Guillotine knives for metal cutting
Sheet metal cutting on guillotine machines is based on the principle of shear fracture of the material. The workpiece is fixed with a clamp, after which the upper knife moves towards the stationary lower one. A concentrated stress is created between the cutting edges, at which the metal is first plastically deformed and then destroyed along the cutting line. The quality of this operation directly depends on the geometry, hardness and condition of the cutting tool. That is why a guillotine knife for metal is considered not as a consumable part, but as a key element of the entire cutting system.
The characteristics of the blade depend not only on the purity of the blade, but also on the load on the machine, the wear of the guides, the stability of the gap between the blades and the repeatability of the workpiece dimensions.
Types of guillotine knives
The design of the knives and the materials used vary depending on the type of equipment, the metal being processed, and the operating mode of the production.
Straight knives for sheet guillotines
This is the most common type of tool. The blade has a straight geometry and is mounted on mechanical, hydraulic or pneumatic guillotines.
Features of such blades:
- uniform RC along the entire length;
- high rigidity for working with wide sheets;
- the possibility of multiple overflows.
They are usually made of tool steels with increased wear resistance. This is necessary because during cutting, the metal creates significant contact loads and an abrasive effect on the edge.
Stainless Steel Cutting Knives
Stainless alloys are characterized by high viscosity and a tendency to riveting. When cutting, the load on the RC increases, so standard knives made of universal steels quickly lose their sharpness.
For such conditions, the following apply:
- alloyed tool steels;
- increased hardness of the cutting area;
- stricter requirements for edge microgeometry.
This reduces the burrs on the edge and reduces the risk of micro-chips.
Knives for high-strength and thick-sheet metals
When working with high—thickness structural steels, the main problem is not only wear, but also the risk of blade deformation.
Therefore, such models differ:
- increased cross-section;
- increased core strength;
- resistant to shock loads.
In some cases, steels with combined properties are used: high hardness of the cutting edge and a more viscous base structure.
Tips for choosing
When choosing knives for the guillotine, it is not enough to consider only the size and price. An incorrectly selected tool accelerates wear