Band saws for metal are indispensable units of many procurement industries. In the article we will consider their varieties, basic characteristics, dwell on the principle of work and note the main selection criteria, thanks to which the reader will be able to decide on the purchase of the best version of the sawing equipment.
Classify band saws on several grounds. These include the parameters of the cut (its height and width), the type of cutting blade, the power of the electric motor. Sawing equipment for metal is characterized by different power, cutting speed, size, weight and functionality. Based on this, its cost is different.
Tapes can separate workpieces of metal, characterized by strength, hardness and elasticity. They are more reliable than pendulum disk counterparts and are characterized by high durability due to the continuous supply of coolant to the processing zone. As for the speed of the tape, 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 machines are characterized by different blade tension, high motor ability and sufficient capacity of the hydraulic reservoir. Based on the modification, they can be equipped with options for changing the cutting parameters, compact size, the ability to configure and adjust the machine for cutting metals of different hardness. The type of metal feed depends on the type of band saw.
The power of the band saw drive can be from 2000 to 2500 W or more (depending on the stationary or portable type). Some products include changing cutting parameters. According to the GOST regulations, each tape blade has its own width, base, length, thickness, and back of the saw. In addition, its technical characteristics are the distance between the teeth, the tooth pitch, as well as structural features (for example, the geometry of the tooth, its sharpening angle and material).
Device and principle of operation
The design of the band saw is nothing more than a bed with a fixed electric motor and a roller mechanism. A band saw is a cutting tool used for band saws. In fact, the key organ of the machine is steel tape with its inherent flexibility. It has teeth that are located on one edge. In other modifications there are no teeth; here, cutting occurs due to friction of the working surface of the tape on the material being processed or by the method of electrical exposure. With the help of a metal tape, it is possible to make cuts of a straight-line and figured type.
The canvas itself provides for repeated use in construction. Set the saw blade on 2 pulleys (one of which is driven), due to which the rotation of the electric motor of the band saw.
Also, there can be not only 2, but also 4. There are more pulleys, the more compact the machine and the longer the cutting blade. The tape has a predetermined tension, which is 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 tension of the tape resort to a tensometer.
Band saw equipment operates from a single or three-phase network, which depends on the type of specific model (industrial or residential). At the same time, there are fewer options for modifications related to the light weight class. In the process, the saw rotates in a circular path. When the drive is turned on, web movement starts. The teeth located on the cutting mechanism begin to cut metal.
In this case, the workpiece is fed to the working area of the cut with a specific speed. Depending on the type of model, the operator can independently choose the optimal speed of rotation of the tape due to an alternating current motor with a variator. The type of teeth can be narrow and wide. The height of the teeth should be subject to the width of the platform. As a rule, it makes up 20% of the work area, otherwise it simply will not cope with the assigned burden.
In the process of cutting, you must take into account the correctness of the interval between the tape and the work area itself. In order to avoid jamming, a tooth bite is performed before work. The first of them is located at an angle to the left, the second - to the right, the third - directly. This order is repeated. It turns out that two teeth saw through the metal, and the third helps to clean the sawdust.
Models of vertical band saws are professional and domestic. Band-type machines for metal differ from their wood counterparts using special canvases. Unlike woodworking machines, a lower web speed is noted here. In addition, this equipment has a motor with a higher power that can withstand heavy loads. The cut profile here can be the most diverse.
Conventionally, products of this type are divided into 4 classes.
- Modifications of the 1st class are classified as universal. They are more expensive than other analogues, are designed for metals of different densities (from aluminum and copper to high alloy steel), are characterized by significant weight and dimensions. In fact, this is a volumetric technique of an automated type, which is often equipped with a coolant supply and automatic processing of the workpiece. These are industrial type aggregates with maximum metal processing efficiency.
- Analogs of the second class are somewhat inferior to previous models, because they can not give an ideal cutting edge. However, they are also used in production, conditionally 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 ones are considered the best, since it is they who have more accurate edge processing.
- The third category means equipment for sawing metal with less accuracy. 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 lower processing speed. Products of this class are less durable and require careful handling.
