Sandvik Coromant 7859259 Turning Insert DNMG432-PR 4415

Product Description

The SANDVIK COROMANT 7859259 is a DNMG432-PR 4415 turning insert designed for external turning operations on CNC lathes and turning centers. It features a 55-degree diamond insert shape with a neutral hand orientation and four cutting edges, maximizing tool life per insert. The carbide substrate carries a CVD-applied multilayer coating of TiCN, Al2O3, and TiN, which provides wear resistance and thermal protection during continuous and interrupted steel cutting. The 0.79 mm corner radius and PR chip breaker geometry are engineered for controlled chip formation at moderate to high feed rates. Licensed machinists and CNC operators install this insert as a direct replacement in T-Max P compatible toolholders.

This insert is suited for turning steel and cast iron workpieces in both roughing and semi-finishing applications. The PR chip breaker is optimized for primary use on steel (ISO P) and secondary use on cast iron (ISO K) at moderate depths of cut and feed. It is a standard choice in job shop and production turning environments where consistent chip control and predictable tool life are required. The ISO code for this insert is DNMG 15 04 08-PR 4415, and it is cataloged by the manufacturer as DNMG 432-PR 4415.

Key Features

• CVD multilayer coating: TiCN, Al2O3, and TiN for extended wear resistance
• 55-degree diamond insert shape with 4 usable cutting edges
• 0.79 mm (0.0313 inch) corner radius for balanced edge strength and surface finish
• PR chip breaker optimized for steel and cast iron turning
• Neutral hand orientation fits both left- and right-hand toolholder setups
• Compatible with clamp and screw insert holding methods

Compatibility

Designed for use with T-Max P series turning toolholders accepting DNMG 15 04 08 style inserts. Compatible with toolholders using clamp or screw clamping methods. Primary workpiece material is steel (ISO P); secondary workpiece material is cast iron (ISO K).

Installation Notes

CNC machinists and toolroom technicians install turning inserts. Power down and lock out the machine spindle before indexing or replacing inserts. Use the appropriate torx or hex key to seat the insert firmly against the pocket seat and clamping mechanism — do not overtighten the clamp screw. Inspect the insert pocket for chips or debris before seating a new insert to ensure accurate positioning and prevent edge chipping.