Sandvik Coromant 7860871 Turning Insert DCMT32.51-UM

Product Description

The SANDVIK COROMANT 7860871 is a solid carbide turning insert in the DCMT style, designed for precision turning operations on CNC lathes and turning centers. It carries a CVD-applied multilayer coating of TiCN, Al2O3, and TiN, which provides thermal resistance, wear resistance, and a low-friction outer surface. The insert features a 55-degree diamond shape (Insert Shape Code D), a 3/8-inch inscribed circle, and a 0.40 mm corner radius. The UM chip breaker geometry promotes reliable chip control across a range of feed rates and depths of cut. This insert is installed by machinists and CNC operators working in production turning environments.

This insert is suited for turning steel as its primary workpiece material and cast iron as a secondary workpiece material, consistent with its ISO grade 4425 designation and P/K material group ratings. It is part of the CoroTurn 107 series, which is engineered for external and internal turning with positive cutting geometries. Typical applications include finishing and semi-finishing passes on ferrous components in job shop and production settings. The neutral hand orientation allows use in standard right-hand toolholders configured for DCMT-style inserts.

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 (Clearance Code C) for positive, free-cutting action
• 0.40 mm corner radius balances edge strength with surface finish quality
• UM chip breaker geometry for consistent chip control in steel turning
• Two cutting edges per insert for cost efficiency
• Screw and clamp compatible holding method for secure seating in toolholders

Compatibility

Designed for use in DCMT-style toolholders within the CoroTurn 107 series. ISO code DCMT 11 T3 04-UM 4425. Compatible toolholders must accept a 3/8-inch inscribed circle insert with a 4.40 mm hole diameter and DCMT seating geometry. Verify toolholder specifications before installation.

Installation Notes

Installation is performed by a qualified machinist or CNC setup technician. Power down and lock out the machine spindle before changing inserts. Seat the insert fully against the pocket locating surfaces before tightening the clamp or screw to the toolholder manufacturer's specified procedure. Inspect the insert pocket and shim for damage or debris before each insert change to avoid seating errors that can cause premature edge failure.