Sandvik Coromant 7860816 Turning Insert DCMT21.51-PM 4425

Product Description

The SANDVIK COROMANT 7860816 is a DCMT-style solid carbide turning insert in the CoroTurn 107 series, designed for precision external turning operations on CNC lathes and turning centers. It carries a CVD-applied multilayer coating of TiCN, Al2O3, and TiN, which provides wear resistance, thermal stability, and edge durability across a range of cutting conditions. The insert features a 55-degree diamond shape, a 0.4 mm corner radius, and a neutral hand orientation. It is sized with a 1/4-inch inscribed circle and a 3/32-inch thickness, making it a compact insert suited for finishing and semi-finishing passes on steel and cast iron workpieces.

This insert is intended for use in CoroTurn 107 toolholders configured for DCMT-style inserts. It is best suited for turning steel (ISO material group P) as the primary workpiece material, with cast iron (ISO material group K) as a secondary application. The PM chip breaker geometry supports controlled chip formation in finishing and light semi-finishing cuts, making this insert a practical choice for production turning on both CNC and manual lathes where surface finish and dimensional accuracy are priorities. Installation is performed by licensed machinists and CNC operators in production and job-shop environments.

Key Features

• CVD multilayer coating: TiCN, Al2O3, and TiN for extended tool life on steel and cast iron
• 55-degree diamond insert shape with 7-degree relief angle for clearance in turning applications
• PM chip breaker geometry for controlled chip evacuation in finishing and semi-finishing cuts
• Two cutting edges per insert for cost-effective tooling use
• Clamp and screw holding method compatible with standard CoroTurn 107 toolholders
• ISO code DCMT 07 02 04-PM 4425 for cross-reference with standard insert catalogs

Compatibility

Designed for use in CoroTurn 107 series toolholders accepting DCMT-style inserts with a 1/4-inch inscribed circle. ISO designation DCMT 07 02 04-PM 4425 may be used for toolholder cross-reference. Manufacturer catalog number is DCMT 2(1.5)1-PM 4425.

Installation Notes

This insert is installed and indexed by a qualified machinist or CNC operator. Power down and lock out the spindle before seating or indexing the insert. Use the appropriate torque wrench and insert key to secure the clamping screw or clamp without overtightening, which can fracture the carbide substrate. Inspect the seating pocket for chips or debris before installing a fresh cutting edge.