Hyd-Mech H-18 ASV, Manual

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2.12 2.13
back up. To set FEED RATE for particular cutting situations use the Graph below, which represents the relationship be-
tween FEED RATE, blade speed and blade pitch.
NO. MATERIALS OPTIMUM BLADE SPEED
ft/min m/min
1 5” (125mm) Dia Solid Carbon Steel 225 70
2 12” (300mm) I-Beam 290 90
3 4” x 4”(100 x 100mm) Rec Tube, 1/4” (6mm) Wall 350 110
4 4”(100) 400 Stainless Steel 140 45
5 2” x 2” (50 x 50mm) Rec Tube 1/4” (6mm) Wall
Bundle 5 x 5 pcs 10” x 10” (500 x 500mm)
325 100
6 3” x 3” (75 x 75mm) Inconel 60 20
For Example #1, it is known from Step 3 that optimum blade pitch is 2/3, and from Step 4 that blade speed is 200 ft/min
(60mm/min). From the Graph on the left, the FEED RATE is determined in the following way:
• On the horizontal axis (blade speed axis), find 200 ft/min (60mm/min).
• Find the point where a vertical line from 200 ft/min (60mm/min) would intersect the 2/3 blade pitch curve.
• From this intersection point run horizontally left to the vertical (FEED RATE) axis, to arrive
at 1.8 in/min (45mm/min) FEED RATE. Thus 1.8 in/min (45mm/min) is the FEED RATE
for cutting 8” (200mm) diameter 1045 Carbon Steel when the optimum 2/3 pitch blade is
used.
Feed Rate, continued
If the saw is fitted with a blade coarser than optimum (e.g.: 1.4/2.5 TPI) we can still use the graph,
but we go to the 1.4/2.5 curve. As a result we find that the FEED RATE is decreased to 1.3 in/min
(133mm/min) for this blade. If however, the machine is fitted with a finer than optimum blade (e.g.
3/4 TPI) we use the graph for the optimum blade as before, and then use a multiplier given by the
table below.
NOTE:
Use the following chart when cutting solids. For structurals, see “CUTTING STRUCTURALS” in STEP 2.
ADDITIONAL CUTTING SETUP EXAMPLES
EXAMPLE # 2
Material:
Round Steel Tube SAE 4320 - Hardened to 35 RC (325
Bhn )
Dimensions - 6” O.D. x 4” I.D. (150mm O.D. x 100mm
I.D.)
Step 1 Effective Material Width:4 1/2” (.75 X 6) 114mm
(19 x 6)
Step 2 Feed Force limit setting for 6” Diameter material
Refer to Feed Force Limit, Setting in Step 2
Step 3 Optimum blade pitch (TPI), 3/4 T. P. I.
Actual blade pitch on the saw: 4/6 T. P. I.
Step 4 Optimum blade speed for 4 1/2” effective 225
ft/min (70m/min) material width (70m/min x .60 =
42m/min)
Blade speed reduced by hardness factor: 225