Difficulties in hard turning gears after heat treatment
(1) After the heat treatment, the hardness reaches HRC58-62, and the tool wears quickly, which affects the production efficiency;
(2) Some gears have intermittent cutting conditions (the inner hole has a keyway or a group of holes on the end face), and the
tool is easy to collapse during the machining process, and the production cost is high.
(3) After heat treatment of large gears, not only the hardness is high, but also the deformation amount is large, which has high
requirements on the wear resistance and impact toughness of the cutting tool.
In view of the above difficulties in hard turning gears, Halnn has professional CBN tools recommendations to ensure excellent wear
resistance, strong impact toughness and fracture resistance, and high precision and high quality gears.
The specific tool solutions are as follows:
1, Continuous cutting
Process: After the heat hard turning gears. Recommended BN-H10 grade and BN-H11 grade CBN tools. The advantage is that
high-speed cutting can be achieved, which is N times longer than ceramic blades.
Continuous cutting gear comparison result
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Processing: Finishing
Gear hardness: HRC58-62
Tool type: BN-H11CNGA120408
Parameters: Cutting speed (Vc)=180m/min,
Feed rate(Fr)=0.1mm/r,
Cutting depth(ap)=0.2mm
Processing method: dry cutting
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Tool material
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Cutting speed (Vc) m/min
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Tool life pcs/edge
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Production beat pcs/s
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Halnn BN-H11
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180
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800
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6
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a brand of ceramic blades
|
130 |
150 |
8.5 |
2,Semi-interrupt cutting
Process: After the heat hard turning the inner hole of gears (dry cutting). Recommended composite CBN tool BN-H21 grade. The
advantage is that it can withstand the impact of the keyway during hard turning.
Semi-interrupt cutting gear comparison result
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Processing: Finishing
Gear hardness: HRC58-62
Tool type: BN-H21WNGA120408
Parameters: Cutting speed (Vc)=120m/min,
Feed rate(Fr)=0.1mm/r,
Cutting depth(ap)=0.25mm
Processing method: dry cutting
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Tool material
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Cutting speed (Vc) m/min
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Tool life pcs/edge
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Tool cost
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Halnn BN-H21
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120
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700
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Save 50%
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A European brand CBN tools
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120 |
650 |
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3,Heavy interrupt cutting
Process: After the heat hard turning gear end face (group hole - interrupt cutting), it is recommended to use BN-H21 grade composite
CBN tool. The advantages are: high cost performance, stable cutting performance, and the advantage of replacing imported tools.
Heavy interrupt cutting gear comparison result
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Processing: Finishing
Gear hardness: HRC58-62
Tool type: BN-H21WNGA080408
Parameters: Cutting speed (Vc)=300m/min,
Feed rate(Fr)=0.1mm/r,
Cutting depth(ap)=0.3mm
Processing method: dry cutting
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Tool material
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Cutting speed (Vc) m/min
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Cutting depth
mm
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Tool life
pcs/edge
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Halnn BN-H21
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300
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0.3
|
600
|
A European brand CBN tools
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300 |
0.3 |
450 |
4,Heavy duty cutting conditions
Process: After the heat, hard turning the outer circle of the large gear4,Heavy duty cutting
conditions (the vertical car) is recommended the solid CBN tools BN-S20 grade has the advantage that it can withstand
the tooth surface impact during hard turning, and the cutting performance is stable and cost-effective.
Heavy duty cutting gear comparison result
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Processing part: gear outer circle
(strong intermittent cutting)
Gear hardness: HRC60
Tool type:BN-S20 SNMN120712
Parameters: Cutting speed (Vc)=90m/min,
Feed rate(Fr)=0.12mm/r,
Cutting depth(ap)=2.5mm
Processing method: dry cutting
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Tool material
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Cutting speed (Vc) m/min
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Tool life
pcs/edge
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Failure form
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Halnn BN-S20
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90
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5
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Normal abrasion
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a brand of ceramic blades
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45 |
0.3 |
Collapse |