Single, Double, Triple Bevel Industrial Blades: What You Need To Know
About grinding, angles, bevels / facets and knife sharpness
A vast array of knife kinds and shapes is utilized in the manufacturing of goods and materials, as well as in converting, processing, and other finishing techniques. The diversity of cutting and processing techniques of web materials results in industrial knives of various forms and edge configurations. This article will address essential information on a key aspect of machine knives - sharpening / grinding, often known as the bevel or facet of the cutting edge, along with their varieties and characteristics.
Content:
- What is a knife bevel
- Single bevel / 1 facet
- Double bevel / 2 facets
- Triple bevel / 3 facets
- Bevel vs Sharpness
- Coating
- How to choose the right grinding
The Basics on Industrial Knife Grinding & Sharpening
The quantity of sharp ground knife edges, the sides subjected to grinding, and the varieties of bevel / facets are key parameters that determine the quality and cutting performance of an industrial machine knife, be it a huge guillotine paper knife or a tiny industrial razor blade utilized for converting thin stretch plastic film.
What Is a Knife Bevel?
What is the definition of an industrial knife bevel? The bevel of an industrial knife refers to one or more grinding angles on the blade's cutting edge, which determines the sharpness of the machine knife. Looking closer on the knife cutting edge will reveal a slight grinding angle incline that runs down to the knife edge. This is the bevel. Bevels are also referred to as facets. Using multiple grindings with different angles we create different bevels.
The grinding angle is referred to as a single bevel if it is one, double bevel if it is two, triple bevel if it is three, etc. Single and double bevel grinding are the most common options for industrial knives.
Single Bevel
A single bevel edge-ground industrial blade has only one angle ground on the cutting edge. This angle is usually sharpened to a specific angle, for example 30°, 45°, 60°, depending on the material to be cut, the shape of the blade and the cutting method.
The single bevel is most commonly found on long cross-cutting knives, machine knives for hard materials, plastic pelletizing and granulating, and circular knives. In the picture below are illustrated different machine knives with single bevel angle sharpening.
Because the single bevel industrial blade is narrow at the tip, the knife tip dulls quickly. Furthermore, the tip experiences chipping and damage due to significant wear and tension concentrated at the tip. The most common solution to edge brittleness is to round the tip of the edge, such as is done for score and crush cut circular knives. However, blades with single blade facets are less expensive to resharpen and manufacture.
Double Bevel
Two angles on the cutting edge define a double bevel blade. The slitting knife type and technique affect the angle degrees. Double bevel blades are sharp, robust and durable.
Machine knives and slitting knives with 2 facets on the cutting edge are the most versatile and are used for converting and processing flexible materials.
Triple Bevel
Industrial triple-beveled blades are the sharpest of the above-mentioned blades. The more grinding angles - the sharper your knife is. Therefore, machine knives and industrial triple-edge blades are especially great for difficult-to-cut materials such as stretchy plastic film (if the blade has less sharpening, the film will be torn rather than cut), silicone or latex material (read more in the article “Blades to Cut Latex, Silicone, TPE, ETFE, PTFE [Customer Case]”), aluminum foil and film, etc., and other materials.
However, it's important to keep in mind that triple-beveled blades have a particularly brittle primary grinding bevel, which is just what provides the sharpness for industrial blades.
Bevels vs Industrial Knife Sharpness
The more bevels on the knife's cutting edge, the sharper the knife, but it is also more fragile and has less wear resistance. Therefore, it is important to find a balance and choose the right sharpening for industrial razor blades and machine knives, taking into account the material to be cut, the load on the knife and cutting edge, the type of cutting and other factors.
Generally speaking, a two-bevel or two-facet blade provides both longevity and sharpness. Intricate cuts are produced by three bevels of facet grinding. One discovery about bevels is that the blade is tougher when there are fewer facets. Finer cuts are produced by having more facets.
TIP! The greatest cutting results come from burr-free edges and multifaceted grinding because they provide cleaner edge cuts and fewer blade edge chips and deformations.
Why Industrial Blades Are Coated with an Extra Coating
In short - blade coating prolongs and improves the qualities of industrial blades.
