5 Advantages Of Injection Molding

Injection molding speed for bottle caps
Injection molding speed for bottle caps
Resource: https://youtu.be/vsJzM_NjU_k

For many manufacturers, the many advantages injection molding make it an option for manufacturing parts and components. From design to manufacture, the benefits are numerous. This post goes over the five major advantages of injection molding. It also covers some of the disadvantages that it can come with.

Injection Molding Manufacturing

Injection molding manufacturing involves melting a polymer (or a mix of polymer and metal or glass material) and injecting it into a mold. So why is injection molding good? Well, the process is relatively fast and efficient, and an ideal choice for mass production.

Because it involves the use of low-cost plastic materials, including recycled plastic, injection molding offers a cost-effective method of manufacturing and creating parts and components. Other advantages of injection molding are given below.

Low-cost injection molded enclosure for sawing tool
Low-cost injection molded enclosure for sawing tool
Resource: https://www.researchgate.net

Advantages of Injection Molding

If you’re looking to use injection molding to create your parts and components, the first thing to consider is how the technique can benefit you. So, why use injection molding. There are many reasons why you would want to: Check out these five of the most significant benefits that the process offers:

1. Advantage #1 Cost of Injection Molding

The cost of injection molding, save for the cost of making the mold, and which is only a one-off cost, is actually quite low. This cost per unit is comparatively much lower than that of several other manufacturing processes, which makes injection molding an attractive option.

For example, the injection molding process mostly uses plastic. The price of plastic is relatively low, and when coupled with the injection molding method of production, makes for a cost-effective solution. Also, the process of injection molding itself wastes very little material, helping to keep costs down.

2. Advantage #2 Injection Molding Materials

Injection molding allows for a wide variety of materials to be used. This includes thermoplastics, elastomers, thermoset polymers, and metals or even glass. Depending on the product requirements and design needs different material types can be used.

Besides the many options, injection molding materials can cost as little as few dollars or even less than a dollar per kilogram. Polystyrene pellets for injection molding, for example, can cost as little as $1.50/kg. Other injection molding pellets cost more or less, but overall the price of materials is quite low.

3. Advantage #3 Injection Molding Speed

Depending on the type of machine, part thickness, material and other factors, the process to produce a single product in the injection molding process can be as little as 5 seconds to 30 seconds or slightly more. Large parts with thick walls take longer, while smaller parts like injection molded bottle caps take shorter times.

With the use of multi-cavity molds, multiple copies can be produced in in a single operation. This speed allows for high production capability and increases the efficiency of mass production efforts; more units produced in less time. This makes it ideal for companies that require large numbers of components.

4. Advantage #4 Injection Molding Tolerances

The even distribution of temperature and pressure throughout the mold cavity, combined with the accurate control of injection speed, make it possible to create parts with tight tolerances; this is another of the many advantages of injection molding, and which makes it suit applications that require precise measurements.

Depending on the type of part and its size, injection molded tolerances can be as precise as +/- .005 inches. Compare this to other processes such as blow molding, which come with much less precise tolerances, and you can see why injection molding is a preferred method for many applications.

5. Advantage #5 Injection Molding Efficiency

One of the most remarkable advantages of injection molding is its efficiency in terms of material usage. This is because injection molding eliminates the need for extensive material cutting or extra processing, plus the little trimmed material can be reused or sold to other manufacturers.

Another advantage of injection molding is that almost all used materials are recyclable, meaning minimal environmental impact and a much more sustainable production cycle.

Furthermore, it allows for the use of post-consumer recycled materials, allowing for more efficient use of resources. This also reduces production costs as well, as manufacturers can avoid purchasing large amounts of virgin material.

Plastic injection molding process
Plastic injection molding process
Resource: https://www.designworldonline.com

Injection Molding Disadvantages

Although injection molding has many advantages, it also comes with some disadvantages. These must be carefully evaluated and the best decision made based on the requirements of the product. The disadvantages of injection molding include the following:

High Tooling Cost

The cost of injection molding can be very high, but only initially. This includes the cost of making the mold, which often ranges from tens to hundreds of thousands of dollars. Additionally, there are costs associated with minor adjustments that may have to be made throughout the production process.

That being said, the process is well suited for mass production scenarios. Short runs may not be cost-effective, as the setup costs and tooling availability must be taken into consideration. As such, injection molding cost comes out significantly lower once production runs go beyond 10 000 units or so.

Long Lead Time

The lead time, or the time needed to produce a product, can be quite long with injection molding. This is due to the fact that the molds must be made and tested before production can begin. As such, it can take weeks or even months for products to be produced using this process.

For long-term projects, though, the lead time is well worth it, as injection molding yields high-quality and repeatable products that can be made quickly. Many injection molding solutions also offer engineering techniques that can shorten the lead time by optimizing and streamlining the entire process.

These are some of the disadvantages of injection molding. While these may be seen as drawbacks, it is important to note that they can be overcome with careful planning and consideration of the project requirements.

With that said, many companies find that the advantages far outweigh any potential drawbacks, making injection molding a reliable and cost-effective process for their projects.


There are many reasons why injection molding is used in many applications today. We hope that this article has been helpful in giving you an understanding what the process offers. If you are considering injection molding, ensure that you make a careful analysis of its pros and cons in relation to your project needs.

Table of Contents
Latest Posts
Contact Us