How to choose and use metal band saw blades?

Band saws for metal are indispensable units in many blank production industries. In the article we will consider their varieties, main characteristics, dwell on the principle of operation and note the main selection criteria, thanks to which the reader will be able to decide on the purchase of the best option for sawing equipment.

Band saws are classified according to several criteria. These include the parameters of the cut (its height and width), the type of the cutting blade, the power of the electric motor. Sawing equipment for metal differs in different power, cutting speed, size, weight and functionality. Based on this, its cost is also different.

The belts can separate metal workpieces that are strong, hard and resilient. They are more reliable than pendulum disk counterparts and are distinguished by high durability due to the continuous supply of coolant to the processing zone. As for the speed of the belt, it is worth noting: it can be constant or variable. The first options are rare today, the speed of the second varies in the range of 10-100 m / s.

The saw band drive power can be from 2000 to 2500 W and more (depends on stationary or portable type). Some products provide for changing the cutting parameters. According to the GOST regulations, each band saw blade has its own width, base, length, thickness, saw back. In addition, its technical characteristics are the distance between the teeth, the tooth pitch, as well as design features (for example, the geometry of the tooth, its sharpening angle and material).

The design of the band saw is nothing more than a bed with a fixed electric motor and roller mechanism. A band saw is a cutting tool used for band sawing machines. In fact, the steel belt with its inherent flexibility is considered the key organ of the machine. It has teeth that are located along one edge. In other modifications, there are no teeth, here cutting occurs due to the friction of the working surface of the belt against the material being processed or by the method of electric impact. With the help of a metal band, you can make straight and curved cuts.

The canvas itself provides for multiple use in construction. Install the saw band on 2 pulleys (one of which is driving), due to which the electric motor of the band saw machine rotates.

Also, there can be not only 2, but also 4 pulleys. The more there are, the more compact the machine and the longer the cutting blade. The belt has a preset tension, which can be done manually or by means of a hydraulic tensioning system. The presence of hydraulics increases the cost of the machine and also simplifies the work of the operator. In order to check the accuracy of the belt tension, a tensometer is used.

The band saw equipment operates from a single or three-phase network, depending on the type of specific model (industrial or for household use). At the same time, there are fewer opportunities for modifications belonging to the light weight class. During operation, the saw rotates in a circular path. When the drive turns on, the web starts moving. The teeth on the cutter bar begin to cut through the metal.

In this case, the workpiece is fed to the cutting work area at a specific speed. Depending on the type of model, the operator can independently select the optimal belt rotation speed due to an alternating current electric motor with a variator. The type of teeth can be narrow or wide. The height of the tines must match the width of the platform. As a rule, it makes up 20% of the working area, otherwise it simply cannot cope with the imposed load.

Models of vertical band saws are professional and household. Belt-type machines for metal differ from their counterparts for wood by using special blades. Unlike woodworking machines, a lower blade speed is noted here. In addition, this equipment has a higher power motor that can withstand heavy loads. The cutting profile here can be very diverse.

Conventionally, products of this type are divided into 4 classes.

• Class 1 modifications belong to the category of universal. They are more expensive than other analogs, are designed for metals of different density (from aluminum and copper to high-alloy steel), are characterized by significant weight and dimensions. In fact, this is an automated volumetric technique, which is often equipped with a coolant supply and an automatic feed of the workpiece. These are industrial-type units with maximum metal processing efficiency.
• Analogs of the second class somewhat inferior to previous models, since they cannot give a perfect cut-off edge. However, they are also used in production, conventionally referring to universal equipment. These are machines equipped with automation and semi-automatic units in which the workpiece is fed manually. Of the two varieties, automatic is considered the best, since it is they who have more accurate edge processing.

