How are Water Bottles Made? Plastic, Stainless Steel, and Aluminum

Promo Expert

Published: July 23rd, 2020

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? What about aluminum and stainless steel? 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.

A plastic water bottle is made by:

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.

Step 1: Into the Hopper

Small plastic pellets are put into a funnel-shaped contraption called a hopper.
Step 2: Dyed with Color

The pellets are flushed out of the hopper and mixed with a colored dye in the intended color of the water bottle.
Step 3: Pushed Through Heat

The dyed pellets are then pushed through a heated tube at about 150 to 350°F, which melts them down into a moldable goo.
Step 4: Injected Into Molds

The goo is then injected into molds that are in the shape of your water bottle and cooled down to harden.
Step 5: Second Round of Molding

After they're removed from the mold, the sports bottles are only small plastic cones without their distinct shape. They have to go through another round of molding before they're complete.
Step 6: Reheated

The plastic cones are reheated again so they're flexible and easy to mold into a new shape.
Step 7: Put Into a Larger Mold

The plastic cones are reshaped in a larger mold as air is forced up in the center, causing the bottle to expand into its desired shape.
Step 8: Cooling & Packaging

At the end, you're left with a beautiful water bottle ready to keep you nice and hydrated!

See the entire injection molding process in action!

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!

Injection 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

• Rigid

• Eco-friendly

• Slower turnaround

• Ideal for one plastic object

• Typically uses PP (polypropylene) or PS (polystyrene) plastic
Blow Molding

• 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

• Flexible

• More excess scrap material

• Faster turnaround

• Good for multiple plastic parts

• Typically uses PETE (polyethylene terephthalate) or HDPE (high-density polyethylene) plastic

• 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

• Rigid

• Eco-friendly

• 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

• Flexible

• 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.

– Paul Hanney, Sales Manager at Garyline Promotional Products

How are Metal Water Bottles Made?

Metal water bottles are usually made from aluminum or stainless steel. They're built to last, which means they follow a different process than the one used to create plastic water bottles.

A metal water bottle is made by:

Step 1: Small pieces of aluminum are stretched into a long cylindrical shape.
Step 2: Extra aluminum is snipped off the sides.
Step 3: The aluminum is shaped into the water bottles.
Step 4: An extra piece of metal is added to the top for the cap.
Step 5: An automatic cleaning station removes any extra lubricant or debris.
Step 6: The inside of the bottles is fitted with an insulating material.
Step 7: The bottles are heated and solidified in an oven.
Step 8: The exterior is spray painted in an aluminum coating or the chosen color.
Step 9: The bottles are reheated again.
Step 10: Once they're cool, the bottles are ready to be packaged.

Step 1: Forming the Cylinder

Small aluminum discs travel to a punch-press where they're stretched into a long cylinder by 660 tons of force.
Step 2: Chopping Extra Material

Excess aluminum is removed from the side of the water bottle by a mechanized blade. From there, it's sent down a conveyor belt and onto an aluminum wheel to be prepared for the next step.
Step 3: Shaping the Bottles

The aluminum cylinders are shaped into bottles. The machinery goes over the cylinder 26 times to draw the bottle's opening down to half its original diameter.
Step 4: Adding on the Metal

An extra piece of metal is added to the top of the bottle that's designed for the eventual cap. This will help the cap twist firmly into place on the bottle.
Step 5: Washing the Bottles

The aluminum water bottles go into a scrubbing station where all the excess lubricant and debris is removed.
Step 6: Lining with Polymer

After the water bottles are dried, they move down the assembly line where the inside is fitted with a high-tech polymer plastic via a spray nozzle. This is what gives the bottle its insulation.
Step 7: Firing in an Oven

The polymer is at first powdery but ends up solidifying after the aluminum bottles are placed in an oven that's heated to 365°F for 10 minutes.
Step 8: Painting

The bottles are spray painted in their sleek aluminum coating for a smooth, even finish.
Step 9: Reheating

Once the bottle is sprayed in the intended color, it's put again into an oven to solidify. The result is a smooth exterior on the aluminum water bottle.
Step 10: Ready for Drinking!

