Overview of Post-Injection Processing
Injection molding is a manufacturing process for producing parts from thermoplastic and thermosetting material by injecting it into a mold. Post-injection processing is an important process for getting parts with the correct properties and dimensional completeness. After injection molding, parts usually require additional processing methods such as deburring, surface treatment, cutting, drilling, assembly and more.
Deburring
Deburring is the process of removing sharp edges. These sharp edges cause friction and reduce service life, so they need to be removed. In injection molding, the part is ejected from the cavity with the uncut gate. Therefore, the gate has to be cut and the parting line has to be removed. This can be done manually with a file, abrasive paper or chisel, or with a separate deburring machine. Other forms of deburring include milling and buffing.
Surface Treatment
Surface treatment is a very important part of post-injection processing. This is because the surface usually has some defects such as flow lines, particles, scratches, etc. There are several surface treatment methods, such as sanding and buffing. Sanding is used to smooth the surface, while buffing is used to give a high gloss finish. Other treatments include polishing, oxide coating and painting.
Cutting
Cutting is used to separate the parts or to machine them into their final shape. Cutting is usually done by shearing or milling. Shearing is a process in which the part is cut with a cutting die. Milling is used to machine the part into its desired shape. It involves using a cutting tool to remove the material from the surface in a controlled manner.
Drilling
Drilling is a process used to create round holes in the part. It is usually done with a drill press. Drilling can also be done with a CNC machine for greater accuracy. In drilling, a drill bit is used to cut out material and to create the hole. The size of the hole depends on the size of the drill bit.
Assembly
Assembly is usually the final step of post-injection processing. In assembly, various parts are joined together to form a single part. This can be done by screws, rivets, adhesives, welding or other methods. Assembly is a very important step in ensuring that the part is fit for purpose and meets all customer requirements.
Conclusion
Injection molding is a very popular manufacturing process that is used to produce parts. Post-injection processing is a vital part of this process, as these parts require additional work to make them fit for purpose. This includes deburring, surface treatment, cutting, drilling and assembly. By following the correct post-injection processing steps, it is possible to produce a high-quality product that meets all customer requirements.
