Injection Moulding is a popular manufacturing process. It involves injecting material into a closed mold to make identical parts in large quantities. A design will be created utilizing a range of materials to help with the molding process.
To get a better understanding of the process, grains of plastic material are conveyed into the machine. The molten plastic material is then fed into the cavity under pressure via runner systems. Using specialized equipment and techniques, you will be able to determine the mold’s shape. You’d have a finished item once it had cooled and been removed from the mold. This process is then repeated, resulting in an identical part for each cycle.
The process seems pretty easy and simple, but according to some expert injection molding manufacturer and suppliers, plastic molding comes with its bright and dull aspects. Let’s have a look at some important benefits and drawbacks of this process.
Plastic Molding Machine Advantages
1. Precision plastic injection molding part
Plastic injection molding is ideal for pieces with a lot of detail. Molding, in comparison to other processes, allows you to include more elements with very small tolerances. Start by looking at the illustrations. The basic molding contains bosses, side cores, ribs, metal inserts, and holes that may be held in the palm of your hand.
2. High repeatability
After your mold tool is created, you can make identical things over and over again. Whether it is a simple ground switch or a major machine part. A well-made mold tool will last a long time provided it is properly cared for by the molding machinery makers.
3. Low cost per part
While the plastic injection molding tool has a hefty initial investment, the cost per part is extremely inexpensive after that. Other plastic processing procedures, such as polishing, may take multiple operations. Whereas injection molding can handle everything at once. It would cost hundreds of dollars per part to CNC machine. Injection molding is the way to go if you want to go into full production.
4. Fast
Cycle times as short as 10 seconds are possible. When you pair that with a multi-impression injection molding tool, you can swiftly produce a large number of products. Because it’s a specialty material with a lot of characteristics to mold correctly, the portion above takes a little longer. But at roughly 50 seconds each cavity per hour, you’d still produce 70 parts per hour. A one-off CNC machining will take half a day, and 3D printing would take much longer!
5. Material choice
For plastic injection molding, there are a plethora of materials to choose from. Antistatic plastic, chemical-resistant plastics, infrared, bio compostable, thermoplastic rubber, and with color compounding or masterbatch coloring, the possibilities are unlimited.
This advantage works wonders for a long list of industry manufacturers and major product suppliers such as ball valve suppliers in South africa.
6. Special Surface Finishes, Engraving & Printing
The injection molding tool can be produced with a particular finish that will show on the molding in addition to a variety of colors. You can choose from a variety of finishes, such as leather-look, high shine, soft-touch, sparks, and so on. Logos or other text can also be etched on the tool.
Finally, you may have your moldings printed because a variety of inks that work well on plastic are available.
7. Little plastic waste
Injection molding has a high level of part reproducibility. Sprues and runners (leftover bits of plastic that are commonly generated by the ‘tunnels’ through which the plastic material reaches the actual mold) can be reground and reused as well. You may find out more about injection molding’s environmental impact on our various online websites.
Plastic Molding Disadvantages
Don’t the advantages sound fantastic? Of course, but there are some drawbacks as well:
1. High Initial Cost
Before the go-ahead or manufacturing is given, numerous rounds of drawing and prototyping are often required. The injection molding tool that will be used to make the molds will then need to be designed and manufactured.
The mold tool is a complex piece of equipment that requires a lot of people, material, and machining time to create. Also, it is the most expensive part of the injection molding process. Of course, once everything is in place, the part cost is quite low, and the repeatability for hundreds or even thousands of moldings is very high.
2. Initial lead time
It can take several months of design, development, and tool production to bring a product from concept to completion. However, if you know exactly whatever you want, you can still have the final moldings in as little as six weeks. And, as indicated under benefits, once the tool is in place, running the moldings takes very little time. Especially if you have a multi-impression mold tool.
3. Large Part Size Limitations
In order to create plastic injection moldings, massive machines are required. Large pieces necessitate a massive mold tool and are therefore highly expensive to produce. In this situation, depending on the sort of product required, a technique like Plastic Fabrication could be a better option as compared to injection molding.
4. Careful design needed
To minimize tooling concerns like undercuts (which will drive up tooling costs dramatically), locked-in features, and insufficient draft, plastic moldings must be carefully designed. The content and temperature must be considered when designing the wall. Otherwise, the mold may not fill completely. To guarantee that the product is aesthetically acceptable, the positioning of ejectors, as well as the cooling lines, will also need to be addressed.