Sandvik Coromant 7861118 Turning Insert CCMT21.52-UM 4425

Product Description

The SANDVIK COROMANT 7861118 is a CCMT-style turning insert designed for external and internal turning operations on CNC lathes and turning centers. It carries the grade designation 4425 and features a CVD-applied multilayer coating of Al2O3, TiCN, and TiN over a solid carbide substrate. The insert geometry is neutral-hand with an 80-degree diamond shape, a 0.25-inch inscribed circle, a 0.0313-inch corner radius, and a 7-degree relief angle. The UM chip breaker geometry targets medium-range steel cutting conditions. This insert is installed by machinists and CNC operators in production and job-shop environments.

This insert is suited for turning steel and cast iron workpieces under the ISO P and K material classifications. The UM chip breaker is optimized for medium cutting depths and feeds on steel, making it a practical choice for general-purpose turning passes on both roughing and semi-finishing operations. The CoroTurn 107 series is designed for positive-rake toolholders that use either clamp or screw holding methods. Two cutting edges are available per insert, extending usable tool life before replacement.

Key Features

• CVD multilayer coating (Al2O3, TiCN, TiN) in grade 4425 for wear resistance on steel and cast iron
• 80-degree diamond insert shape with 7-degree relief angle (clearance code C)
• 0.0313-inch corner radius for a balance of edge strength and surface finish
• UM chip breaker geometry suited for medium-feed steel turning
• Neutral hand orientation compatible with standard positive-rake CoroTurn 107 toolholders
• Two usable cutting edges per insert

Compatibility

Designed for use in CoroTurn 107 series positive-rake toolholders that accept CCMT 06 02 08 inserts with clamp or screw holding. ISO code CCMT 06 02 08-UM 4425. Industry standard number CCMT 06 02 08-UM 4425. Compatible with ISO P (steel) and ISO K (cast iron) workpiece materials.

Installation Notes

Insert replacement and seating should be performed with the machine powered down and the spindle fully stopped. Verify the insert pocket is clean and free of debris before seating the new insert, as contamination under the insert can cause premature edge failure. Use the appropriate torx or hex key at the recommended seating force for the CoroTurn 107 clamping system. Follow the toolholder manufacturer guidelines for insert indexing sequence and clamping torque specifications.