Sandvik Coromant 7861132 Turning Insert TCMT32.51-UR 4425

Product Description

The SANDVIK COROMANT 7861132 is a TCMT-style triangular turning insert in the CoroTurn 107 series, designed for external turning operations on CNC lathes and turning centers. The insert is manufactured from solid carbide with a CVD-applied multilayer coating consisting of Al2O3, TiN, and TiCN, corresponding to manufacturer grade 4425. This coating stack delivers wear resistance and thermal stability suited for continuous and light interrupted cuts. With a 3/8-inch (0.3750 inch) inscribed circle, a 0.4 mm (0.0156 inch) corner radius, and a 60-degree included angle, this insert fits standard TCMT toolholders and provides three usable cutting edges per insert. The neutral hand orientation and UR chip breaker geometry are matched to general steel and cast iron turning.

This insert is intended for medium-duty turning of steel and cast iron workpieces in production and job-shop environments. The UR chip breaker geometry is optimized for reliable chip control across a range of depths of cut and feed rates typical in finishing to semi-finishing passes. The grade 4425 with CVD coating is classified under ISO material group P (steel) as the primary application and group K (cast iron) as secondary. It is installed by licensed machinists and CNC operators in shops running TCMT-compatible toolholder systems within the CoroTurn 107 platform.

Key Features

• CVD multilayer coating: Al2O3, TiN, and TiCN for thermal and abrasion resistance
• Grade 4425 carbide substrate suited for steel (ISO P) and cast iron (ISO K) turning
• 60-degree triangular shape with 3 usable cutting edges per insert
• UR chip breaker geometry for controlled chip evacuation in finishing and semi-finishing
• Neutral hand orientation compatible with standard TCMT toolholder pockets
• Clamp and screw insert holding method for rigid, repeatable seating

Compatibility

Designed for use in TCMT-compatible toolholders within the CoroTurn 107 series. ISO code TCMT 16 T3 04-UR 4425. Industry standard number TCMT 16 T3 04-UR 4425. Manufacturers catalog number TCMT 3(2.5)1-UR. Compatible with insert size code 16T3 toolholder pockets accepting a 0.1732-inch hole diameter screw mount.

Installation Notes

Installation is performed by qualified machinists or CNC tooling technicians. Power down and lock out the machine spindle before seating or removing inserts. Use the correct torx or hex key torque driver as specified by the toolholder manufacturer for the clamping screw — do not overtighten. Inspect the toolholder pocket for wear or debris before seating a new insert to ensure proper contact and repeatability.