Insert molding (insert molding) refers to a molding method in which a pre-prepared insert of different materials is placed in a mold and then resin is injected, and the molten material is bonded to the insert and solidified to form an integrated product.
Injection molding on the substrate (outsert molding) refers to the method of embedding injection molded parts on a part of the metal plate surface.
The two molding methods are essentially the same. Its characteristics are as follows:
The combination of the easy formability and bendability of resin and the rigidity, strength, and heat resistance of metal can make complex and exquisite metal-plastic integrated products.
Especially by using the combination of the insulation of resin and the electrical properties of metal, the molded products can meet the basic functions of electrical products.
The pre-forming combination of multiple inserts makes the post-engineering of the product unit combination more rational.
Insert products are not limited to metal, but also include cloth, paper, wire, plastic, glass, wood, coils, electrical parts, etc.
For rigid molded products and curved elastic molded products on rubber sealing pads, after injection molding on the substrate to form an integrated product, the complicated work of arranging the sealing ring can be omitted, making the automatic combination of the subsequent process easier.
Because it is the joint between the molten material and the metal insert, compared with the press-in molding method, the gap between the metal insert can be designed to be narrower, and the reliability of the composite product molding is higher.
Select the appropriate resin and molding conditions, that is, for products that are easily deformed and damaged (such as glass, coils, electrical parts, etc.), the resin can also be sealed and fixed.
Select the appropriate mold structure, the insert can also be completely sealed in the resin.
After the insert is formed, it can also be made into a product with a hollow groove after the core hole is removed.
The combination of a vertical injection molding machine, manipulator, and insert product alignment device can realize automatic production in most insert molding projects.
Considerations for the Design and Selection of Automatic Insert Molding System
Metal insert molding is prone to uneven molding shrinkage, and the limit test of the shape and dimensional accuracy of important parts should be done in advance.
The metal insert is easily deformed and displaced during the injection process, and the mold composition and the design of the mold shape that is easy to maintain the metal insert should be fully considered. For products in which the shape of the insert cannot be changed, prior testing is indispensable.
When the arrangement of the metal inserts is separated and the conveyor is used, the contact between the metal inserts and the contact between the inserts and the vibrating ball will cause slight damage to the surface of the inserts, which will affect the product quality. The allowable limit range of its quality should be confirmed in advance.
The jaggedness, warpage, material thickness difference, diameter difference, and thickness difference caused by gold plating processing of metal inserts caused by stamping processing should be measured in advance. On this basis, the matching selection design of the automation device and the design of the mold structure are carried out.
Predictable matters that restrict the structure of the mold, such as the position of the mold gate, the molding cycle, etc., should be resolved in advance as much as possible or have corresponding improvement measures.
It should be confirmed whether the metal insert needs to be preheated or dried. The purpose is to ensure product quality and molding stability.
The various detection devices installed in the mold are used to ensure the stability of the molding action under the influence of environmental conditions such as heat, force, and vibration on the mold. It should be confirmed whether they are used.
In order to avoid metal inserts and fine pieces of molded products from accumulating in the mold cavity, an air-blowing device can be assembled if necessary.
Due to the high investment price of system equipment, it is necessary to fully consider whether the production capacity of the equipment can be guaranteed before adopting it. When using a special machine, it is necessary to ensure that the product can be continuously produced without form updates for several years.
When using a general-purpose machine, it is necessary to confirm how many combinations of inserts with multiple varieties and small batches are produced. If mass production cannot be guaranteed as a whole, it is difficult to recover the fixed assets of each product. In this case, it is necessary to replace a part of the device to adapt to the variety of update requirements within a certain range.
The accuracy of the metal insert, the shape of the insert, and whether the mold is conducive to insert molding and the shape of the molded product are factors and technical decisions that determine the insert molding rate, productivity, and molding cost conditions.
The effective combination of injection machine, mold, and automation device and how to function in a short time are the key to determining the automatic insert molding system. Welcome to contact our company, our engineers will give you professional advice as soon as possible.