Cosen SH-710LDM, Инструкция по эксплуатации

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7 ‐ 3
Material Size and Shape:
The optimum material width for a band saw blade is 1 inch wide by 0.35 thick and is about 5 inches
long. Below this width tooth loading may become excessive and the cutting rate must be reduced.
Above this width blade control begins to be lost, as discussed below. Since the blade "sees" only that
material it is cutting, the shape of the stock being cut will also affect cutting speeds, particularly if the
piece is excessively wide or if it varies in the dimensions being cut.
Guide Spacing:
The rigidity of the blade is a function of guide spacing, with rigidity being reduced to the third power
as the distance between the guides increases. For example, with guides spaced 2 inches apart, blade
deflection might be approximately 0.2. Under the same conditions, but with the guides spaced at 4
inches apart, blade deflection would be approximately 0.8.
This is a much simplified version of the formula, because it does not consider band tension or guide
design. It is important to recognize, for example that rollers are considered as a pivotal contact.
Whereas carbide faces could be considered as anchored supports. A more complete deviation,
including band tension and guide design, is included in Roark's handbook, "Formula for stress and
strain".
Blade selection:
There are five types of blade material generally used:

Hard ‐ back carbon

Semi ‐ high speed

High speed

Carbon

Electron ‐ welded blade
In most high speed production cutting either the semi ‐ high speed or the electron ‐ welded band are
used. Electron welded blade is the best blade. But it is also the most expensive. To construct the
electron ‐ welded blade, M ‐ 2 tool steel is welded to the blade back. Therefore the blade is capable of
very high surface speed. The semi ‐ high speed blade is used more in structural because it is capable of
taking a great deal more abuse. The hard ‐ back carbon blade's teeth does not have red ‐ hardness but if
the blade is run slowly it can be very economical. We do not recommend carbon blades because the
back of the blade is not sufficiently strong to stand adequate tension and because it has poor
resistance to heat and abrasion. Usually, the coarse hook tooth blade will give better results, but
accurate feed control is a must with a coarse tooth blade.
Flexible
Back
Weld
Fig. 7.3 Electron Welded Blade