- Modifications of the fourth class are considered household. They are distinguished by functionality and dimensions. The line-up includes table-type electric cutting saws. These are portable portable devices or so-called mini-saws. Their workpiece supply is manual, the functionality is minimal, and therefore the cost of products is noticeably lower than the first-class analogues.
Based on the type of material, band saws are divided into 3 types: carbon steel options, bimetallic blades having high-speed steel and carbide tooth modifications. As for the best option, this is the last type, since it is precisely such saws that cope with especially heavy metals.
They can cut solid elements with a diameter of more than 6 cm. Bimetallic analogs give way to them, but they are better than the first products that are widely used for economical cutting of various steel grades.
Overview of popular brands
Today the metal band saw equipment market is rich in a wide variety of offers. Among the rich list of manufacturers, there are several brands that are popular with buyers.
- Arntz company produces carbide models of tape machines. German products are reliable, build quality and are made under quality control at all stages of production.
- The products of the American brand Lenox are distinguished by applying a protective layer made of titanium aluminum nitride to the saws. Although these models are expensive, they are particularly durable and durable, they can cut metal with high abrasive.
- Forezienne is a French brand engaged in the production of band saws from steel from enriched ore. During molding, there is an alternation of hardening and tempering, hot and cold rolling, which makes the company’s saws one of the best in its segment.
- Lennartz is a global manufacturer of composite alloy saws. The technique for manufacturing saws involves the implementation of the blade and hardening of particularly strong steel, as well as welding of the serrated edges of high-speed steel.
- Rospil is a Russian manufacturer of bimetallic and carbide band saw blades for metalworking. Cloths are made of high speed steel, nickel and titanium alloys, as well as cold and hot rolled structural steel.
Subtleties of choice
Choosing the optimal band saw equipment, they are repelled from operating conditions. Also, this takes into account the design features of a particular unit, its functionality, purpose, level of automation, technical specifications. It is worth considering that for using the unit in an industrial environment it is more advisable to buy an expensive option with a high level of strength and reliability.
When choosing a blade for machines, consider the length and width, not forgetting to correlate the nuances of the design with the parameters of the cutting device. The best saw would be a broad type option. It is worth noting that in working with particularly dense workpieces, a thin blade quickly deforms. 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 right angle. Given that the range of tape width ranges from 14-80 mm, it is worth choosing a middle ground (for example, a variant 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 rare, this says that this saw has a small load on the surface of the blade.
Paying attention to the size of the teeth, the buyer can note for himself: if they are large, the tape is sawed deep enough. Thin metal sheets ideally require a cutting edge with a low height. Speaking of tooth wiring, having a direct impact on the efficiency of the unit and the level of vibration, it is important to know: for cutting small parts of thin metal, a wavy profile is enough. If the metal is voluminous or the machine model is vertical, they take a standard profile. The variable is good by having a pair of teeth - this is the most effective option.
Recommendations for use
Immediately after the purchase, you cannot work with a saw with maximum load. Before you start using it in normal mode, you need to configure the unit and run-in equipment. Before that, adjust the working elements, check the operating modes, inspect the saw for visual damage. Running in will allow to shape new teeth, it will strengthen them.
In addition, this process extends the life of the web. It is carried out at the saw speed recommended by the manufacturer. The cut is performed at the feed rate of the workpiece (50% less than usual). After about 20 minutes, you can increase the cutting rate, increasing the feed rate to the recommended cutting. In order to achieve a high-quality cut and sufficient penetration into solid metal, it is necessary to gradually increase the feed force (to accelerate the pace).
Sawing after running in needs to maintain the cutting rate. However, it is unacceptable to exceed the tempo limit: this will make the cut oblique, and the blade will quickly become dull. During operation, make sure that the hands and edges of the clothes are not too close to the rotating saw. The canvas is pulled taking into account the particular model, advancing the guide close to the workpiece.
Use band saws for metal in the home, sawmills, band saws and cutting saws. This equipment is used for cutting metal along a complex contour that does not need a clear edge, because in the future, the joints will be welded into a specific structure. For example, you can cut metal in the form of an ellipse, parabola.
In addition, with these tapes, it is possible to perform straight and angular cuts on metal rods, pipes, as well as profile rolled tubular and solid cross sections.
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