How much does injection molding cost?

The plastic injection molding cost can reach 0.01USD per piece or even lower for high volume products, and 0.5USD per piece or even higher for low volume products.

This article will introduce in detail what the plastic injection molding process is and some of the factors that affect the plastic injection molding cost.

And finally injection molding cost examples to let you know calculating injection molding costs.

This article will help you decide whether plastic injection molding manufacturing processes is the right choice for your next project.

What is the plastic injection molding process?

Plastic injection molding is a process for making plastic products by filling an injection mold with molten thermoplastic material and then pumping it into the mold cavity.

It is also referred to as “thermoforming” or “injection molding”. The process involves injecting material, usually at high pressure, into a closed mold, which gives the product its shape.

This allows a large production quantities of injection molded parts to be made cheaply and efficiently.

Why can plastic injection molding costs be very low or very high?

Plastic injection molding requires injection molds to achieve, and we have to consider the plastic injection molds cost because they are usually very expensive.

For product size within 100mm and simple structure, the price of injection molds are usually 1000-3000USD, for larger size and more complex structure, the price of injection molds can reach 10000USD or more.

When the quantity of plastic parts is large, the price of the plastic injection mold manufacturing is very little when it is divided equally to each product, and when the quantity of products is relatively small, the price of the plastic injection mold is a lot when it is divided equally to each product. This is why the injection molding costs can be very low or very high?

What other factors also affect injection molding costs?

The quantity of the product is one of the factors affecting the cost of injection molding.

The injection molding cost also depends on the material of the product, the number of cavities of the injection mold used to make the product, the size of the product, the complexity of the structure of the product, the appearance and precision requirements of the product, etc.

How does the raw material of plastic products affect the injection molding costs?

The raw material of the product will have a great impact on the manufacturing injection molding cost, because the price of raw materials accounts for nearly half of the overall product cost.

In the design of products, we should consider the use of the product scenario, different products have different requirements for materials.

For example, food touch needs food-grade plastic materials, medical supplies, medical-grade plastic materials, electrical products need flame retardant plastic materials, outdoor products need cold, heat and UV resistance requirements, building structure products need to load-bearing requirements, indoor appliances need to look beautiful requirements, etc.

After understanding the plastic material requirements of plastic components, we need to know the classification of plastic materials to determine the price cost of plastic materials. Plastic materials can be classified according to the application of the resin into.

General purpose plastics

General-purpose plastic materials refer to a class of resins with large production, wide range of applications, good molding and processing, and low cost.

Specific varieties include polyethylene, polypropylene, polyvinyl chloride, polystyrene, phenolic resin, amino resin, unsaturated polyester and epoxy resin, etc. General plastics are mainly used in packaging, construction, agriculture and daily use.

Engineering plastics

Engineering resin materials refer to a class of plastics with good mechanical properties, high dimensional stability, and can be used at higher temperatures.

It has properties close to those of metals and can be used in structural products such as machinery, electronics, automobiles and aviation.

General plastics

General plastic materials refer to a class of plastics with low dosage, low application range and general performance.

Mainly including polymethyl methacrylate, polyurethane, fluoroplastics and chlorinated polyether, etc.

Special plastics

Special plastic materials refer to a class of plastics with unique performance, high price, low production and narrow application range.

Mainly including heat-resistant plastics, barrier plastics and conductive plastics, etc., specific varieties of polyphenylene sulfide, polysulfone, polyimide, polyaniline and vinyl alcohol copolymer, etc.

How does the number of injection mold cavities affect the cost of injection molding?

For example, for a 100T injection molding machine, the injection molding processing cost is 15USD per hour, and the injection molding machine cycle is 30 seconds. The injection molding manufacturing costs is 0.0078USD per product for a 16-cavity plastic injection mold.

For projects with large production volume of products, the injection mold cavities can be considered to be as large as possible, but the injection mold cavities is not the more the better.

However, it is not better to have more injection mold cavities, because for the same product, the more injection mold cavities, the higher the manufacturing injection molding tooling cost, and the more the average price of each injection molded product. 

There is also a limit to the mold size that each injection molding machine can accommodate.

Therefore, for large quantity of injection products, it is better to make as many cavities as possible within the size of the injection molding machine, so as to reduce the injection cost, it’s a cost effective solution.

How does the size of the product affect cost of injection molding?

The larger the product, the more raw materials used, so the higher the cost of raw materials.

The larger the product, the larger the size of the injection mold, the higher the injection mold costs, and the higher the average price spread to each product.

The larger the product, the larger the injection mold, the larger the tonnage of the injection molding machine required, and the higher the processing cost.

The larger the product, the longer the injection molding cycle, and the higher the processing cost.

In addition, the larger the product, the higher the packaging cost and the higher the transportation cost, all the factors will affect the cost of the product.

How does the structure of the product affect the cost of injection molding?

Products with complex structure require some complex injection mold structures to be realized in the injection mold.

Such as screw structure, slider, inserts and other structures, which will increase the injection mold cost, and the cost of the product will increase when it is spread to the injection molded products on average.

The complex structure of the product, injection molding cycle longer, which will affect the processing cost of the product, the production costs will increase.

How do product appearance and tolerance requirements affect injection molding costs?

Products with high appearance requirements require special packaging to protect the appearance of the product from being scratched during packaging and transportation, which will increase the packaging cost and transportation cost of the product.

Products with high tolerance requirements require the injection molding factory to increase the workload of dimensional accuracy control, for example, the factory’s quality inspectors need to conduct tolerance spot checks on the products every one hour to ensure that the precision of the products is within the required range.

How is the cost of injection molded products calculated?

Let’s take a 0.05kg weight product, a 4-cavity injection mold, a 30-second injection production cycle, a 150T injection molding machine, and a 15USD/hour processing fee as an example, and analyze in detail how the cost of an injection molded product is calculated.

The cost of injection molding products=raw material price+processing cost+packaging cost+injection molding factory profit

Raw material price: For example, the current market price of conventional PP material in China is 2usd/kg, so the raw material price of the product is 0.05kg*2usd/kg=0.1usd.

Processing cost=15usd÷3600 seconds×30 seconds÷4=0.031usd.

Packaging cost: conventional five-layer export corrugated carton, each box of products a large PE bag, packaging costs about 0.01usd

Factory profit=(0.1usd+0.031usd+0.01usd)*0.3=0.042usd

The total cost of the manufacturing injection molding product=0.1usd+0.031usd+0.01usd+0.042usd=0.183usd.

Of course, each factory’s injection molding machine processing cost and profit is different, so the price is also different.

The above calculation gives you a detailed understanding of the cost of manufacturing injection molded parts, and the next time you do an injection molding project, you can calculate the cost of the project in advance to decide whether to use injection molding for your next project.

Conclusion

Now that you know what aspects affect the injection molding cost, you can save your injection molding product cost by optimizing these aspects when designing injection molding products.

If you are not very professional in this area, you can get Zetar to help you from product design to finalizing the whole injection molding project.

With Zetar, you can have your project come true in a matter of days. With more than 20 English-speakers and 7 experienced engineers on hand to support the process from idea to reality – let us help turn your dream into a reality! Contact us for great supports.