Negosentro | Precision Injection Molding: Explained | Precision injection molding or PIM is the advanced technology used by manufacturing industries to produce highly functional parts. It is a form of plastic injection molding method that needs precision machines and molds. The technique is used to create specialized parts such as optics, medical devices, automotive, electronics, etc. The parts manufactured from this specialized technique then can be used in the manufacturing of the latest technical devices.
Factors Responsible For Precision Injection Molding
- Products for precision injection molding should be 0.01 – 0.001 mm.
- Injection molding machines should be of high pressure and high speed.
- Clamping system should be of high precision locking and enough rigidity.
- Locking precision should contain high repeatability, and should be stable, adjustable and have uniform clamping force.
- The high position precision mold should contain the adequate measurement, temperature, flow and pressure so as to control the corresponding precision accurately.
Materials Used In Precision Injection Molding
There is a specific requirement of materials for precision injection molding:
- PC and GFPC: Good molding, flammability, weatherability, stability, high rigidity, and good wear resistance.
- PBT reinforced polyester having less molding time. The forming time is as follows:
PBT = POM = PA66 = PA6.
- POM and glass enhancement (GF) or carbon fiber reinforced (CF). These materials are difficult to burn, and have good dielectric properties, weatherability, fatigue resistance, and creep resistance.
- PA and glass fiber reinforced PA66. These materials have good flow performance, and should be wear resistance and strong impact resistance. They can be used to form products having wall thickness of 0.4 mm.
- Plastic resin helps to control the quality of the final product. A best suitable example is Acrylonitrile (ABS). ABC is a thermoplastic polymer and it can maintain its elasticity in high temperatures too.
- The molding materials should be of low shrinkage capacity, as the materials of higher shrinkage capacity may ruin the entire product.
Precision Injection Molding Machine- Characteristics And Features
The machines should be capable of managing the accuracy of the product as well as its repeatability and the injection pressure in the machines should be around 392 MPa.
There are certain features that should be kept in mind while selecting precision molding machines:
- The plasticizing parts consist of a check ring, material barrel, screw, and screw head. These parts should be designed into a structural form with high injection efficiency, good homogenization degree, and strong plasticizing ability.
- Parts should be dimensional tolerant.
- Stiffness of the clamping system. It is required due to the high injection pressure of the pressure injection machine.
- Fast open and closed die speed, which is approximately 60mm/s.
Conclusion:
Precision injection molding is effective and uses the latest technologies to produce effective manufacturing parts. It is a better and faster approach as compared to the traditional molding method. It helps to develop much stronger and more cost-effective products with the latest trends. Therefore, all the manufacturing industries are stepping towards this technology.
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