The shape elements of medical injection molded parts determine the processing accuracy of the mold, the number of mold cavities, and the main factors of mold life. When opening the mold, the engineers will design a reasonable number of mold holes according to the appearance structure and shape of the product to meet the processing accuracy of medical injection molded parts, improve production efficiency and reduce production costs, and complete customer delivery on time and quantity.
Combining the product function requirements, as well as the 2D drawing tolerance requirements, external requirements, molding machine requirements, and molding material characteristics, the designing needs to take into account the function and size, the mold needs to shrink, and the compensation calculation needs to be done in the area with large deformation or the area with large shrinkage, and the steel space can be reserved in the early stage.
The structure of medical injection molded parts: In simple terms, the demoulding structure is inconsistent with the opening direction of the injection molded parts. Lateral core-pulling movement is required to achieve the normal demolding state of the medical plastic injection molding parts.
To ensure the reliability of the parting surface of the mechanism, try to avoid the phenomenon of thin iron and sharp iron, because during the movement, with the long-term movement and the increase of temperature, it is easy to deform or break.
When moving the structure after the china mold design is completed, it is necessary to perform a 3D motion simulation and check whether there are hidden safety hazards and interference.
First understand the assembly requirements of holes and threads, 2D dimensional tolerance requirements, and torque requirements. Regardless of the fixed mold part or the movable mold part, in general, the mold is processed with inserts to ensure processing accuracy and convenient maintenance.
Especially for thin-walled, narrow-thin and long-shaped, precision injection molding parts, and products with large tightening force, it is necessary to consider the changes in the product that are prone to indentation, protrusion, warpage, bending, and distortion during molding. Therefore, make a change plan in advance, including the optimization of the pouring system, the optimization of the temperature control system, the mold correction method, the improvement of the material characteristics, etc., and take effective measures in advance to control the risk in the cradle.
Especially when the product structure has a sliding block and an inclined top, the motion interference analysis should be carried out in conjunction with the ejection mechanism. Sometimes in the case of a three-plate mold with a thin nozzle, the interference during the pickup should be analyzed in conjunction with the elements of the injection molded part. If it is in the case of manipulator picking up, whether the guide post and pull rod interfere with the nozzle of the dispensing spout, etc.!
Under normal circumstances, the product is prone to flow marks, sink marks, insufficient filling, silver streaks, obvious bonding lines, air trapping and other undesirable phenomena on the outside of the product during the T0 mold trial process.
The above problems with T0 can basically be found in the process of mold flow analysis in the early stage. If there is time in the early stage, if you do a mold analysis, the above problems can be improved in advance.
The best result of plastic injection molding medical parts is the batch, which needs to consider the three elements of molding: temperature, pressure, and time!
The impact of plastic materials on mold steel in the batch process, such as: POM, PA66 and other materials, mold steel is made of steel with good corrosion resistance.
When the structure is in motion, the wear resistance of the steel is analyzed. Try to use two different properties of the steel during the movement, so as to avoid the chemical reaction during the movement and the same kind of steel is easy to wear.