Sandvik Coromant 7861084 Turning Insert DNMG331-QM 4425

Product Description

The SANDVIK COROMANT 7861084 is a DNMG331-QM turning insert in the T-Max P series, manufactured from solid carbide and coated via CVD with Al2O3, TiN, and TiCN layers. This insert carries the ISO designation DNMG 11 04 04-QM 4425 and is designed for external turning operations on steel and cast iron. The 55-degree diamond shape provides a balance of strength and edge access, while the QM chip breaker geometry supports controlled chip evacuation across a range of cutting conditions. With a 3/8 inch inscribed circle and a 0.4 mm corner radius, this insert fits standard DNMG-style toolholders and is installed by machinists and CNC lathe operators in production and job-shop environments.

This insert is suited for turning steel and cast iron workpieces in both roughing and medium finishing passes. The QM chip breaker geometry is optimized for work materials in ISO P and ISO K material groups. The neutral hand orientation makes it compatible with a wide range of DNMG toolholder configurations. The insert is sold individually but requires a minimum order quantity of 10 units, making it appropriate for shop stock or toolcrib replenishment. It is used in horizontal and vertical CNC turning centers as well as manual engine lathes equipped for indexable insert tooling.

Key Features

• CVD coating combining Al2O3, TiN, and TiCN layers for wear resistance and thermal stability on steel and cast iron
• Manufacturer grade 4425 optimized for ISO P steel and ISO K cast iron workpiece materials
• QM chip breaker geometry for controlled chip formation across a range of depths of cut and feed rates
• 55-degree diamond insert shape with 4 cutting edges for multiple indexes per insert
• 0.4 mm corner radius (0.0156 inch) for surface finish control in medium to finish turning passes
• Compatible with clamp and screw insert holding methods in standard DNMG toolholders

Compatibility

Designed for use in DNMG-style indexable turning toolholders that accept inserts with a 3/8 inch inscribed circle, 3/16 inch insert thickness, and a 0.150 inch hole diameter. Compatible with clamp and screw holding methods. Intended for ISO P primary workpiece materials (steel) and ISO K secondary workpiece materials (cast iron).

Installation Notes

Installation is performed by machinists using the appropriate torx or hex key to seat the insert with the specified holding method, either clamp or screw. The machine spindle must be fully stopped and the toolholder secured in the turret before indexing or replacing an insert. Inspect the insert pocket and seating surface for chips or debris before installing a new edge to ensure proper seating and edge repeatability. Follow the toolholder manufacturer guidelines for clamping torque to avoid insert cracking or improper seating.