All Sollex industrial razor blades are triple ground ( slotted slitter blades, 3-hole razor blades, injector blades etc) , which guarantees sharpness and the best possible material cuts. Furthermore, polishing and additional coatings on the cutting edge and primary sharpening angle prolong the endurance of the blades and improve their cutting performance. Coatings with materials such as Ceramic or Zero-Friction mean that industrial cutting will wear out the coating on the cutting edge first, while the steel material of the blade and the sharpening will retain its properties longer.
Read more about Sollex best-selling ceramic coated slotted slitter razor blade 5K here.
Cutting Edge Types
Grinding can be done on one or both sides of a machine knife. This means how many sides of the knife blade are ground and have angled bevel. If the knife is single-sided, the second side is flat; if it is double-sided, both sides are beveled. 90% of all knives are ground on both sides. This ensures an easy and smooth cut.
An important feature of often square and rectangular industrial knives is the number of sharp cutting edges, which can be single-edged, double-edged, triple-edged, and so on.
Example of single-edged industrial blade: Sollex P905 toothed / serrated tape knife 65x33x1.2mm D2
Example of double-edged industrial blade: Sollex 5-020-Z Slitter blade 0.20mm Zero Friction
Example of triple-edged industrial blade: Sollex 752.42 trapezoid blade 52mm with 3 cutting edges
One-Sided Machine Knife Types
One-sided industrial knives are grounded so that only one side has a cutting edge, leaving the other side flat. In general, a one-sided slitter knife is a good choice when you need to make a clean cut in soft materials.
Examples of one-sided machine knives used in industrial production:
- top dished-shaped / disc circular slitting knives for cutting a wide range of materials, used in conjunction with a bottom knife;
- pelletizing knives for the production of plastic pellets in a pelletizer, e.g. from Erema;
- guillotine knives also known as cut-off knives, roll splitters;
- granulator blades used to shred plastic into smaller pieces for recycling;
- circular slitting machine knives for cutting plastic film, rubber, cardboard, textile.
One-sided industrial knives can also have one single cutting edge or two cutting edges and therefore there are following types of knives:
- one sided single edged single bevel ( Ex: P808 )
- one sided single edged double bevel
- one sided single edged triple angle bevel and
- one sided double edged single bevel
- one sided double edged double bevel
- one sided double edged triple angle bevel
"Single sided" industrial slitting knives and blades are really only used in three situations:
- When you have a bottom knife or a resistance on the other side of the blade.
- When you can hold the material from one side and "scrape" it as you cut.
- When you want to cut soft materials and have space for the removed material
Read more about single-sided machine knife applications and specifications here.
How to Choose the Right Grinding Angle for an Industrial Knife
The basic rule is as follows: the sharper the blade is required - the more facet angles are needed. A robust knife is required - choose 1 or 2 bevel angles; a sharp knife is required for cutting hard-to-cut flexible materials - buy blades coated with ceramic, titanium or other modern coatings. Also, blades with a well-polished cutting edge will give you better results, so check with your supplier.
Selecting the right blade for industrial cutting is all about finding a balance in the number of grinding bevels, grinding angles, blade material, and cutting edge coating. At Sollex, if you are in doubt about which blades are best for your industrial cutting needs, we can help you find the best machine knives and blades for your material. With our extensive knowledge and experience in the knife industry, we will provide you with the right information and guide you to the perfect solution for your specific requirements.
For over 97 years, Sollex has been manufacturing and providing cutting tools in Sweden and internationally, successfully helping clients overcome different cutting challenges by selecting right knives and blades. Sollex industrial razor blades and machine knives have quality grinding, fine bevel angles, burr-free cutting edge of the blade and proper polishing, which will guarantee the best cutting result for your use.
We suppy the widest range of premium slitting knives in the form of coated slotted razor blades, razor blades with 3 holes, injector blades, crush-cut knives, perforating knives, top and bottom shear slitting knives, but can also manufacture converting circular knives for your slitter machine.
Email us at order@sollex.se with detailed information about which machine knife or industrial razor blade you need, and we will give you the best offer.
