Sandvik Coromant 7861236 Turning Insert TNMM432-PR 4425

Product Description

The SANDVIK COROMANT 7861236 is a TNMM432-PR solid carbide turning insert in the T-Max P series, designed for external and internal turning operations on CNC lathes and turning centers. The insert features a triangular shape with a 60-degree included angle, a 0.5 inch inscribed circle, and a 0.0313 inch (1/32 inch) corner radius. It carries a CVD-applied multilayer coating consisting of Al2O3, TiN, and TiCN over a carbide substrate graded 4425. This combination delivers wear resistance and thermal stability suited to continuous and interrupted cuts in steel and cast iron applications. A neutral hand orientation makes it compatible with a wide range of standard toolholders using clamp or screw holding methods.

This insert is intended for production turning on steel and cast iron workpieces, corresponding to ISO material groups P and K. Typical applications include shaft turning, facing, and general-purpose profiling in both light and moderate material removal scenarios. The PR chip breaker geometry is engineered to handle a range of depths of cut and feed rates commonly encountered in production environments. Machinists and CNC operators in job shops, manufacturing facilities, and production lines will find this insert well suited to medium-duty turning programs where consistent edge life and chip control are priorities.

Key Features

• CVD multilayer coating: Al2O3, TiN, and TiCN for wear resistance and thermal protection
• Grade 4425 carbide substrate optimized for steel (ISO P) and cast iron (ISO K) cutting
• PR chip breaker geometry for controlled chip formation across a range of feeds and depths
• Triangular insert shape with 3 usable cutting edges to extend tool economy
• Neutral hand orientation compatible with standard TNMM-style toolholders
• Clamp and screw holding method compatibility for secure, repeatable seating

Compatibility

Designed for use in TNMM-style toolholders accepting a 0.5 inch inscribed circle triangular insert with a 0.2030 inch hole diameter. ISO code TNMM 22 04 08-PR 4425. Compatible with standard TNMM 432-style seats using clamp or screw clamping. Primary workpiece materials are steel (ISO P) and cast iron (ISO K).

Installation Notes

Insert replacement should be performed by a qualified machinist or CNC setup technician with the machine powered down, spindle locked, and all motion axes at rest. Use the appropriate torque wrench and manufacturer-specified clamping hardware when seating the insert to ensure proper contact with the toolholder pocket. Inspect the insert pocket for wear, debris, or damage before installing a new insert, as a compromised seat will reduce edge life and dimensional accuracy. Dispose of worn carbide inserts in accordance with local regulations for carbide and heavy-metal materials.