What should be paid attention to in the processing of injection molds? During the molding process of plastic injection molding thermoplastics, the volume changes due to crystallization, strong internal stress, large residual stress remaining in the plastic part, and strong molecular orientation. Therefore, compared with thermosetting plastics, the shortening rate is larger, the shortening rate range is wide, and the directionality is obvious. Additionally, shrinkage after forming, annealing, or conditioning is typically greater than that of thermosets.
Plastic mold manufacturing
When injection molding a plastic part, the outer layer of molten material and the surface of the cavity cool immediately, forming a solid shell of low density. Due to the poor thermal conductivity of plastic, the inner layer of the plastic part is slowly cooled to form a high-density solid layer, and the shortening rate is large. As a result, the wall thickness, slow cooling and high density layer thickness are further reduced.
In addition, the presence or absence of perforated parts and the arrangement and number of perforated parts directly affect the direction of movement, density dispersion and crack resistance, etc., so the characteristics of plastic parts have a greater impact on size and size. Shortened directionality.
Factors such as the shape, size, and dispersion of the feed port directly affect the direction of data movement, density dispersion, pressure retention and shortening, and molding time.
In injection molding, the direct feed port and the larger feed port section (especially the thicker section) have a smaller shortening rate but greater directionality, while the shorter feed port width and length are directional smaller. The side near the inlet or parallel to the material flow direction is greatly shortened. Injection molding processing order
Copyright © 2022 BOTTLE - aivideo8.com All Rights Reserved.