1. The characteristics of precision injection molding are that the dimensions of injection molded parts require high precision and small tolerances.
The conditions that must be met to achieve precision injection molding are:
(1) The material of the mold is good, the rigidity is sufficient, the dimensional accuracy of the cavity, the smoothness and the positioning accuracy between the templates are high.
(2) A precision injection molding machine is required.
(3) A precise injection molding process is required.
(4) Materials suitable for precision injection molding processes should be selected.
Most commonly used precision injection molding materials include the following: POM, POM+CF (carbon fiber), POM+GF (glass fiber), PA, FRPA66 (enhanced PA), PC, and the like.
An important method to ensure the dimensional accuracy of injection molded parts in the precision injection molding process is to control the shrinkage of the injection molded parts, including the heat shrinkage, phase shrinkage, orientation shrinkage, compression shrinkage and elastic recovery of the injection molded parts.
2. The characteristics of ordinary injection molding are that the dimensional accuracy of injection molded parts is not high. Generally, it can be assembled as a standard. The appearance requirements of injection molded parts are relatively high. If necessary, secondary processing (such as injection) may be used. Improve appearance defects.
Ordinary injection molding does not require a particularly sophisticated injection molding machine, nor does it require specially specified materials. Generally used thermoplastics can be used for production. Therefore, the common injection molding process is also widely used in the modern plastic industry.