Sandvik Coromant 6868578 Turning Insert CNMA431-KR 3225

Product Description

The SANDVIK COROMANT 6868578 is a CNMA-style solid carbide turning insert designed for precision external and internal turning operations on CNC lathes and turning centers. This insert carries a CVD-applied multilayer coating of TiCN, Al2O3, and TiN, which delivers strong wear resistance and thermal protection at the cutting edge. It features an 80-degree diamond insert shape, a 1/2-inch inscribed circle (IC), and a 1/64-inch corner radius. The neutral-hand orientation and rounded cutting edge style make it well-suited for medium to heavy stock removal passes. The KR chip breaker geometry is engineered specifically for cast iron workpiece materials. Licensed machinists and CNC operators install and index these inserts as part of routine tooling maintenance.

This insert belongs to SANDVIK COROMANT's T-Max P series and is intended for turning applications where the primary workpiece material is cast iron. The ISO code for this insert is CNMA 12 04 04-KR 3225. With four available cutting edges per insert and a clamp-and-pin holding method, it is used in production turning environments where consistent tool life and predictable chip control are required. Typical applications include roughing and semi-finishing passes on cast iron components in automotive, heavy equipment, and general machining operations.

Key Features

• CVD multilayer coating: TiCN, Al2O3, and TiN for wear and heat resistance on cast iron
• KR chip breaker geometry optimized for cast iron workpiece materials
• 80-degree diamond insert shape (CNMA style) with rounded cutting edge
• Four usable cutting edges per insert for extended tooling value
• Clamp and pin insert holding method for secure seating in compatible toolholders
• 1/64-inch corner radius (0.0156 inch / 0.40 mm) for controlled edge definition

Compatibility

This insert conforms to ISO code CNMA 12 04 04-KR 3225 and fits toolholders designed for CNMA 431 inserts with a clamp-and-pin holding method. It is part of the SANDVIK COROMANT T-Max P series. Verify toolholder seat geometry and clamping system compatibility before installation.

Installation Notes

Insert indexing and replacement should be performed by a qualified machinist or CNC operator with the spindle fully stopped and the machine in a locked-out, tagged-out state per applicable safety procedures. Use the correct torque wrench and clamp hardware specified for the toolholder to avoid seat damage or insert fracture. Inspect the insert pocket for chips, debris, or wear before seating a new insert. Do not force or strike the insert during installation.