Korloy TNMG160404-HM NC3120 (TNMG 331-HM) High-Wear Resistant Steel Insert (10pcs)
Price shown is a starting point. Contact us for a precise quote based on your requirements.
The Original Korloy TNMG160404-HM NC3120 (ANSI: TNMG 331-HM) is a premium Triangular Turning Insert engineered for High-Precision Steel Machining (P-Group). Utilizing the advanced NC3120 Grade, this insert features a specialized CVD coating with superior adhesion and hardness, making it ideal for Alloy Steels, Mold Steels, and Pre-hardened Steels. The HM Chipbreaker and 0.4mm corner radius provide excellent chip control and surface finish in high-speed, continuous cutting applications.
Engineered for Speed & Durability: NC3120 is designed to thrive where heat and friction are at their peak. Its ultra-smooth coating reduces crater wear and friction heat, allowing you to push your CNC machine to higher RPMs while maintaining a stable tool life on tough alloy steels.
Technical Specifications (Metric & Imperial):
| ISO Designation | TNMG 160404-HM |
| ANSI Designation | TNMG 331-HM |
| 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 (Ultra-Wear Resistant CVD for Alloy Steel) |
Core Performance Benefits:
- Superior Wear Resistance: Thick, multi-layered CVD coating specifically optimized for alloy and hardened steel components.
- Stable Chip Management: HM geometry ensures reliable chip breaking even at varying depths of cut.
- Mirror-Like Finishes: The R0.4 tip radius provides tight tolerances and smooth surface textures for high-precision semi-finishing.
- Economical 6-Edge Design: Double-sided insert maximizes productivity and minimizes cost-per-edge.
Recommended Cutting Parameters:
| Material Group | Cutting Speed (Vc) | Feed Rate (fn) | Depth of Cut (ap) |
|---|---|---|---|
| Alloy Steel (4140/4340) | 180-320 m/min (590-1050 sfm) | 0.08-0.28 mm/rev (.003-.011 ipr) | 0.4-3.5 mm (.016-.138") |
| Pre-hardened Steel (HRC 30-40) | 120-220 m/min (390-720 sfm) | 0.08-0.22 mm/rev (.003-.009 ipr) | 0.4-2.5 mm (.016-.100") |
Compatible Tooling Systems:
- External Precision Holders: MTJNR 2020K16 / MTJNR 2525M16 (ANSI 12-4B / 16-4D)
- Internal Precision Bars: S25S-WTJNR16 / S32T-WTJNR16
Machinist Tip: NC3120 vs. NC3020
When to upgrade to NC3120:
Best for Heat Resistance. NC3120 is your go-to for harder alloy steels. It stays sharp longer under the high temperatures generated by cutting materials like 4140 or pre-hardened tool steels.
Best for Versatility. For standard carbon steels (1045, A3) and general maintenance work, NC3020 provides a balanced performance. Switch to NC3120 only when you need extra wear protection.
Pro Advice: The TNMG160404 (331) version is a precision tool. For best results in alloy steel, use constant surface speed (CSS) to maintain a consistent finish and prevent the tool from work-hardening the material.
Packaging: 10 pieces per box.
TNMG 160404-HM for hardened steel, Korloy NC3120 grade specifications, best inserts for 4340 pre-hardened steel, long life TNMG 331-HM inserts, high speed finishing inserts for steel
Technical FAQ & Buying Guide
Absolutely. Our CNC carbide inserts (including CNMG, WNMG, DNMG, and APMT series) are manufactured strictly adhering to international ISO/ANSI specifications. A CNMG 120408 from OYYU BEYOND will flawlessly fit any standard turning tool holder or indexable tool from major global brands like Sandvik Coromant, Kennametal, Iscar, Walter, or SECO, providing a highly cost-effective premium alternative without sacrificing tolerance or tool life.
We offer optimized CVD and PVD multi-layer coatings for different ISO material groups:
- For Carbon/Alloy Steel (ISO P): Choose our thick multi-layer CVD coated grades (e.g., Al2O3 + TiN). They provide exceptional crater wear resistance and thermal barriers during high-speed dry or wet roughing.
- For Stainless Steel (ISO M): Choose our nano-structured PVD coated grades with sharp, positive chipbreakers (like -TM or -MA). This combination prevents work hardening and effectively controls sticky chips.
The optimal cutting parameters vary depending on the workpiece hardness and operation type:
- For General Steel Turnings: Recommended cutting speed ($V_c$) ranges from 150 to 280 m/min, with a feed rate ($f$) of 0.15 to 0.45 mm/rev.
- For Stainless Steel Finishing: Recommended cutting speed ($V_c$) is 120 to 200 m/min, with a feed rate ($f$) of 0.10 to 0.25 mm/rev.Always adjust parameters based on early wear patterns: increase $V_c$ if built-up edge occurs, or reduce $V_c$ if severe flank wear is observed.
Yes, we support machine shops, distributors, and global buyers with tiered wholesale pricing and competitive volume discounts. We also provide OEM custom manufacturing solutions for tool holders and carbide inserts based on your technical drawings. Contact our team to request a quick B2B quotation.
We provide secure worldwide express shipping (via DHL, FedEx, and UPS) with specialized, vibration-proof industrial packaging to ensure tools arrive in perfect condition. In-stock items are dispatched within 24-48 hours, while custom or bulk orders typically have a stable lead time of 15-25 days.
All our cutting tools and tool holders are manufactured strictly in accordance with ISO 9001 and international industrial standards. Every batch undergoes 100% rigorous quality control testing using high-precision optical measuring equipment to ensure reliable tool life and stable performance in continuous mass production.