performance of the product,especially the deformation of the product,which directly affects the clamping and locking performance of the product.In this paper,the mold flow analysis software Moldex3 D is used to simulate the injection molding process.The goal is to control the maximum deformation of the product,and the four main parameters of melt temperature,injection rate,injection pressure,and holding pressure are used as variables to design orthogonal experiments.Plan and analyze the signal-to-noise ratio and variance of the experimental data,and then obtain the optimized molding process parameters.At the same time,in order to further verify the influence of the residual stress in the product molding process on its mechanical properties,the residual stress data obtained in the Moldex3 D software was imported into the Abaqus software through the interface file,and the structural force coupling analysis was carried out.The results showed that the analysis was similar to the original structure.Compared with the result value,the maximum stress value of the product obtained by the coupling analysis increased by 9.53%,and the maximum plastic strain value increased by 18.71%,reaching 36.1%,but it remained within the maximum allowable value range of the product,which can meet the requirements of the product.(5)In the injection molding production,the fluctuation of the molding process parameters will have a great impact on the quality of the product,especially the fluctuation of the cavity pressure,which directly affects the performance of the product.For this reason,this article installs sensors on the mold,introduces a cavity pressure monitoring system,designs orthogonal experiments to explore the relationship between cavity pressure,process parameters and product molding quality,verifies the parameters obtained by mold flow analysis and optimizes and obtains the standard mold Cavity pressure curve,and then use the production control system to monitor and control the injection molding production process in real time,to minimize the impact of process parameter fluctuations on product quality.(6)Product quality control is an important link in the production process and an effective measure to ensure product quality.For plastic hemostatic clip products,which method is used to detect which indicators are the difficulties in product quality control.This article carried out research on product quality control technology for plastic hemostatic clips,and innovatively proposed scientific indicators and methods for product quality testing,including opening force testing,pressure resistance testing,tensile force testing,etc.,and established criteria and inspection procedures to ensure product quality Strictly controlled.According to the main problems existing in the plastic hemostatic clip,the research has been conducted in the aspects of structural optimization design,production process control,product quality inspection,etc.,and certain results have been obtained,which has good innovation and practical application value.