Insert molding is a type of injection molding that bonds plastic and nonplastic materials. Typically, the nonplastic material is made from metal, but it can also be made of ceramic or another suitable material. The process involves placing the metal insert into the mold before injecting molten plastic. The insert and resulting molded part are then released from the mold to allow for cooling and finishing. The result is a finished metal-encapsulated plastic product with a high degree of durability and strength. This is a popular manufacturing technique for many different industries including medical, automotive, and electronics manufacturers as well as those who need to incorporate mechanical hardware such as threaded rods, pins, metal shanks or handles into their products.
Insert molding has several benefits over other methods of encapsulating metal components within plastics. The primary benefit is that insert molded parts are more reliable than those produced by other processes. This is because encapsulating the hardware in molded plastic eliminates secondary assembly and fastening operations. This helps to reduce vibration and shock resistance, as well as loosening, faulty terminations and misalignment.
The insertion process in injection molding also allows for the addition of more complex features and structures to plastic products. This is especially important for applications like metal-to-plastic connections or handles that need a robust, wear-resistant connection point. This is particularly useful for companies looking to cut down on assembly costs and improve the quality of their final product.
Manufacturers using insert molding also benefit from a reduced assembly time and cost when compared to overmolding or other processes. This is because insert molding produces a single shot while overmolding often requires two or more. It is also possible to use the same tool for both overmolding and insert molding which can speed up the manufacturing process further.
Injection molding is a very versatile process and can be used for various applications such as the production of plastics, thermosets, and polyurethanes. It is also a very affordable process that can be used to produce a variety of different shapes and sizes of products. It is also a very efficient process which can help to reduce overall costs for a company because it offers greater levels of flexibility than other manufacturing processes such as casting, machining and fabrication.
When designing an insert molded component, it is crucial to take into account the amount of pressure that will be placed on the plastic and metal parts when they are pressed together. This can cause damage or failure to the insert if the pressure is too high and must be taken into account when designing the mold.
When using an insert molding process, it is important to use a tool that can handle the amount of force that will be applied to the insert and plastic. This can be done by incorporating support features into the tool that can clamp the insert against as the liquid plastic is injected into it. For example, a good rule of thumb for insert dimensions is a 2:1 hand clearance-to-insert depth ratio.