Kennametal 4050402 CNMG431MS KCU25 Carbide Turning Insert

Product Description

The KENNAMETAL 4050402 is a CNMG431MS indexable turning insert in the KCU25 manufacturer grade, coated with AlTiN via a PVD process for wear resistance at elevated cutting temperatures. The insert is solid carbide with a negative rake geometry, an 80-degree diamond shape, and a honed cutting edge style. It measures 12.9 mm (0.5077 inches) in length with a 0.5-inch inscribed circle and a 1/64-inch (0.0156-inch) corner radius. The insert thickness is 3/16 inch (0.1875 inches). It provides 4 cutting edges per insert and is designed for turning, facing, and boring operations performed by machinists and CNC operators in production and job-shop environments.

This insert is engineered for primary use on steel, stainless steel, superalloys, and titanium workpiece materials, corresponding to ISO material codes P, M, and S. The KENLOC series CNMG style with an MS chip breaker geometry is suited for medium finishing to light roughing passes. The ISO designation for this insert is CNMG120404MS, and it carries both ANSI and ISO standard compliance. It is held in the toolholder using a clamp-and-pin method, making it compatible with standard CNMG toolholders.

Key Features

• AlTiN PVD coating for high-temperature and wear-resistant performance on steel and superalloys
• 80-degree diamond (CNMG) insert shape with negative rake for strong edge support
• MS chip breaker geometry optimized for medium finishing to light roughing
• 4 usable cutting edges per insert for extended tool economy
• Honed cutting edge style reduces micro-chipping on difficult materials
• Multi-use application: turning, facing, and boring from a single insert geometry

Compatibility

Designed as a direct-fit replacement for CNMG431MS (ISO: CNMG120404MS) toolholders using a clamp-and-pin insert-holding method. Compatible with standard KENLOC series toolholders configured for CNMG style inserts. Verify toolholder pocket geometry before installation.

Installation Notes

Installation is performed by qualified machinists or CNC tooling technicians. Power down and lock out the machine spindle before changing inserts. Use the appropriate torx or hex key to release the clamp screw; do not overtighten when seating the new insert, as this can fracture the carbide substrate. Inspect the toolholder pocket for chips or debris before seating and confirm the insert is fully seated and clamped before resuming cuts.