Injection Molding vs. Blow Molding Techniques – What are the Differences?

The injection molding and blow molding techniques are two most common and popular plastic molding production methods you can use in your manufacturing production. These methods are suitable for various industrial applications, and both of them have their own uses. Let’s delve deeper into the differences between injection molding and blow molding techniques.

Injection Molding Technique – What is It, Benefits, and Applications

The injection molding technique is a manufacturing process that allows you to create plastic products by injecting heated plastic materials into the mold. The heated plastic will fill the mold to assume the mold’s shape. Then, you will need to cool the plastic materials down before you can reject the final products from the mold.

Here are the biggest advantages of injection molding:

• This manufacturing technique provides you with a high level of repeatability. You can still get similar results from repeating this production technique.
• Plenty of material options are available to use, which include elastic and solid plastic materials. There are also various grades of the plastic materials for you to choose.
• You can apply various different details on each product you create with this process, including those that contain intricate geometries.
• The plastic injection-molded products don’t require post-processing, but it might enhance the final product’s aesthetics.
• This production technique allows you to produce large numbers of plastic-molded products with the fastest production time.

Here are some common applications of the injection molding technique:

• You can create cases and containers for various products and appliances, such as the ones used in the consumer electronics and food & beverages industries.
• Various medical tools can also be produced with the injection molding technique, which can help patients feel at ease when they receive treatments from healthcare professionals.
• Dashboard, engines, and exhaust systems of vehicles are often made with injection molding of plastics, allowing manufacturers to produce both durable and elastic components for their vehicles and other automotive-related products.

Blow Molding Technique – What is It, Benefits, and Applications

The blow molding technique is the production process you can use to manufacture plastic parts that have hollow shape inside their body, such is the case with plastic bottles or buckets. With this production method, you can create objects that you can use as containers in various industries, including food & beverages, household products, etc. 

Here are the benefits of the blow molding technique:

• When creating the hollow plastic products with handles, you can also include the handle design in your blow molding mold, so you don’t need to perform the molding process twice.
• The costs for the molds or tools will be quite inexpensive, so you can produce plenty of hollow plastic products as much as you need.
• The blow molding technique is capable of producing high-volumes of hollow plastic products at the fastest rate.
• You can also create complex parts for the hollow plastic product design you are working on, with tolerances that are quite tight.
• The overall production process of blow molding is fast and low-cost.

Here are the most common applications of the blow molding technique:

• Plastic bottles in the beverages industry, with various intricate designs and branding that companies can apply to them.
• Food containers in various shapes and sizes, which can have cylindrical or square designs.
• Children’s toys that have hollow shapes in them, which can usually be squeezed.
• Various hollow-type components for certain products and appliances across a wide range of industries, such as hoses and similar-shaped items.
• Various hollow-shaped containers for skin and hair care products, such as shampoos, conditioners, face wash, hair serum, and many others.

Key Differences between Injection Molding and Blow Molding Techniques

Both injection molding and blow molding techniques have the same goal, which is to create plastic-molded products based on the mold that you are using in your manufacturing production. But, both techniques have their differences.

Here are the key differences between injection molding and blow molding techniques:

• Solid objects vs. hollow objects. The injection molding technique is used for creating solid plastic objects, whereas the blow molding technique is used to create hollow plastic objects. Both methods are suitable for use in various industrial applications and both offer the flexibility in creating intricate designs. 
• Injection vs. extrusion/blow. Injection molding injects the heated plastic materials into the mold using high pressure. Meanwhile, the blow molding technique will blow or extrude the heated plastic materials into the mold using compressed air.
• Thick vs. thin walls. You can create thick-walled plastic products with the injection molding technique. Meanwhile, the blow molding technique can only create thin-walled plastic-molded products. You can’t use blow molding to create the solid, thick-walled items, whereas you can use injection molding to create both solid, thick walled items and solid, thin-walled items. The injection molding technique is not suitable for creating hollow plastic products.
• More expensive vs. less expensive costs. In general, the injection molding technique will be more expensive to do compared to the blow molding technique. Injection molding uses more plastic materials and more heavy-duty equipment, which are the factors that make it more expensive to perform.
• Final product durability differences. Because of the hollow parts of the plastic items produced by the blow molding technique, the final blow-molded products will usually be less durable than the injection-molded products. The injection molding technique can produce solid products with thick walls that are durable, strong, and more suitable to use for long-term.

Conclusion

Both injection molding and blow molding techniques have their own processes and usage applications in various industries. So, you can’t say that one method is better than the other. You will need to utilize both injection molding and blow molding techniques for various manufacturing production projects that you have. These production techniques will go hand in hand to complete each of your manufacturing goals in your industrial application.
TEAM Rapid provides a wide range of plastic injection molding services, including the injection molding and blow molding techniques, for various industrial applications based on your project needs. You can consult with us about what you need to achieve in your manufacturing projects, and we will send you a quote explaining the project’s manufacturing plans and costs to you.