Hyd-Mech V-18, Руководство по эксплуатации и техническому обслуживанию

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Pg 2.9
V18
STEP 4, DETERMINE OPTIMUM BLADE SPEED, V (ft/min) (m/min)
The relationship between optimum
blade speed and effective material
width for various materials is
represented on the graph shown.
The graph shows that as effective
material width gets wider or as material
gets harder, lower blade speeds are
recommended. If material is narrow or
soft, higher blades speeds should be
selected.
In Example #1
- 8" (200mm) diameter #1045 Medium Carbon Steel solid bar is to be cut.
- On the graph above find the Medium Carbon Steel Curve which represents the optimum blade speeds for
1045 Carbon Steel.
- On the horizontal axis (effective material width axis) find number 8 which represents effective material width of
an 8" (200mm) diameter solid.
- Find the point where a vertical line from 8" (200mm) intersects the Medium Carbon Steel Curve.
- From this intersection point run horizontally left to the vertical axis (optimum blade speed axis) and find the
point marked “200”.
For 8" (200mm) diameter, 1045 Carbon Steel solid bar 200 ft/min (60m/min) is the optimum blade speed.
NOTE:
1) Higher than optimum blade speed will cause rapid blade dulling. Lower than optimum blade
speeds reduce cutting rates proportionately and do not result in significantly longer blade life except where there is
a vibration problem. If the blade vibrates appreciably at optimum speed as most often occurs with structurals and
bundles, a lower blade speed may reduce vibration and prevent premature blade failure.
2) Material Hardness - The graph above illustrates blade speed curves for materials of hardness 20
RC (225 Bhn) or lower. If the material is hardened then the multipliers need to be used. These multipliers are given in
the NOTE at the bottom right of the graph. As the hardness increases the optimum blade speed decreases.
STEP 3, DETERMINE OPTIMUM BLADE PITCH - TEETH PER INCH (T.P.I.)
Selecting a blade with proper tooth pitch is important in order to achieve
optimal cutting rates and good blade life.
For cutting narrow or thin wall structural materials a fine blade with many
teeth per inch (T.P.I.) is recommended. For wide materials a blade with a coarse
pitch should be used. The sketch can be referenced for the blade pitch changes
for differing effective material widths.
It is impractical to change the blade to the proper pitch every time a
different width of material is cut and it is not necessary, but remember that the
optimum blade will cut most efficiently. Too fine a blade must be fed slower on
wide material because the small gullets between the teeth will get packed with
chips before they get across and out of the cut. Too coarse a blade must be fed
slower because it has fewer teeth cutting and there is a limit to the depth of a
cut taken by each tooth. Allowance for the use of a non-optimum blade is made
in STEP 5.
In our Example #1 : Effective material width of 8" (200 mm) & Optimum blade has 2/3 teeth per inch.
Optimum Blade Pitch ( T.P.I. )
Optimum Blade Speed Curves