Injection mold is a very important process and it has become the prerequisite for the development and production of diversified industrial products. It has many applications, including but not limited to: electronic parts, medical devices, automotive parts, food packaging and toys.
In order to manufacture a product using the injection molding process, you first need an injection mold. An injection mold is a tool that is used to create the desired prouct shape. The cost of an injection mold can vary depending on the size and complexity of the design.
In this article, we’ll explain in details about types of injection molds, different factors which affect its pricing and how to reduce injection molding cost.
Learn about Different Types of Injection Molding
Here is a brief introduction about those most popular mold types available here.
Cold runner Mold: A cold runner mold is a type of injection mold that uses a simple, non-heated channel to transfer the molten plastic from the injector nozzle into the cavities of the mold. This type of injection molding is typically used for simple, low-cost parts or when a smaller part quantity is needed.
Hot runner Mold: A hot runner mold is a type of injection mold that uses heated channels to transfer the molten plastic from the injector nozzle into the cavities of the mold. This type of injection molding is often used for multi-cavity molds and complex parts. With this type of system, hot plastic is injected directly into the cavities through nozzles, with the excess melting and flowing back out to be recycled.
Two-Shot Mold: A two-shot mold is a type of injection mold that injects two different types of plastic into the same mold cavities at the same time. This process is used when a part requires two different color or material plastic parts in order to be completed, such as automotive handles or medical device components.
Family Mold: A family mold is a type of injection mold that has multiple cavities for producing parts with different shapes and sizes. This type of injection molding is used when multiple parts need to be produced at the same time in order to save time and cost.
Single-cavity Mold: A single-cavity mold is a type of injection mold that has only one cavity for producing parts with the same shape and size. This type of injection molding is used when producing large quantities of identical parts.
Insert Mold: An insert mold is a type of injection mold that uses inserts to create complex parts. This type of injection molding is used when the part requires intricate details such as threads or other features that cannot be easily molded with traditional injection molds.
Overmold: An overmold is a type of injection molding process where one material is molded over another in order to create a part with multiple layers. This type of injection molding is used when the part requires parts with different colors or materials, such as rubber grips on plastic handles.
Different Factors that Influence the Cost of Injection Molding
Injection molding is one of the most commonly used manufacturing processes for producing plastic parts. The cost of molding a small, simple part in one material might be as little as a few hundred dollars. On the other hand, the cost of molding a large, complex multi-material part can be significantly higher – potentially reaching into the tens of thousands of dollars. To accurately calculate the cost of an injection mold, several factors need to be taken into account, including the size and complexity of the part being produced, the type of plastic being used, as well as the number of molds required and their complexity.
To calculate the cost of injection molding, you need to know the following information:
-The size and shape of the product
-Type of plastic used
-The number and complexity of molds required
-Injection mold design
-Steel type for core/cavity machining
-The number of cavities in the mold
-Runner type
-Plastic part surface finish
The Size & Complexity of Parts: Generally speaking, larger parts tend to be more expensive than smaller parts due to the fact that they require larger molds which are more costly to produce. Additionally, complex geometries or multiple cavities may also increase tooling costs, it often involves 2 main processes for molds making like CNC machining and EDM machining.
Type of Plastic Used: Different types of plastics have varying levels of strength, flexibility and rigidity which can affect not only the cost of the part, but also the overall production process. For example, some plastics are more suitable for high-temperature injection molding than others and therefore require specialized molds and additional tooling which can increase costs.
Type of Core/Cavity metal: The core and cavity of the mold are typically constructed from steel, aluminum or other metals. Different types of metals have varying levels of strength, durability and wear resistance which can affect both tooling costs as well as the overall longevity of the injection mold. We can suggest the right type of steel depending on your mold life expected. In our workshop, the popular steel types used include P20/NAK80/S136.
Number & Complexity of Molds: The number and complexity of molds required to produce a part will affect its overall cost. Simple parts may only require one single-cavity mold while more complex parts may need multiple molds with different cavities to create each individual component. Multi-cavity molds, which can produce multiple parts in one shot, are more expensive than single-cavity molds.
Injection Mold Design: The design of an injection mold is crucial in determining the accuracy, quality, repeatability and performance of a plastic part. An experienced designer should be consulted when designing an injection mold as their expertise and knowledge can help keep costs down. At Shanghai Elue, we always provide DFM reports and Mold flow analysis to confirm with customers before mold designs start.
Injection Molding Machine: The size of the injection molding machine is another important factor that can influence the cost of a project. Generally speaking, larger machines cost more than smaller ones and therefore should be used only when necessary to ensure optimal cost efficiency. at Shanghai Elue, we have a variety of injection machines from 90T-850T.
Labor cost: There are 3 types of labor costs involved with injection molding, like molds setting up, molds testing, injection production operating or guarding even if some machines may be automatic. Shanghai Elue has a team of technicals and skilled workers to control the cost for labor.
Secondary Processing: After the injection molding process, some parts may require additional processing such as assembly, painting or plating. The cost of this secondary processing will vary depending on the complexity of the part and the type of processing required.
Production Volume: Finally, the quantity of parts being produced is another factor that affects injection mold costs. Higher quantities will typically benefit from larger cavities and greater efficiency, resulting in lower per-unit prices for each part. However, for low-volume runs with more intricate designs, individualized tooling and manual assembly may be necessary, which can increase costs.
Ultimately, there are many factors that can affect the cost of an injection molding project and it is important to consider all aspects before committing to a particular design or manufacturing process. By understanding each element, businesses can make informed decisions about their projects and maximize their return on investment (ROI). Additionally, working with experienced professionals who understand the complexities of injection molding can help ensure that parts are produced with optimal accuracy and quality while minimizing costs.
How To Reduce Injection Molding Costs?
1. Design for Manufacturing: Proper design of a part can reduce the need for post-molding operations, leading to cost savings. at Shanghai Elue, we provide strong engineering support about DFM, it means that we will help to check your designs and give right suggestions to simply your design to reduce cost. Yes it’s a type of free service as long as you provide us 3d files.
2. Optimize Gate Placement/Size: Strategically placed gates can help minimize material waste and improve cycle times.
3. Select Correct Material: Choosing the right material (or combination of materials) can help reduce costs while maintaining part quality. If you don’t have a preference on materials, tell us your products’ applications and we can suggest some based on our experience.
4. Consider Multi-Cavity Tooling: For higher volume parts, multi-cavity tooling should be considered as it can reduce cycle times and increase efficiency. The initial investment on tooling will be a bit more expensive, but it’ll significantly bring down the future production cost if you have a big demand about the parts.
5. Partner with Experienced Professionals: Working with experienced professionals who understand the complexities of injection molding can help ensure that parts are produced with optimal accuracy and quality while minimizing costs.
By following these tips and strategies, businesses can reduce their overall injection molding costs and maximize their return on investment. It is important to understand all aspects before committing to a particular design or manufacturing process.
Conclusion
Injection molding is a complex process with many factors that can affect costs. By understanding each element, businesses can make informed decisions about their projects and maximize their return on investment (ROI).
