Views: 39 Author: Site Editor Publish Time: 2020-09-15 Origin: Site
You bring a water bottle to work, the gym, and out running errands on weekends. If you have kids, they bring one along to school and baseball practice. Have you ever stopped and wondered how this essential piece of drinkware is made? A lot more goes into the process than you may think!
How are plastic water bottles made? Bottles up! It's time to learn all about the manufacturing process for your favorite drinkware.
How are Plastic Water Bottles Made?
Reusable plastic water bottles are made using a variety of different plastics including PVC, polypropylene, and PET. Some are BPA-free, while others contain chemicals that could be harmful to your drinking water.
Step 1: Plastic pellets are fed into a hopper.
Step 2: The pellets are dyed with colored ink.
Step 3: The colorful pellets are pushed through a heated tube, which melts them down.
Step 4: This melted goo is injected into molds.
Step 5: The plastic goes through one more round of molding.
Step 6: The plastic is reheated so it's flexible.
Step 7: The plastic is shaped into the water bottle.
Step 8: The plastic is cooled, the lid is created separately, and the water bottle is ready for packaging.
What is Blow Molding?
Blow, or rotational molding, is another way to make plastic water bottles. This is when manufacturers use thermoplastic polymers and pressurized air to create hollow objects like bottles and containers. The process was inspired by the ancient technique of glass blowing and is broken down by either extrusion, injection, or stretch blow molding.
Extrusion Blow Molding
This is used for a higher production of sports bottles, which often also includes filling and labeling the bottles.
Injection Blow Molding
This process is similar to injection molding, where a melted down polymer is injected into a preformed mold and blown out from a tube called a parison. It is often used for medical or single serve bottles.
Stretch Blow Molding
The plastic is stretched out and then expanded by the blowing process. The end result is a plastic bottle that's extremely durable.
Every manufacturer uses a different system for blowing out the plastic. No matter what, though, they all result in an awesome water bottle that's ready to be filled!
Here is the differences between the injection molding and blow molding:
• Melted plastic is injected into the mold under intense pressure until it forms the shape of the water bottle
• Excess air causes bubbles or abnormalities
• About 90% of the production time
is dedicated to making the mold
• Higher cost
• Slower turnaround
• Ideal for one plastic object
• Typically uses PP (polypropylene) or PS (polystyrene) plastic
• A plastic tube called a parison is heated and filled with air; the mold is clamped around the parison until it takes the shape
• Air is crucial to the process
• About 50% of the production time is dedicated to making the mold
• Lower cost
• More excess scrap material
• Faster turnaround
• Good for multiple plastic parts
• Typically uses PETE (polyethylene terephthalate) or HDPE (high-density polyethylene) plastic
Blow molding and injection molding are great ways to create water bottles because they allow you to control every step of the process and for it to run efficiently for long periods of time.
Whether you use a plastic or stainless steel option, and whether it's customized or blank, your water bottle is just as important as your phone, car keys, and wallet when you leave for the day. Take the time to appreciate all the craftsmanship that goes into your favorite drinkware!