Injection molding is one of the most productive processes wherein a molten material is injected into molds to create intricate parts, and components. Conventional technology typical of high volume manufacture has always been used in injection molding and hence suitable for any bulk manufacturing. In recent years however, low volume injection molding has attracted attention especially for industries that use small production lots or those which want to create prototypes. Low volume injection molding does not take long to set up as it does high volume injection molding making it preferable in some quantity production. This makes it essential for injection molding manufacturers to understand the two modes of production so as to eliminate the loss that often comes up due to wrong economical and efficient means of production for a specific production run.
Overview of Injection Molding
One of the most widespread manufacturing processes is injection molding where the thermoplastic material is heated and injected into an existing thermoplastic mold-cavity to create finished parts. In the process, thermoplastic pallets are first placed into a hot barrel. After it is heated, the melted substance is then pressed into an injection-mould chamber. In particular, injection molding equipment exerts hydraulic force to form the thermoplastic material into the appropriate form. There, the molten thermoplastic dries and sets into the desired shape. This part is then released after the mold is already cold and the core has opened up.
The injection molding process is very precise and reproducible which makes it suitable for complex design of premium parts. It is adaptable and works with thermoplastics, elastomers, and composites. That adaptability is why injection molding is used extensively in industries like automotive (dashboard and bumpers), healthcare (syringes and diagnostics) and consumer goods (packaging, electronics, toys).
What is Low Volume Injection Molding?
Low volume injection molding is an injection molding technology used to make a limited quantity of plastic components. This is a different process from traditional injection molding which is designed to make a large volume of parts. It’s especially suitable for small batches as high numbers make the expensive molding equipment unprofitable.
The cost savings of low volume injection molding, in comparison with the big volumes of mass production, is a major benefit of this process. It also decreases the design to manufacturing cycle by a large margin since less setup is needed which accelerates the design to product. This is why low volume injection molding is only used in prototyping, testing or niche products.
Low volume injection molding is a process of great advantage to startups/small companies as you can create parts or products in limited run or test the market and go to mass production. Moreover, the automotive, medical device industry and other businesses that need special parts or prototypes can easily manufacture them using low volume injection molding.
What is Traditional Injection Molding?
Traditional injection molding entails large scale manufacturing processes of plastic parts, which can run into thousands and millions of parts. This approach is aimed towards large production runs where the mass production economics optimizes the cost of each part. The process involves producing a mold that will be used monotonously or repeatedly to create the same part to a near exact specification. The initial cost outlays for traditional injection molding are very high, but when this is taken over a large batch production, the price for each part produced is extremely low, thus being very economical on mass production.
One of the fundamental advantages which traditional injection molding technology has is the rate at which large batches of parts can be produced. This technology in particular suits industries with such requirements, like the consumer electronics industry, in which thousands of the same housings, connectors and buttons are produced or the automotive industry which injects molds for bumpers, dashboards and other interior trims.
Key Differences Between Low Volume and Traditional Injection Molding
Cost Structure
Low volume injection molding is cheaper initially since the tooling costs are lower as compared to the traditional injection molding making it suitable for companies that may have low demand in the molding market. Still, the cost per part can be higher than that of traditional injection moulding due to the larger number of parts produced in a cycle which do not optimise economies of scale. On the other hand, traditional injection molding which involves production of molds requires huge costs in tooling, but the cost for each part is rather low in large scale production. While it applies to all industries, for mass production, the price per part significantly decreases hence making traditional molding cheaper.
Production Speed
Low volume injection molding has shorter mold and set up times with molds being less complex therefore making them more favorable for smaller or rapid production. On the other hand, molds required in the production of automotive products are usually more complex which complicate the testing and adjustment process increasing set up time.
Application Scenarios
Low volume injection molding is best used for prototype and development, for testing, for special order parts, or to create small batches of components and parts specific to a particular industry that needs very limited quantity. You should use it for a startup or limited release and it is generally cheaper than mass-production. Traditional injection molding is suitable for mass production where the same component is produced in large batches such as automotive components, consumer electronics, or any other massive business.
Flexibility
Low volume injection molding is more flexible than high volume injection molding because the modifications can be made very easily on the mold and also in the design of the product injected. This is especially helpful for organizations that are doing prototyping or producing something that is going to get modified a lot. Traditional injection moulding is a bit more immobile in shape, as massive forms of moulding can be quite expensive to adjust, so is best for stable designs that can be made for many years, with no design changes between.
Material Options and Mold Longevity
Low volume injection molding is compatible with a larger selection of plastics and composites which provides greater flexibility in materials used. The downside of this however, is because they use simpler molds that allow for low-volume production, the molds have a shorter expected life. That being said, the molds that are needed for traditional injection molding (for high-volume runs) have to be much tougher and more durable. They are made to withstand the pressures of mass production and be used multiple times. Because of this, they need to be made from expensive specialist materials and the initial cost is therefore higher.
Conclusion
Both low volume and traditional injection molding methods have their pros and cons, depending on the production requirements. Low volume injection molding is most suitable for prototyping, small production, and testing the design and material variation of a product. It is used for short runs for it is more efficient and economical but the price per unit item is relatively high. On the other hand traditional injection molding is advantageous in that it is cheaper in the long run for large production volumes where large quantities are needed, mold robustness. However, this approach requires a greater amount of capital to be invested initially and also takes a lot of time to set up. All in all, the amount, time and costs remain a decisive factor in settling for either of these two counter methods. Therefore before deciding on the right and proper methods for your project, it is wise to consult other experts or an experienced injection molding manufacturer. Contact us to get more details on which of the methods to use in your project.