• Third category means equipment for sawing metal with less cutting precision. The line includes automatic, semi-automatic and hand saws. Such machines are used mainly in small workshops, they are characterized by low productivity. They are not suitable for mass production as they have a slower processing speed. Products of this class are less durable and require careful handling.
• Class four modifications are considered household. They are distinguished by functionality and dimensions. The line includes table-type electric cut-off saws. These are portable hand-held devices or so-called mini-saws. They feed the workpiece manually, the functionality is minimal, and therefore the cost of products is noticeably lower than analogues of the first class.

Based on the type of material, band saws are divided into 3 types: options from carbon steel, bimetallic blades with high-speed steel and modifications with a carbide tooth. As for the best option, this is the last type, since it is these saws that cope with especially heavy metals.

Today the market for metal band sawing equipment is rich in a wide variety of proposals. Among the rich list of manufacturers, there are several brands that are popular with buyers.

• Arntz produces carbide models of tape machines. The products of the German manufacturer are distinguished by their reliability, assembly quality and are manufactured under quality control at all stages of production.
• Products of the American brand Lenox differs in the application of a layer of protection made of titanium aluminum nitride to the saws. These models, although expensive, are particularly durable and wear-resistant, they can cut metal with high abrasiveness.

• Forezienne - French brand, engaged in the production of band saws from steel from beneficiated ore. During forming, there is an alternation of quenching and tempering, hot and cold rolling, which makes the company's saws one of the best in their segment.

• Lennartz is a global manufacturerwhich manufactures composite alloy saws. The method of making saws provides for making a blade and hardening from extra strong steel, as well as welding a toothed edge made of high-speed steel.
• Rospil is a Russian manufacturer, which produces bimetallic and carbide band saw blades for metalworking. Blades are made from high speed steel, nickel and titanium alloys, as well as cold and hot rolled structural steel.

Choosing the optimal band saw equipment, they are based on the operating conditions. Also, they take into account the design features of a particular unit, its functionality, purpose, level of automation, technical characteristics. It is worth considering that for using the unit in industrial production it is more expedient to buy an expensive option with a high level of strength and reliability.

When choosing a blade for machine tools, take into account the length and width, while not forgetting to correlate the nuances of the design with the parameters of the cutting device. The best saw is the wide type. It should be noted that when working with particularly dense workpieces, the thin blade deforms quickly. At the same time, if the workpieces to be processed are made of thin metal, it is undesirable to saw them with a thick tape.

If the tape is selected for cutting contoured curly edges, it is important to correlate the width of the cutting element with the possibility of cutting at the desired angle. Considering that the range of tape width ranges from 14-80 mm, it is worth choosing the golden mean (for example, the option with an indicator of 4 cm). As for the choice of teeth, it can be noted: there are more of them, which is especially good for cutting thick metal. If the teeth are sparse, this indicates that this saw has a small load on the blade area.

Paying attention to the dimensions of the teeth, the buyer can note for himself: if they are large, the tape cuts deep enough. For thin metal sheets, a low cutting edge is ideal. When talking about the tooth setting, which has a direct effect on the efficiency of the unit and the level of vibration, it is important to know: for cutting small parts made of thin metal, a wavy profile is sufficient. If the metal is bulky or the machine model is vertical, take a standard profile. Variable is good for having a pair of teeth - this is the most effective option.

It is not allowed to use the saw with maximum load immediately after purchase. Before you start using it in normal mode, you need to set up the unit and run in the equipment. Before that, adjust the working elements, check the operating modes, inspect the saw for visual damage. Running-in will allow the new teeth to be shaped and strengthened.

In addition, this process helps to extend the life of the blade. It is carried out at the saw speed recommended by the manufacturer.The cut is performed at the workpiece feed rate (50% less than usual). After about 20 minutes, you can increase the cutting rate by increasing the feed rate to the recommended cutting rate. To achieve a good cut and sufficient penetration into hard metal, you need to gradually increase the feed force (accelerate the pace).

Band saws for metal are used in home production, on sawmills, band saws and split saws. This equipment is used for cutting metal along a complex contour that does not need a clear edge cleanliness, because in the future the joints will be welded into a specific structure. For example, you can cut metal in the shape of an ellipse, a parabola.

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