Blow Molding vs Injection Molding

Blow Molding vs Injection Molding

When looking for the perfect product parts, making the correct decision for your manufacturing method is extremly important. Injection Molding and Blow Molding are two of the most common production methods. Both of these got some advantages over the other one. In this article we will dive deeper in both options so you can make the best decision on which process is perfect for your parts.

Injection Molding

The Injection molding process starts with melting the plastic material and injecting it into the membrane cavity. Once the molten plastic enters the mold, it is cooled and molded into the
required shape. The resulting shape is often the final product part which doesn’t need much further processing (surface finish is normally included in the mold design) before it is installed or constructed to an end product.

Many details, such as bulges, ribs and threads, can be molded in
a one-step injection molding process. The equipment of the injection molding machine has 2 essential parts: the injection device and the forming device for melting and feeding the plastic into the mold. Controlling the molding device has 2 crucial steps:


1. The mold needs to be closed under pressure.

2. The next step is to control the pressure and speed to inject the melt into the mold.


There are two types of injection devices: screw-preplasticizer or two-stage device with a reciprocating screw. The screw-type preplasticizer uses the preformed screw (stage 1) to inject the molten plastic into the injection rod (stage 2). The advantage of the screw-preplasticiser is that the melt quality is constant, high pressure and high speed, and precise control of the injetion quantity is possible (using the mechanical pressure device at both ends of the piston stroke). These strengths are required for transparency, thin-walled products and high production speeds. The disadvantages are inhomogeneous residence time (resulting in degradation of materials), higher equipment costs and maintenance costs.s 

Blow Molding vs Injection molding

Feel free to

request a quote!

Blow Molding

Blow molding is a manufacturing method widely used within the plastics industry to make strong, hollow containers. Some examples of products commonly made through this process are fuel tanks, plastic drums and PET bottles. A typical blow molding process involves melting plastic in a hollow tube, also known as a parison, placing the tube between the halves of a mold and pumping air into the mold under pressure until it expands to fit the shape of the mold; the two halves of the mold then separate and release the finished (end) product.

The Blow Molding trend started in the late 1950s, with the birth of high-density polyethylene and the development of a blow molding machine, blow molding technology became widely used. The volume of hollow containers can reach thousands of liters, and some are automated. It is suitable for blowing plastic with polyethylene, polyvinyl chloride, polypropylene, polyester and many other polymers (for an extensive list of manufacturing materials see our Materials page).

Don't know which method to use for your manufacturing process? Take a look at our downloadables!

Blow & Injection Molding At Production Heroes

As a manufacturing company, Production Heroes priority is to manufacture high-end sustainable products. Blow Molding and Injection Molding are  frequently used production methods used by consumers and companies to manufacture plastic products. Budget-Molding works with the best manufacturing partners all over the world. You can find some of our injection molding products you can find here. (Higo, Kitty Kasas and Alleovs).

When you’re looking for a high-end product manufacturer feel free to contact us we give you the right guidance all the way through, our communication is transparent and frequent. Besides being a reliable manufacturing partner our expertise goes further. We got two dozen professionals on our floor who got over 20 years of experience in designing, engineering, and manufacturing. We can guide your innovation to greatness. Feel free to contact us.

                    See More Production Heroes: