Sandvik Coromant 7860998 Turning Insert SNMG642-PR 4425

Product Description

The SANDVIK COROMANT 7860998 is a SNMG-style indexable turning insert from the T-Max P series, designed for external and internal turning operations on CNC lathes and turning centers. It carries manufacturer grade 4425 carbide substrate with a CVD-applied multilayer coating of Al2O3, TiCN, and TiN, delivering wear resistance and thermal stability at elevated cutting speeds. The insert features a square shape with a 3/4 inch inscribed circle and a 1/32 inch corner radius, offering eight usable cutting edges per insert. It is installed and indexed by licensed machinists and CNC operators during production or maintenance turning work.

This insert is engineered primarily for steel (ISO material code P) with a secondary application in cast iron (ISO material code K). It suits general-purpose and finish turning in both high-production and job-shop environments where consistent tool life and predictable chip control are required. The PR chip breaker geometry supports a wide range of depths of cut and feed rates on steel components. The neutral hand orientation allows use on standard right-hand and left-hand toolholders configured for SNMG seating.

Key Features

• CVD multilayer coating: Al2O3, TiCN, and TiN for thermal and abrasion resistance
• Square insert shape (SNMG) with eight available cutting edges per insert
• 3/4 inch (0.7500 inch) inscribed circle for robust depth-of-cut capacity
• 1/32 inch (0.0313 inch) corner radius for balanced edge strength and surface finish
• PR chip breaker optimized for steel and cast iron turning
• Compatible with clamp and screw insert holding methods
• ISO code SNMG 19 06 08-PR 4425 for cross-reference sourcing

Compatibility

Designed for use in SNMG-style toolholders that accept a square insert with a 3/4 inch inscribed circle, 1/4 inch insert thickness, and a 0.3120 inch hole diameter. Compatible holding methods include clamp and screw styles. Verify toolholder pocket geometry and clearance code N seating requirements before installation.

Installation Notes

Installation is performed by a qualified machinist or CNC operator. Power down and lock out the machine spindle before indexing or replacing inserts. Use the correct torque wrench and manufacturer-specified clamping hardware to seat the insert securely in the pocket; do not overtighten or use improvised tools on the clamp screw. Inspect the toolholder pocket for wear or debris before seating a new insert, as a damaged pocket will reduce edge life and dimensional accuracy.