Korloy VBMT160404-HMP NC3120 (ANSI VBMT 331-HMP) Next-Gen CVD Carbide Insert (10pcs)
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The Original Korloy VBMT160404-HMP NC3120 (ANSI Cross Reference: VBMT 331-HMP) is the latest evolution in 35° Rhombic Positive Inserts for Professional Steel Machining. Designed to surpass the performance of the legendary NC3020, the NC3120 Grade features a cutting-edge CVD coating with superior adhesion and a specialized substrate that absorbs mechanical shock. The HMP (Harmony Medium-Positive) chipbreaker ensures excellent chip control, making it the premier choice for semi-finishing carbon and alloy steels.
The Stability Advantage: The 1604 series provides 50% more mass than the 1103 series, drastically reducing chatter and heat deformation. When paired with the NC3120's upgraded toughness, this insert provides the most predictable tool life in the Korloy lineup.
Technical Specifications (Metric & ANSI):
| ISO Designation | VBMT 160404-HMP |
| ANSI Designation | VBMT 331-HMP |
| Inscribed Circle (IC) | 9.525 mm / (3/8") |
| Thickness (S) | 4.76 mm / (3/16") |
| Corner Radius (r) | 0.4 mm / (1/64") |
| Grade | NC3120 (New Era CVD) |
| Primary Application | Steel (P15 - P35) |
Core Performance Benefits:
- Advanced CVD Technology: A more refined TiCN and Al2O3 layer structure offers better protection against crater wear and thermal cracking than previous generations.
- Optimized Substrate: NC3120 features improved resistance to plastic deformation, allowing for consistent performance even as cutting temperatures rise.
- HMP Chipbreaker Excellence: Optimized for medium cutting, the 3D geometry reduces cutting forces and ensures chips are curled and broken away from the workpiece surface.
- High Edge Security: The combination of the 16-size body and NC3120 grade makes this insert exceptionally reliable for light interruptions.
Recommended Cutting Parameters:
| Workpiece Material | Cutting Speed (Vc) | Feed Rate (fn) | Depth of Cut (ap) |
|---|---|---|---|
| Alloy Steel (4140/4340) | 150 - 330 m/min | 0.08 - 0.22 mm/rev | 0.5 - 3.0 mm |
| Tool Steel / Mold Steel | 120 - 250 m/min | 0.07 - 0.20 mm/rev | 0.5 - 2.5 mm |
Compatible Tooling Systems:
Precision-matched for VBMT 1604 positive tool holders:
- External Profile Tooling: SVJBR 2020K16 / SVJBR 2525M16
- Heavy-Duty Boring: S32T-SVUBR16 / S40U-SVQBR16
Machinist Tip: The 1604 Advantage
Optimizing for larger steel components:
Because the VBMT 1604 is thicker than the 1103, you can push it harder without risking insert breakage. This extra stability translates directly into a more consistent surface finish on alloy steels.
NC3120 is excellent for dry machining. However, for the best surface Ra, use high-pressure coolant directed at the tip to clear the HMP-generated chips quickly.
Packaging: 10 pieces per box.
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