Injection stretch blow molding is ideal for thin plastic containers like single-serving water bottles and 2-liter carbonated soda bottles, which are made from PET (Polyethylene terephthalate). In fact, since the 1970s, PET bottles like these have been almost exclusively manufactured through stretch blow molding.
Arlington Plastics Machinery offers a rotating inventory of stretch blow equipment including new, used, refurbished, and as-is. We have been a global leader in plastics manufacturing since 1987 and maintain our own warehouse stocked with inventory from the top names in stretch blow molding! You’ll find equipment from:
- Husky
- Nissei
- Krupp
- Sidel
- Side
- Cincinnati
Stretch Blow Molding Process
The stretch blow molding process can be broken down into one-step and two-step variations:
- One Step: The plastic preform is first made in the same machine and then rapidly cooled.
- Two Step: The plastic preform is created in a separate injection molding machine and then transported to a different machine.
In both cases, the cooled preform is reheated in the stretch blow machine. As
the preform is reheated, it is simultaneously stretched by a rod and air-blown,
which aligns the molecules bi-axially. (The neck and screw top remain in the
shape and location of the original injection.) The product lengthens and widens
at the same time until it fills the entire cavity of the mold.
Advantages of Stretch Blow Molding
The bi-axial orientation of stretch blow molding makes the resulting product stronger and more durable. With PET, this process also hardens the resin, which is what allows the plastic to maintain its dimension even under the high-pressure packaging of carbonated beverages. Compared to other methods, stretch blow molding also requires less raw material to create the same finished product.
Other benefits to stretch blow molding include:
- Preformed & Finished Bottle Neck
- Stable Product Quality
- Fast Production Speed
The trade-off of this type of molding equipment is the relatively high cost. Stretch blow molders are more expensive than other types of machinery, making them cost-effective only at very high production volumes.
We Can Buy, Sell, or Appraise Your Stretch Blow Molding Machines
No matter what you’re looking to do with stretch blow molding equipment—buy, sell, appraise, or refurbish—Arlington Machinery can help. We often carry machines from top brands like Husky and Nissei, and we have a team of product specialists on staff and ready to assist you.
Call us to find the right blow molding machinery for your production line, or fill out our online form to request a product quote now.
