Insert molding is an industrial process, which makes use of modern injection molding technology. This molding process has revamped the present day manufacturing. Insert molding process blends plastics and metal, or several combinations of components and materials into a single unit. This molding process uses engineering plastics for enhanced tensile strength and weight reduction, and wear resistance. It also makes use of metallic materials for conductivity and strength.
The metal inserts and bushings strengthen the mechanical properties of plastic or thermoplastic elastomer products. This post will discuss everything about the insert molding process.
Advantages of Insert Molding:
Insert molding has the following advantages, which makes it an optimal process for several applications:
- Increases Design Flexibility: The insert molding allows virtually unlimited configurations, which works in favor of designers. For example, while manufacturing a 3D circuit board, over molding allows the circuit board to move freely through the part, from inside to outside, down in the holes, and up walls, and the plastic ties it all together.
- Reduces Assembly and Labor Costs: As insert molding combines a number of components with thermoplastic, it helps minimize the assembly and labor costs. For example, you can over mold a single stamping, and then perforate it to create numerous circuit paths.
- Increases Reliability: As every part is firmly held in thermoplastic, an insert molded component averts loosening of parts, improper terminations, misalignment, and other problems, thus increasing the reliability of the component. The thermoplastic resin also offers enhanced resistance to vibration and shock.
- Reduces Size and Weight: As it eliminates the need of connectors and fasteners, and combines the physical strength of metal inserts and resin, insert molding delivers components that are smaller in size and lighter in weight.
Steps of Insert Molding:
Insert molding for plastic is carried out in following steps:
- Step 1: As a first step, a customized mold is loaded with inserts. Inserts can either be loaded manually or robotically.
- Step 2: Molten plastic is then added into the mold.
- Step 3: After cooling, the mold is opened and the components are removed.
- Step 4: Components are separated from sprues and examined.
- Step 5: Post-molding assembly can consist of a range of secondary operations, like:
- Circuit testing
- Die cutting of stampings into discrete circuits
- Micro-soldering
- Bonding
What are the Important Considerations for the Process?
It is necessary for the inserts to survive the injection molding process, as some temperatures and pressures can damage them. Design solutions protect the inserts, along with providing the benefits of insert molding. This helps in completing the design. The entire process of insert molding needs a lot of experience.
This process is developed further with a few simple considerations:
- Utilization of a firm offering insert molds that defines which specific technology and components are joined into a single component
- Undercut features that provide additional holding strength within the molded part
- Provision of means for holding the insert throughout the molding process
What All Industries Does the Insert Molding Process Serve?
Nowadays, insert molding has become popular among various industries. Some of the industries where insert molding process is widely used are as follows:
- Electronic
- Medical
- Aerospace
- Pharmaceutical
- Safety
- Defense
What are the Applications of Insert Molding?
Present custom insert molding applications are wide ranging, which include:
- Military equipment
- In-mold labeling (IML) and in-mold decorating (IMD), in which a printed film is injected into the mold cavity. A plastic resin is injected against the film, which results in a decorated part that is cost effective and durable.
- Medical instruments and devices, such as tube valves and needle hubs
- Encapsulated bushings, studs, and tubes
- Knobs for appliances, assemblies, and controls
- Threaded fasteners
- Encapsulated electrical components and electronic devices
This is how and why insert molding is done for plastics. There are a number of firms providing insert molding services. Make sure you contact the right one for your molding requirements.
