During the plastic injection mold trial process, defects like short-filling, trapped air burns, high internal stress, flow marks and weld lines often occur. For those problems, the first solution would be adjustment of the plastic injection molding process, and another consideration would be the reasonable design of the mold gate. Once both of these problems … Read more
Steel Selection for Molding Components Molding components refer to the mold parts or components which have a direct contact with the plastic materials to form a product, such as mold cavities, mold cores, sliders, inserts and lifters, etc. The steel quality of the molding components has a direct influence on mold quality and service life, … Read more
Type of parting line(surface) 1.Horizontal parting line 2.Oblique parting line 3.Curve parting line 4.Parting line on shut off holes 5.Parting line on side holes General Principles for Selection of Main Parting surfaces Protect the Inserts Usually, product disassembly needs to be considered before selecting the main parting surface, i.e. identify the secondary parting surfaces, … Read more
As an elastic component, the spring plays a very important role in a plastic injection mold, because a properly located spring is able to provide the necessary driving force that the mold needs. For example, when the ejection mechanism completes the ejection action of a plastic part, a spring can be applied to force the … Read more
The Runner Concept The runner refers to the melt flow passageway between the end of the main runner and the gate, which is used to change melt flow direction and allocate it to each cavity in a stable and balanced way. The basic design principle of the branch runner is little pressure/heat loss, with the … Read more
The main runner refers to the melt flow passageway from the joint between the injection molding machine nozzle and the mold sprue bushing to the starting point of the branch runner. –The design has to minimize melt temperature drop/pressure loss. –Adopt the cone shape design, to facilitate removal of the condensed material Forms of The … Read more
In a mold structure, the cooling channel tends to leak at the joints between mold plates as well as those between the mold plate and the core insert due to the existence of joint gaps. To prevent this from happening, O-rings are often applied to seal the joints. Mold structure design should take the following … Read more
1. The lifter is mainly used to form the internal undercuts of a molded plastic part, and at the same time it also offers ejection function. The mechanism features a simple structure but poor rigidity and a short travel distance. The typical structure is shown as below: Most injection mold company usually apply the lifter … Read more
There are many types of guide pin structures in plastic injection mold application, among which the standard structural design is shown in the figure below. A guide pin has to serve as the cylindrical surface of concentric circles of different diameters. Based on structural dimensions and material requirements, a round steel bar with an appropriate … Read more