Korloy VBMT110304-HMP NC3020 (ANSI VBMT 221-HMP) CVD Carbide Insert for Steel (10pcs)
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The Original Korloy VBMT110304-HMP NC3020 (ANSI Cross Reference: VBMT 221-HMP) is a high-performance 35° Rhombic Positive Insert specifically optimized for Medium-Finishing of Steel. Featuring the innovative HMP (Harmony Medium-Positive) chipbreaker, it offers superior chip control and reduced cutting forces. The NC3020 CVD Coated Grade provides an ideal balance of wear resistance and toughness, making it the industry standard for stable production in carbon and alloy steels.
Superior Chip Control: The HMP chipbreaker is designed with a specialized 3D geometry that ensures stable chip evacuation even at varying depths of cut, preventing the "bird-nesting" common in ductile steel machining.
Technical Specifications:
| ISO Designation | VBMT 110304-HMP |
| ANSI Designation | VBMT 221-HMP |
| Inscribed Circle (IC) | 6.35 mm / (1/4") |
| Thickness (S) | 3.18 mm / (1/8") |
| Corner Radius (r) | 0.4 mm / (1/64") |
| Grade | NC3020 (CVD Coated) |
| Primary Material | Steel (P10-P30) |
Core Performance Benefits:
- Optimized CVD Coating: The Al2O3 coating layer provides excellent heat shield and oxidation resistance for high-speed operation.
- HMP Chipbreaker: Lower cutting resistance allows for higher feeds without compromising tool life or surface finish.
- Versatile Application: Suitable for both continuous and light interrupted cutting in a wide variety of steel types.
- Visible Wear: The gold-colored TiN top layer makes it easy to identify edge wear, preventing premature tool changes.
Recommended Cutting Parameters:
| Workpiece Material | Cutting Speed (Vc) | Feed Rate (fn) | Depth of Cut (ap) |
|---|---|---|---|
| Carbon Steel / Alloy Steel | 150 - 300 m/min | 0.03 - 0.20 mm/rev | 0.15 - 2.70 mm |
| Mild Steel (A36 / 1018) | 180 - 350 m/min | 0.05 - 0.18 mm/rev | 0.20 - 2.00 mm |
Compatible Tooling Systems:
Fits all standard 35° rhombic positive tool holders (5° relief), including:
- External Turning: SVJBR / SVVBN / SVHBR Series
- Internal Boring: S-SVUBC / S-SVQBC Boring Bars
Machinist Tip: The "Steel Universal" Setup
Why NC3020 is your best daily driver:
When machining forged steel with hard outer "skin," the NC3020 substrate prevents chipping at the depth-of-cut line, while the HMP breaker manages the transition to the softer interior material perfectly.
The 0.4mm (1/64") radius is the sweet spot for achieving tight tolerances and Ra finishes below 1.6µm. For even better finishes in high-speed applications, ensure your feed rate is around 0.1mm/rev.
Packaging: 10 pieces per box.
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