How HDPE Bottle Annealing Units Work

How HDPE Bottle Annealing Units Work

Factories that use HDPE (high-density polyethylene) to manufacture HDPE plastic bottles will need a bottle annealing unit. Since we are an annealing unit manufacturer, we often get asked how annealing units work. This blog post will explain how annealing units are able to improve your factory’s productivity so you can make an informed decision for your company.

How do annealing units work?

Immediately after plastic bottles are blow molded, they are conveyed into the annealing unit. Once inside the annealing unit, the bottle is rotated 360 degrees so the plastic is completely heated. The high temperature causes the containers to shrink up to 2.5% before being cured to the proper mold size. The neck rails for the annealing unit are cooled with water to protect bottle neck finish and ensure the bottle necks don’t warp into ovals from the heat.

When the bottles emerge from the other side of the heat tunnel, they are ready to be immediately filled or stored. Since the HDPE bottles are immediately ready to be filled, this can reduce how much storage space you need for bottles.

What are the benefits of annealing units?

While HDPE is commonly used to manufacture plastic bottles, it’s also a brittle material until it enters an annealing unit. Annealing units soften plastic by heating the material to a certain temperature before cooling them down. The annealing process shrinks HDPE bottles down to a consistent size for immediate filling or storage. Since the bottles don’t need off-line curing, this saves you time and money. Otherwise, you would have to designate a space in your facility for curing plastic bottles.

Annealing units shrink and cure plastic bottles so you end up with consistent bottle sizes for filling. This means that you don’t have to worry about under-filling an oversized bottle or over-filling an undersized bottle. Annealing units ensure bottle sizes are consistent with the mold design, which eliminates waste.

Does my factory need an annealing unit?

We recommend an annealing unit for any factory that manufactures HDPE bottles or other containers (like milk jugs). HDPE is a brittle material prone to breaking, unless it is run through an annealing unit. You will also eliminate the waste that comes from over or under-filling bottles that are not consistent sizes.

Who do I hire to install annealing units?

You’ll want to look for an experienced factory equipment manufacturer. Be sure to ask about their past clients to see if they have experience working with your industry and the types of factory equipment you use. For example, you want to make sure that you aren’t the first client the company has had from the food and beverage industry. The right company will be able to install and integrate an annealing unit with your current factory conveyor system.

Automation Ideas is a conveyor system manufacturer dedicated to helping factory owners install equipment designed to improve efficiency and eliminate waste. If you are interested in learning more about annealing unit installation, give us a call at (877) 254-3327.