Sandvik Coromant 7859185 Turning Insert DNMG442-QM 4415

Product Description

The SANDVIK COROMANT 7859185 is a DNMG442-QM 4415 indexable turning insert designed for metal-cutting lathe operations in production and job-shop environments. It features a solid carbide substrate with a CVD-applied multilayer coating of TiCN, Al2O3, and TiN, a combination that provides wear resistance, thermal shielding, and reduced built-up edge when turning steel and cast iron. The insert has a 55-degree diamond shape, a 0.5000-inch inscribed circle, and a 0.79 mm corner radius. The QM chip breaker geometry is engineered for medium to rough turning passes where chip control and cutting-edge stability are critical. Installation is performed by machinists and CNC operators in machine shops and manufacturing facilities.

This insert is suited for external and internal turning operations on steel (ISO P) as primary workpiece material and cast iron (ISO K) as secondary workpiece material. It fits into compatible T-Max P series toolholders that accept DNMG-style inserts with clamp and screw holding. With four cutting edges per insert, it offers multiple indexes before replacement, making it a cost-effective choice for high-volume turning programs. It is appropriate for both CNC turning centers and manual engine lathes running moderate to heavy depths of cut.

Key Features

• CVD multilayer coating: TiCN, Al2O3, and TiN for wear and thermal resistance
• 55-degree diamond insert shape (D) with neutral hand orientation
• QM chip breaker geometry optimized for medium to rough steel turning
• Four usable cutting edges per insert for extended tool life per piece
• Clamp and screw insert holding for secure seating under interrupted or heavy cuts
• ISO grade 4415 carbide substrate balanced for P and K workpiece material groups

Compatibility

Designed for use in T-Max P series toolholders accepting DNMG-style inserts with clamp or screw clamping. ISO code reference: DNMG 15 06 08-QM 4415. Compatible with toolholder systems requiring a 0.5000-inch (12.70 mm) inscribed circle DNMG insert with a 0.2030-inch hole diameter.

Installation Notes

Insert indexing and replacement is performed by a machinist or CNC operator with the machine fully stopped and the spindle locked out per facility lockout/tagout procedures. Use the appropriate Torx or hex key specified by the toolholder manufacturer when tightening the clamp or screw — do not overtighten, as carbide inserts are brittle and can crack under excessive clamping force. Inspect the toolholder pocket seat for chips or debris before seating a new insert. Verify insert orientation matches the neutral-hand designation of the toolholder before resuming cuts.