Find out more about the steps behind custom plastic blow molding!

1. Blow Molding: How It
Works

2. Advantages of Blow Molding
Blow molding technology is borrowed from the glass industry, with which plastics
compete in the recyclable or disposable bottle market.
Depending on the part that needs to be created, one type of molding may be preferable over another.
Advantages of blow molding include less time spent on the mold-creation process and faster turn-around
times by a custom blow molding company.
Blow molding is well suited for high production rates using a variety of materials. Blow molding tools are
also fairly inexpensive compared to other molding equipment, so more companies are able to perform
custom plastic blow molding with custom blow molds.

3. Blow Molding Steps:
Blow molded parts are only manufactured from thermoplastics, most often from Polyethylene; it has a
high density and molecular weight ideal for blow molding. The blow molding process involves a
number of steps, simplified in the following list.

4. 1. Storage
Plastic in granular, pellet form is stored in a hopper for future use.
To find out more about customizable bottles and plastic containers for your
business, talk to the experts at Streamline Plastics.

5. 2. Heating
The plastic granules are fed through a heated section of a blow molding
machine.

6. 3. Forming
The plastic granules melt into liquid which is formed into parisons.

7. 4. Blowing
Pressurized air is forced into parisons which forces the plastic to the sides of
the blow molds, making the shape of the bottle or plastic part. Read the full
details of the custom blow molding process here.

8. 5. Cooling
The bottle is cooled and released from the mold.
The distinctive part of the blow molding process is the plastic parison. The parison is a tube-like piece of plastic with a hole at one
end, shaped much like a test tube. Through the hole, compressed air can pass into the plastic parison. The parisons are clamped
into blow molds and air is forced into them, which pushes the plastic out to match the molds. This is why the process is called blow
molding.

9. Blow Molding versus Injection Molding
Blow molding and injection molding are very different procedures that are capable of producing significantly different products.
Blow molding products usually consist of hollow bottles, whereas injection molding products can be any type of plastic product
from a plastic bead to a car door panel.
Blow molding products rely on pressurized air for creation; this creates uniform parts that may or may not have seams. Injection
molding only uses poured molten plastic to create its products. Blow molding also relies less on mold making to determine the
strength of the part than injection molding does.
Blow molds usually only determine the exterior form of the product. Injection molds have to include every facet of the product,
such as wall thicknesses, center shapes, and any other important attributes, making the mold more than 90% of a part’s success.
Using the different blow molding processes for blow molding plastic bottles all essentially create plastic bottles, but each method
may take different equipment. Some blow molding companies, such as Streamline Plastics, may also be able to perform custom
blow molding. Custom blow molding products may consist of special bottle styles, added logos, colored bottles and various plastic
choices.

10. Streamline Blow Molding Offers Custom Plastic Blow Molding
Streamline Blow Molding, a Streamline company, has all the equipment and manpower to create
exceptional blow molded products. They offer customized options for blown products such as logo
inclusion and color changes. Streamline Blow Molding is proud of their clean processes, recyclable
materials, and fast production.
For a quote on your next blow-molded product, contact
Streamline Blow Molding today at 801-782-3660 or visit
www.streamlineplastics.com.