Band Saws STRONGLY REDUCE PRODUCTION TIMEThe speed and quality of sawing is becoming increasingly important. The time when only the purchase price of a band saw counted is therefore over. Large end-users are increasingly opting for more expensive carbide bandsaw blades that significantly increase productivity. In this article, we will discuss the evolution of demand, from bimetal to metal carbide. We will also dwell on the requirements and will inform you of some new developments in this market.
By Philip Viane
Interest in carbide bandsaw blades is still increasing. At this stage, they are gradually a recognized and accepted tool in the metalworking industry. A trend closely linked to the desire for ever faster and more economical production. The output per unit time must be optimal. This also applies to a band saw. Here, carbide blades are a valuable aid.
Change from bimetal to metal carbide
One of the main evolutions among carbide bandsaw blades is the application of a coating. Little by little, large end users move to carbide blades. best bandsaw for money There is a clear evolution in demand.
Companies are increasingly investing in higher quality machines and also want their staff to undergo the corresponding training. The surface of a cut made with a carbide blade is often better than the same cut made with a bimetal blade. The machines suitable for blades of this type are much more expensive and the bands themselves are also more expensive than ordinary bimetal blades. At the moment, this data is still dissuasive for the more modest users.
Requirements for the use of carbide blades
Double Column Band Saw
A carbide band saw blade can not withstand shocks or vibrations if the blade is not set. This is why the carbide band saw blades are often used with a dual-column band saw. An advanced metal carbide blade also gives excellent results on an articulated machine. When sawing with carbide band saw blades, the motor plays a major role. The band saw must have a motor capable of reaching higher speeds because with such blades sawing is carried out at much higher speeds.
Even if the saw is three times more expensive, the share of the saw in the sawing costs is in principle only 2%
Driven chip brush
A driven chip brush is absolutely essential.
This is the only way for larger chips resulting from sawing at higher speeds to be properly removed from the hollow of the tooth. The brush is available in both steel and resistant nylon. On automatic machines, the sawn part as well as the material to be machined should ideally be removed after cutting. This allows the blade to reassemble easily without risking stuck behind the workpiece.
EVOLUTIONS IN THIS MARKET
The effect of a coating is evident if one looks at the cutting forces of an uncoated blade and a coated blade. One of the major evolutions in this market is the coating of the band saw blade. The application of such wear resistant coating involves a number of conditions. Here the precision of the edge is the main requirement to obtain a correct coating, for good sawing performance but also for a longer life of the tooth.
Properties: A coating does not only have a high hardness and good adhesion, greatly reducing tooth wear. The coating on the edge of the back of the blade also contributes to the reduction of friction between the blade and its guide. This prevents the appearance of small cracks in the back of the blade but also guarantees a longer life of the blade. Tests show that the life of a blade with a coating is 1.9 to 2.3 times longer - with cutting parameters equivalent to or even higher than the lifetime of a blade without coating.
Cost: The higher cost of a carbide blade is more than offset by lower production costs per square meter. The higher cutting values of the coated blades can prove valuable to the customer as a backup solution in the event of capacity problems, as there is no need to invest in a new machine.
To use carbide bandsaw blades, a double-column machine should not be used specifically. A blade can be used more universally if it is set. The main advantage of a toothed carbide tooth is its 'clemency'. The abutting teeth dampen all necessary shocks. This makes it possible to saw non-alloy materials, and even tubes and profiles. It is known from experience that a non-alloyed material can be sawn up to 2-3 times faster with a carbide band saw blade than with a bimetallic model. Tool holding is also multiplied by two. Today, one finds even blades of metallic carbide laid out not cutting a chip in 3 but in 7 pieces. The main advantage is that the removal of material per tooth is smaller. The advance can therefore be increased and the material is sawn twice as fast as with a normal carbide band saw blade. Thanks to these evolutions, the machining speed is multiplied by five compared to a bimetallic blade. Some blades involve a minimum power of 3.5 kW; Other producers target 8 kW. best vertical band saws Higher power is better, but stainless steel can, for example, Already sawn with a smaller power.
Sawing principle for self-hardening materials
For self-hardening materials, some manufacturers have developed a specific sawing principle. In the context of this principle, a corrugation is formed in the back of the band with a large abrasive band. During sawing, the blade thus passes by undulating by the guides, in a movement comparable to the movement of the sawing with a hand saw. This makes it possible to saw each time under the self-hardening layer. This method ensures more efficient penetration and chip formation and is suitable for both carbide and bimetal blades. The same concept exists with an undulating movement in the teeth and not in the back.
With carbide blades, a machine must run much less
A blade is needed to secure the band path. The way is paramount for each machining by removal of material. Without track, the tool gets stuck in the room. Too large a track gives a rough surface when sawing, especially the band saw. This can be achieved by spreading the teeth, or by welding a large carbide insert at the incision and finishing tooth and then grinding it to form it. The advantage is that all the teeth are positioned one behind the other with more precision. However, the teeth are more sensitive to vibrations.
The stainless steel is sawed with a bimetallic blade at a speed of 35 m / min, because the heat generated during the sawing must be evacuated.
With a carbide band saw blade, speeds ranging from 80 m / min to 110 m / min are achieved.
There are carbide bandsaw blades that do not require a primer. Today, each provider has a different priming method, which causes some confusion among operators. As a result, the blades are poorly primed. Especially in the case of metal carbide blades, this has a negative impact on tool holding and productivity. Thanks to special machining in the production process, the operator can skip this step taking time and produce directly at full power. It does not lose time at the beginning and the risk of errors during the primer is reduced to 0.