The whole process takes about 3 hours, with the final result being a nice, smooth metal water bottle for your hydrating needs.

Want to see the whole process in action? Check out this video from "How It's Made."

How are Water Bottle Lids Made?

No water bottle lid is made the same, but they're often made separately from the actual container. When it comes to the design, the lid goes through a similar process as the container.

For instance, at Garyline, a top water bottle vendor in the United States, the lids are designed on a digital screen and then molded by a machine. Some lids, depending on the structure, are shipped from overseas while others are made directly in the United States.

The design of the water bottle works hand-in-hand with the design of the lid. Measurements are taken to ensure that the cap screws on tightly and nothing leaks out. It's this kind of quality control that makes water bottles so easy to carry around during busy days.

How is a Design Added to Water Bottles?

How is the Design Added to Water Bottles?

Since many people carry water bottles around during the day, they're often printed with a name or logo and used as advertising items. Think of a school handing them out on college orientation night, a fitness center selling them to customers, or a non-profit using them at a fundraiser.

The logo or design is added to the exterior of the water bottle through a number of different techniques.

Screen Printing
A thick green goo called emulsion is spread over a screen, transferring your design onto the water bottle. This is the most common way to customize water bottles.

Full Color Printing
As the name suggests, the logo or design will be in full color. You can print as many colors as you need, without being charged an additional amount.

Laser Engraving
High-tech lasers etch your design onto the surface of the water bottle. This is often a great choice for stainless steel or aluminum options.

Pad Printing
A giant stamp is covered in ink and used to create a design on the water bottle. If you plan on printing one color on top of the other, this is a good option!

Why Advertise with Water Bottles?

No matter why they're used or how they're printed, custom water bottles are a great way to bring more awareness to any organization or event. The color possibilities are endless, and people actually use water bottles every day. This means a ton of exposure for your brand!

Stats for Success

On average, reusable water bottles last about five years.

A reusable water bottle can save the average American $6,180 in water after only five years of use.

The market for reusable water bottles is expected to reach $10.19 billion by 2024.

The Bottom Line

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!

Alyssa Mertes

amertes@qualitylogoproducts.com

866-312-5646 x 277

Alyssa is the Lead Copywriter at Quality Logo Products. As a promo expert, she's uncovered the world's first custom tote bag, interviewed the guy behind rock band ACDC's logo, and had a piece published by the Advertising Specialty Institute, a leader in the promotional products industry.

References

Beall, G. (2009, April 9). By Design: World War II, Plastics, and NPE. Retrieved October 8, 2018, from https://www.plasticstoday.com/business/design-world-war-ii-plastics-and-npe

Worth, J. (2017, July 13). Thermoforming vs. Injection Molding: What's the Difference? Retrieved October 8, 2018, from https://www.rodongroup.com/blog/thermoforming-vs-injection-molding

Keesler, C. (2014, September 22). Interesting Facts About Thermoforming. Retrieved October 8, 2018, from https://www.papublishing.com/2014/09/interesting-facts-about-thermoforming/

Indiana Bottle Co. (2018). 3 Differences Between Injection Molding and Blow Molding. Retrieved October 8, 2018, from https://indianabottle.com/3-differences-injection-molding-blow-molding/

Accutherm. (2015, January 26). The Importance of Temperature Control in Plastic Injection Molding. Retrieved October 8, 2018, from http://accutherm.com/blog/importance-temperature-control-plastic-injection-molding/

Divi. (2018). Injection Molding vs. Blow Molding. Retrieved October 8, 2018, from https://designtekplastics.com/tips/injection-molding-vs-blow-molding/

Penn State. (2017, October 10). Mathematics for Sustainability: Fall 2017. Retrieved October 9, 2018, from https://sites.psu.edu/math033fa17/2017/10/10/plastic-vs-reusable-water-bottles/

Transparency Market Research. (2016, October 21). Reusable Water Bottle Market to Reach US $10.19 Billion by 2024. Retrieved October 9, 2018, from https://www.prnewswire.com/news-releases/reusable-water-bottle-market-to-reach-us1019-billion-by-2024---new-research-report-published-by-transparency-market-research-597905681.html