Korloy TNMG220408-HM NC3020 (TNMG 432-HM) Heavy Duty Steel Turning Insert (10pcs)
30-Day Free Returns
Free Worldwide Shipping
The Original Korloy TNMG220408-HM NC3020 (ANSI: TNMG 432-HM) is a heavy-duty Double-Sided Triangular Turning Insert specifically engineered for high-productivity Steel Machining (P-Group). Utilizing the advanced NC3020 CVD Coating, it offers exceptional resistance to high temperatures and crater wear. The HM (Medium Cutting) Chipbreaker combined with a 22mm cutting edge ensures maximum stability and reliable chip control during deep passes on large components.
Maximum Material Removal: TNMG220408 is the powerhouse of the TNMG family. With its larger carbide substrate and 0.8mm (1/32") radius, it excels in roughing and semi-finishing of large steel castings, forgings, and shafts where smaller inserts would fail due to heat or pressure.
Technical Specifications (Metric & Imperial):
| ISO Designation | TNMG 220408-HM |
| ANSI Designation | TNMG 432-HM |
| Inscribed Circle (IC) | 12.7 mm / (1/2") |
| Thickness (S) | 4.76 mm / (3/16") |
| Corner Radius (r) | 0.8 mm / (1/32") |
| Grade | NC3020 (Top Performance CVD for Steel) |
Core Performance Benefits:
- Enhanced Heat Dissipation: The larger 22mm geometry absorbs and dissipates cutting heat more efficiently, extending tool life during long, continuous cuts.
- Robust HM Chipbreaker: Designed for medium-to-heavy ranges, ensuring chips are broken safely away from the workpiece.
- Superior Edge Toughness: The 0.8mm radius provides the optimal balance between surface finish and the ability to handle interrupted cuts or hard scale.
- Cost Efficiency: Features 6 precision cutting edges for maximum economic throughput.
Recommended Cutting Parameters:
| Material Group | Cutting Speed (Vc) | Feed Rate (fn) | Depth of Cut (ap) |
|---|---|---|---|
| Carbon Steel (1045 / 45#) | 180-350 m/min (590-1150 sfm) | 0.15-0.50 mm/rev (.006-.020 ipr) | 1.0-6.0 mm (.040-.236") |
| Alloy Steel (4140 / 42CrMo) | 150-300 m/min (490-985 sfm) | 0.15-0.45 mm/rev (.006-.018 ipr) | 1.0-5.0 mm (.040-.197") |
Compatible Tooling Systems:
Requires heavy-duty 22-size (4-size ANSI) holders:
- External Lathe Holders: MTJNR 2525M22 / MTJNR 3232P22 (ANSI 16-4D / 20-4E)
- Heavy Boring Bars: S40U-WTJNR22 / S50V-WTJNR22
Machinist Tip: The "Big Steel" Rule
Optimizing the TNMG220408 for steel production:
The Ultimate Standard. This is the most reliable choice for heavy turning. If your machine has the power, this insert can significantly reduce cycle times by allowing for aggressive feed rates and deeper passes.
If you are facing extreme interrupted cuts or rough castings with heavy scale, consider moving up to a 1.2mm radius. However, for 90% of large steel parts, the 0.8mm (this model) provides the best balance of finish and strength.
Pro Advice: NC3020 is designed for high surface speeds. For large workpieces, maintain consistent cutting speed (SFM) as the diameter changes to ensure uniform chip breaking and tool wear.
Packaging: 10 pieces per box.
TNMG 220408-HM for heavy roughing, Korloy NC3020 CVD coated insert benefits, best insert for large steel shaft turning, TNMG 432-HM cutting data for alloy steel, industrial grade triangular carbide inserts