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How Aluminium Bottles Are Made: From Slug to Sleek Containers

Aluminium bottles are becoming increasingly popular in a variety of industries due to the  lightweight, durable, and recyclable nature of the material. But have you ever wondered how these versatile containers are actually made? Trust us when we say, it’s a fascinating process! The process begins with a simple piece of aluminium called a slug. Here, we’ll take a step-by-step journey from slug to finished aluminium bottle.


Step 1: The Slug

A slug is a piece of aluminium that has been stamped or pressed from a roll of aluminium sheet or coil. It is essentially a blank that will be transformed into a bottle. The aluminium used is usually a mix of new and recycled material.

Step 2: Extrusion

The slugs are lubricated and the slug is placed under a press. The press forces the slug through a die, a process known as cold extrusion. This creates a long, cylindrical shaped container.

Step 3: Trimming

The top of the bottle is usually a bit irregular. To solve this, the bottle goes through a trimming process, where excess material is cut away to leave a clean, even edge.

Step 4: Cleaning and Washing

After trimming, the bottles are cleaned to remove any oils or residues. They are washed using a cleaning detergent with hot water, and then put through a drying oven to prepare the coating process.

Step 5: Inner coating

An inner lacquer is applied in the aluminium bottle (base epoxy phenolic or polyester lacquer) and the bottles are taken through a drying oven for second time.

Step 6: Coating and Decorating

Before decorating, a base coat is applied to the aluminium bottle to ensure that the subsequent layers of ink and design will adhere properly. The bottles are then decorated with an indirect printing-technique, additional silk screen printing is possible in a separate process, based on the desired design and finish.

Step 7: Overlacquering (transparent)

To protect the printing the aluminium bottles are overlacquered with a transparent lacquer (glossy or matt).

Step 8: Necking

To create the bottle’s neck (the narrower opening at the top), the bottle is subjected to a process called ‘necking’. This involves a series of tools that gradually reduce the diameter of the bottle’s opening to the desired size.

A concave base is formed at the bottom of the bottle to give it stability when standing. This is done using a special tool that shapes the bottom of the bottle.

Step 9: Inspection and Packaging

The final step involves a thorough inspection of the bottles to ensure they meet all quality standards. Once they pass inspection, they are packaged and prepared for shipping to customers.



The production of aluminium bottles is a fascinating process that marries advanced technology with sustainability. Starting from a simple aluminium slug, a series of intricate and carefully controlled steps are performed to transform it into a sleek, lightweight, and recyclable aluminium bottle. Explore our range here.

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