Sumitomo 166REPJ Pcbn Turning Insert 1/4 Inch Ic 80 Diamond

Product Description

The SUMITOMO 166REPJ is a polycrystalline cubic boron nitride (PCBN) turning insert designed for precision machining of hardened steel and other difficult-to-cut ferrous materials. Coated with titanium nitride (TiN) via a PVD process, this insert offers enhanced surface hardness and wear resistance at the cutting edge. It features an 80-degree diamond insert shape with a 1/4-inch inscribed circle, a 1/64-inch corner radius, and a positive rake geometry. With two cutting edges and a screw-type holding method, it is suited for high-accuracy finishing and semi-finishing turning operations. Licensed machinists and CNC tooling specialists install this insert on indexable turning toolholders.

This insert is intended for turning operations on hardened steel workpieces in demanding production environments. The 2NC-CCGA insert style with clearance code C and tolerance code G makes it appropriate for applications requiring tight dimensional control. The chip breaker designation A and positive rake geometry help manage chip flow during finishing passes. Typical use cases include hard turning on CNC lathes where grinding is being replaced by single-point turning of materials with high hardness ratings. The insert conforms to ANSI and ISO 13399 standards, making it compatible with ISO-compliant tooling systems.

Key Features

• PCBN cutting material for machining hardened steel and difficult ferrous alloys
• TiN coating applied via PVD process for improved edge wear resistance
• 80-degree diamond insert shape with positive rake for reduced cutting forces
• 1/64-inch corner radius for fine surface finish requirements
• Two cutting edges per insert for extended tooling economy
• Screw-type insert holding method for secure, repeatable seating in the toolholder

Compatibility

Designed as an OEM-style replacement insert for indexable turning toolholders accepting 2NC-CCGA style PCBN inserts with a 1/4-inch inscribed circle. ISO code 2NC-CCGW060204 applies for cross-referencing compatible toolholder systems per ISO 13399.

Installation Notes

Installation should be performed by a qualified machinist or CNC tooling technician. Ensure the machine spindle is fully stopped and all energy sources are locked out before indexing or replacing inserts. Use the appropriate torx or hex key to secure the clamping screw to the toolholder manufacturer's specified procedure. Avoid touching the PCBN cutting edge directly, as edge chipping can result from improper handling.