Korloy TNMG160408-HM NC3020 (TNMG 332-HM) Steel Turning Insert for General Purpose (10pcs)
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The Original Korloy TNMG160408-HM NC3020 (ANSI: TNMG 332-HM) is the quintessential "workhorse" for General Steel Machining (P-Group). Equipped with a thick, high-performance NC3020 CVD Coating, this insert is built for longevity in high-speed, continuous cutting environments. The HM (Medium Cutting) Chipbreaker and robust 0.8mm corner radius make it incredibly versatile, handling everything from semi-roughing to smooth semi-finishing on a vast range of carbon and alloy steels.
Global Workshop Standard: The 0.8mm (1/32") radius combined with the HM geometry is the most popular choice for general turning. It offers superior edge strength for 4140, 1045, and SCM440 steels, ensuring stable performance even when facing minor interruptions or scale.
Technical Specifications (Metric & Imperial):
| ISO Designation | TNMG 160408-HM |
| ANSI Designation | TNMG 332-HM |
| Inscribed Circle (IC) | 9.525 mm / (3/8") |
| Thickness (S) | 4.76 mm / (3/16") |
| Corner Radius (r) | 0.8 mm / (1/32") |
| Grade | NC3020 (Premium CVD for Steel) |
Core Performance Benefits:
- Supreme Wear Resistance: Thick Al2O3 CVD coating provides a robust thermal barrier, ideal for high-speed dry or wet machining.
- Stable HM Chipbreaker: Designed for medium cutting, it effectively controls chips across a broad range of depths and feed rates.
- Reinforced Edge Strength: The R0.8 radius handles higher cutting forces and provides longer tool life than smaller radii.
- Exceptional Economy: 6 usable cutting edges per insert, reducing the overall cost per part in production.
Recommended Cutting Parameters:
| Material Group | Cutting Speed (Vc) | Feed Rate (fn) | Depth of Cut (ap) |
|---|---|---|---|
| Low Carbon Steel (1020/A3) | 200-380 m/min (650-1250 sfm) | 0.15-0.45 mm/rev (.006-.018 ipr) | 0.8-4.5 mm (.032-.177") |
| Alloy Steel (4140/4340) | 160-320 m/min (525-1050 sfm) | 0.15-0.40 mm/rev (.006-.016 ipr) | 0.8-3.5 mm (.032-.138") |
Compatible Tooling Systems:
- Standard External Holders: MTJNR 2020K16 / MTJNR 2525M16 (ANSI 12-4B / 16-4D)
- Large Boring Bars: S32T-WTJNR16 / S40U-WTJNR16
Machinist Tip: The "Go-To" Setup
Why the TNMG160408-HM is the default choice:
Maximum Stability. If you don't know which insert to pick for a steel job, start with this one. It provides the best balance of tool life, chip control, and toughness for 90% of general turning tasks.
Switch to the 0.4mm version (TNMG160404-HM) only if you are experiencing vibration on long, thin shafts or if you need to finish a corner with a smaller radius requirement.
Pro Advice: NC3020 is optimized for speed. If you see built-up edge (material sticking to the tool), increase your cutting speed. If the edge is deforming, you've hit the thermal limit—try reducing the speed or adding high-pressure coolant.
Packaging: 10 pieces per box.
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