The productivity of the band saw is directly dependent on how well the band saw blade is selected. Share our tips.
The productivity of the band saw is directly dependent on how well the band saw blade is selected. There are many varieties of saw tapes that differ:
- material of manufacture;
- tooth shape;
- their sharpening;
- type of wiring.
The band saw blade for metal is made of carbon steel with a monolithic structure or a bimetallic composition. Steel sheets with tensile strength up to 80 MPa are designed for sawing non-ferrous metal, plastic, solid steel and cast iron billets. They have proven themselves on cantilever and single-column machines for industrial and semi-industrial purposes.
On powerful two-rack machines, in most cases, a tape bimetallic sheet for metal is used. This type of saw has a complex structure, the basis of which is a flexible and durable spring steel tape, on which teeth made of tool steel 1R2M10K8 high-speed grade (or other alloys with similar characteristics) are soldered. They are characterized by high hardness, about 950 HB. The teeth are located in special sockets and fixed by electron beam soldering.
Bimetallic band saws are used for cutting cast iron, steels of all kinds, especially strong alloys. As a rule, they are used for working with continuous workpieces; it is better to use ordinary steel saws when cutting pipes and profiles.
If you choose the shape of the tooth and the wiring correctly, then carbide tape blades do an excellent job with all types of stainless steel.
Types of bandsaw teeth
The band saw blade is equipped with teeth in an amount of 1 to 32 per linear inch. If the choice of tape blade requires an inconsistent tooth pitch, then their number is in the range from 0.75 / 1.25 to 10/14 per inch. The number of teeth depends on the density of the teeth, which resides in the cutting zone at the same time. Optimum. 3-5.
The teeth of the cutting edge are not located in a straight line, but are deflected to the sides of the plane of the main tape. The kind of deviation is called the saw layout. The teeth are alternately inclined to the right and left side, which ensures a wider cut line than the thickness of the blade, and eliminates its jamming in the material. Three types of wiring are most commonly used:
Video: Choosing a Band Saw Blade
- right, straight tooth and left;
- right and left alternately;
- wave wiring with a variable angle of inclination of the tooth.
The first type is used when cutting packages of continuous billets, pipes, profile rolled products. Wavy. for pipes, especially thin-walled, rolled small sizes with a small wall thickness. The standard right / left is almost universal, but it works best when cutting soft materials. copper, aluminum, non-ferrous alloys and plastic.
- NORMAL Tooth (N) It does not have a slope in front. The working edge is directed vertically upwards. It is used for cutting high-carbon materials, thin-walled pipes and rolled products.
- HOOK (H) has a slope of the front of 10 0. Its purpose is cutting pipes with a thick wall and a solid rod of any section made of alloy steel.
- For non-ferrous alloys, high alloy steels, and hard-to-handle metals, a band saw blade equipped with Tooth RP with a slope of the working edge and at 16 0.
- Tooth-shaped tape MASTER It is highly versatile, except for the working frontal edge with an angle of 10 or 16 0, a longitudinal chamfer is ground, as a result of which the roughness of the cut is significantly reduced. Such saw tapes are used on all types of machine tools for metal.
The thickness of the material that it can process depends on the step of the saw. When cutting solid metal, a blade for a band saw with one step is selected, pipes with another. Sample parameters are given in the tables below.
- thin or dusty — feed is too slow or the linear speed of the belt is too high;
- large chips, with a bluish-blue tint. high feed rate or linear speed is low;
- twisted spiral, the same length chip. the correct operation mode.
Each band saw blade is characterized by a specific productivity and the ability to perform a certain number of cuts. For example, bimetallic 27×0.9 is characterized by productivity of 10-25 cm / min when cutting high alloy alloys and 45-70 cm / min when working with steels of structural grades. The average operating time of the band saw blade is 150-170 hours of operation.
Band Saw Care
To extend the life of the tape during breaks in work, it should be removed from the machine and stored in an unstressed condition. On the machine, the web tension should not exceed 300 n / m; exceeding this indicator threatens with a metal break or deformations.
During operation, the coolant supply must be observed. Without lubrication and cooling, the life of the tape is significantly reduced. When installing a new blade, you should “roll” it in idle mode for 10-15 minutes and only then perform several sawings in the mode with a load of up to 50% of the nominal.
The correct operation and durability of the band saw depends on the sharpening and wiring. For these operations, special machines with various setting modes are intended. When sharpening, in addition to actually restoring the sharpness of the teeth, microcracks and defects that occur in the sinuses are eliminated. Adjusting the height of stock removal is also very important to maintain the strength of the blade.
Sharpening is performed without pressing the grinding wheel, in order to avoid annealing of the tape, which can occur even with the correct settings for the type of tooth and its pitch.