Hyd-Mech DM-1215, Руководство по эксплуатации и обслуживанию

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9 − 3 111 Cutting speed and choice of tools
Choice of blade
When using band saws to cut metals, an important factor is the choice of pitch,
i.e. the number of teeth per inch (25.4 mm.), which must be suitable for the
workpiece material. The following recommendations may be taken as general
guidelines:
thin-walled materials, such as sheet steel, tubes and profiles require a fine
pitch frequency 3 to 6 teeth should be engaged in the breadth of the material
at any one time;
large section cutting requires a coarse pitch to cope with the higher volume of
swarf and optimal tooth penetration;
soft materials (aluminium alloys, soft bronze etc.) also require a coarse tooth
pitch.
Saw tooth pitch
The choice of teeth per inch, therefore, depends on various factors:
the size of the section;
the hardness of the material;
workpiece wall breadth.
Very large dimensions require coarse teeth, while small dimensions require finer
teeth. Whatever the case, ensure that there are always at least six teeth engaged
in the cut, with reference to the thinnest vertical walls positioned transversally to
the blade.
Concerning the type of Shark machine, a first broad distinction can be made
according to the hardness of materials:
< 61 HRB > 65 HRB
< 55 kg/mm
2
> 65 kg/mm
2
3 / 4
4 / 6
8 / 12
5 / 8
6 / 10
10 / 14
Mild steels
MINIMUM
OPTIMUM
MAXIMUM
Hard steels
NR. TEETH/INCH NR. TEETH/INCH