Circular Knives and Round Knives

What Is a Circular Knife?
Circular knives, also known as circular blades or round knives, are rotating cutting tools used in industrial cutting and slitting systems. Their round or disc-shaped design allows them to perform continuous cutting operations at high production speeds.
Depending on the cutting system, circular knives can operate using different cutting principles. Two common principles are crush cutting and shear cutting.
In crush cutting, the circular knife presses the material against a hardened counter surface or anvil. The material is cut or separated by the pressure between the rotating knife and the counter surface.
In shear cutting, the circular knife works against a matching counter knife. The two cutting edges pass each other with a precisely defined clearance, similar to the cutting action of scissors.
Circular Knives for Industrial Applications
Circular knives are used in a wide range of industrial applications, including:

Paper and cardboard processing Packaging and converting Plastic and film processing Textile and nonwoven processing Food processing Rubber processing Recycling Metal processing

Depending on the material and cutting process, circular knives can be designed with a smooth, serrated or toothed cutting edge.
Circular Knives and Round Knives – Custom Designs
Circular knives can be manufactured in different diameters, thicknesses and cutting geometries. The design can be adapted to the specific machine and application.
Possible features include:

Single- or double-sided grinding Different cutting angles Serrated or toothed edges Special edge geometries Corner radii Customized bore diameters Mounting holes Special tolerances

The appropriate geometry depends on the material being cut, cutting principle, machine configuration and required cutting performance.
Materials for Circular Knives
We manufacture circular knives and round knives from a range of suitable materials, depending on the application.
Possible materials include:
Carbon steel
Chrome steel
Tool steel
High-speed steel (HSS)
HSS PM
Stainless steel
Carbide
The material is selected according to the material being processed, cutting speed, operating conditions, required hardness, wear resistance and desired service life.
Circular Knives for Slitting Systems
Circular knives are widely used in slitting systems for continuous web materials. Several knives can be mounted on a knife shaft using knife holders, spacers and intermediate rings.
This configuration allows multiple longitudinal cuts to be made at precisely defined positions.
Typical materials include:
Paper
Cardboard
Film and foil
Plastic
Packaging materials
Textiles and nonwovens
The correct combination of circular knife, knife holder, shaft and counter knife is important for achieving consistent cutting quality.
Circular Knives for Shear Cutting
In shear cutting systems, circular knives work together with a matching counter knife. The upper and lower knives are positioned with a controlled cutting gap.
The geometry of both knives must be matched to the material and machine to achieve a clean cut, low cutting forces and long service life.
Circular Knives for Crush Cutting
Crush cutting systems use a rotating circular knife together with a counter surface or anvil. This cutting principle is commonly used for flexible web materials and other industrial applications.
The knife geometry, material, cutting pressure and anvil condition all influence the cutting result and knife life.

Custom Circular Knives
We manufacture custom circular knives and round knives according to customer drawings, specifications or samples.

Depending on the application, we can manufacture individual:

• Diameters
• Knife thicknesses
• Bore diameters
• Cutting angles
• Edge geometries
• Serrated or toothed edges
• Mounting holes
• Tolerances

This allows the circular knife to be precisely matched to the machine and cutting process.
Grinding and Resharpening of Circular Knives
Precision grinding is essential for achieving the required cutting-edge geometry and dimensional accuracy.
Depending on the knife design and remaining dimensions, many circular knives can be reground and resharpened several times. Professional regrinding can extend knife life, maintain consistent cutting performance and reduce replacement costs.
The actual number of possible regrinds and the achievable cost savings depend on the knife dimensions, material, cutting geometry and application.
If you require circular knives, round knives, rotary knives or custom circular blades, send us your drawing, sample or technical specifications. We manufacture precision circular cutting tools for a wide range of industrial applications.