Sumitomo NCTPGX21.51 BNC300 CBN Triangular Turning Insert
Couldn't load pickup availability
Use this text to encourage communication or promote sharing on social networks.
The Sumitomo Electric NCTPGX21.51 is a triangular (T = 60° equilateral) CBN (Cubic Boron Nitride) turning insert in grade BNC300, a Sumitomo sintered CBN grade engineered for continuous and light-interrupted turning of hardened steels (typically 45–65 HRC) and hard-turning applications where conventional carbide lacks wear resistance. Decoding the ISO-style designation: N = special/non-standard geometry, C = CBN material designator, T = triangular shape (60°), P = 11° clearance angle, G = close tolerance, X = special chipbreaker geometry, 2 = insert size (IC ≈ 1/4 in / 6.35 mm), 1.51 = thickness/nose radius variant (thickness ~3/32 in, nose radius 1/64 in). The BNC300 grade features a fine-grain CBN sintered tip brazed or clamped to a carbide substrate, providing superior hardness, thermal stability up to ~1000 °C, and excellent surface finish capability on hardened ferrous workpieces; it is rated for continuous cut (as indicated by the "Cont." marking on the package label) and is compatible with TPGX-style toolholders accepting this insert size. Sold new in original Sumitomo Electric factory packaging, quantity 1 per box, inspected and verified by Sumitomo Electric.
Product Specifications
| Brand | Sumitomo Electric |
| MPN | NCTPGX21.51 |
| Grade | BNC300 |
| Material | CBN (Cubic Boron Nitride) |
| Insert Shape | Triangular, 60° (T) |
| Clearance Angle | 11° (P) |
| Tolerance Class | G (close tolerance) |
| Chipbreaker | X (special geometry) |
| Insert Size (IC) | ~1/4 in (6.35 mm) |
| Nose Radius | 1/64 in (0.4 mm) |
| Cut Type | Continuous |
| ISO Material Group | H (hardened steel) |
| Workpiece Hardness | 45–65 HRC |
| Coating | Uncoated (sintered CBN) |
| Qty per Package | 1 |
| Condition | New |