Anatomy of a Can

By: Berlin Packaging Specialist
Date: October 20, 2019

 

Why Metal?

Metal is one of the world’s most abundant raw materials, superior content protection and boast a very low environmental impact.

Types of Metal Liners

  • C-Enamel liner works with low acidic foods “Think C is for Corn.” For prolonged stored foods with low acidity, but have the ability to discolor a raw metal can surface.
  • White Enamel liner works with higher acidic foods “Think Red”, like beets, berries, tomatoes, etc.
  • Epoxy liner is suitable for most latex and water based solvents and increased chemical compatibility.
  • Laquer liner is FDA approved and for more acidic foods and aggressive solvents.

FAQ's About Metal

Heated:

Tinplate can be heated up 450°F (230°C). Carbon and Stainless Steel can be heated up to 2600°F.

Rust:

Much of our metal is treated with a rust inhibitor, but not rust preventer. Rust is based on moisture and oxygen and however much exposure a container gets to either one of these post manufacturing is what will determine if any, how much rust you will incur. Testing is recommended with your product.

Terms at a Glance

Terms at a Glance

Bead:

Concave (interior bead ) or convex (exterior bead ) area usually 1/8" wide spanning the circumference of the tin to provide additional strength and stability to the tin body

Curl:

Area of tin turned in on itself to provide a safe, finished curved edge

Drawn:

See seamless

End:

The area of a tin also known as the bottom. Coffee-style hermetic tins generally have two ends. Ends can be attached by seaming them on or crimping

Hem:

similar to a curl, an area of tin turned in on itself to provide a safe, finished flattened edge

Lock-seam:

Side walls meet and attach by hooking onto one another to form a tin body

Seamless:

A tin that is constructed from a single piece of tin drawn to form the body of the can

Stepped cover:

Type of slip cover in which a “step” is created between the horizontal surface and vertical surface of the cover so that stacking tins is possible with less likelihood of toppling over

Welded Seam:

Seam type in which side walls attach to one another through the use of heat to form a tin body

Body:

A can without a cover (lid); the base of a container

Cover:

A can’s lid or closure

Dome:

A type of cover characterized by a flat horizontal surface (top) that tapers smoothly onto the skirt (vertical surface)

Full friction:

a plug-style metal cap fits snugly to the interior of the can

Interior Friction:

Cover/closure option in which a pliable ring fits to the interior of a tin allowing for a straight-sided slender profile can

Multiple friction:

A plug closure fits into a “well” of a seamed-on ring. The plug is pressed into the ring and the two surfaces (the outside and inside edge) come into contact with the ring, creating multiple sealing surfaces on the plug/ring combination

Slip cover:

Cover/closure style in which the cover’s skirt (vertical surface) slips over and to the outside of the can body  

Single friction:

A plug-style metal cap fits snugly into a seamed on ring. The outside edge of the plug presses against the interior edge of the ring, creating one sealing surface

White Coat:

Entire surface of the metal is coated with white before applying other printing ink colors