Kennametal 1818857 Grooving Insert NR4125K KC5025 Carbide

Product Description

The KENNAMETAL 1818857 is a solid carbide grooving insert designed for precision external grooving and parting operations on CNC lathes and turning centers. Manufactured to the NR4125K insert style in KENNAMETAL grade KC5025, this insert features a TiAlN coating applied via PVD process, delivering strong wear resistance and thermal stability at elevated cutting speeds. The insert has a 6.35 mm (0.250 inch) cutting width and a 6.35 mm (0.250 inch) maximum depth of cut, with a full-radius corner profile measuring 3.18 mm (0.125 inch). A positive rake angle of 10 degrees and a K-style chip breaker promote clean chip evacuation and controlled cutting forces. Installed by machinists and CNC operators in production and job-shop environments.

This insert is suited for grooving operations on steel, alloy steel, and similar materials where a carbide grade with PVD TiAlN coating provides the right balance of hardness and toughness. The Top Notch series mounting system is a right-hand configuration, designed to seat securely in compatible Top Notch toolholders. It is applicable to both roughing and finishing groove profiles within its specified depth-of-cut range of 5.00 mm to 10.00 mm (0.200 inch to 0.300 inch). Insert seat size 4 and insert size 4125 define the holder interface for this part.

Key Features

• Solid carbide construction with PVD TiAlN coating for wear and heat resistance
• 6.35 mm cutting width and 6.35 mm maximum depth of cut
• Full radius corner profile at 3.18 mm (0.125 inch) radius
• Positive 10-degree rake angle with K-style chip breaker for controlled chip flow
• Right-hand insert orientation for standard Top Notch toolholder compatibility
• Material grade C2 and C6 classification for versatile ferrous machining applications

Compatibility

Designed for use with Top Notch series toolholders accepting insert seat size 4 and insert style NR. The MSC and manufacturer cross-reference number for this insert is NR4125R/LK.

Installation Notes

Installation should be performed by a qualified machinist or CNC tooling technician. Before changing inserts, ensure the machine spindle is fully stopped and the machine is placed in a safe, locked-out state per shop safety procedures. Use the appropriate torque wrench and seating tool specified for the Top Notch clamping system to secure the insert without over-tightening. Inspect the insert pocket and clamping hardware for wear or debris before seating the new insert.