Sumitomo 16JRCUM Turning Insert NUCNMA430.5 BN2000 Pcbn

Product Description

The SUMITOMO 16JRCUM is a polycrystalline cubic boron nitride (PCBN) turning insert designed for precision single-point turning on CNC and manual lathes. Manufactured to ANSI and ISO 13399 standards under ANSI code NUCNMA430.5 and ISO code NU-CNMA120402, this insert features an 80-degree diamond shape with a neutral hand orientation and a negative rake geometry. The BN2000 grade designation indicates an uncoated PCBN substrate engineered to maintain edge integrity at elevated cutting temperatures. With a corner radius of 0.0078 inches and a maximum depth of cut of 0.0150 inches, it is suited for finishing and semi-finishing operations requiring tight tolerances and fine surface finishes. Machinists, CNC operators, and tooling specialists install this type of insert in appropriate CNMA-style toolholders.

This insert is intended for use on hard and difficult-to-machine workpiece materials including cast iron, hardened steels, and superalloys. The PCBN cutting material resists abrasive wear and thermal softening, making it appropriate for high-speed finishing passes where carbide tooling loses edge life prematurely. Typical applications include hard turning on hardened bearing races, brake rotors, camshafts, and similar components where conventional abrasive grinding can be replaced with single-point turning. It is held in the toolholder by a clamp and pin method, common in CNMA-style insert seating configurations.

Key Features

• PCBN cutting material for hard turning of cast iron, hardened steels, and superalloys
• BN2000 uncoated grade optimized for abrasion resistance at elevated temperatures
• 80-degree diamond insert shape (Shape Code C) for rigid, stable cutting geometry
• Negative rake, zero-degree relief angle (Clearance Code N, Tolerance Code M)
• Clamp and pin holding method compatible with standard CNMA toolholder seats
• Meets ANSI and ISO 13399 standards for consistent interchangeable tooling

Compatibility

Designed as an OEM-style replacement turning insert for CNMA-series toolholders accepting a 1/2-inch inscribed circle, 3/16-inch thick diamond-shaped insert with a clamp and pin holding method.

Installation Notes

Installation should be performed by a qualified machinist or CNC tooling technician. Power down and lock out the machine before seating or removing inserts. Ensure the toolholder pocket and clamp are clean and free of chips before seating the insert, as debris under the insert will cause premature edge failure or dimensional inaccuracy. Do not exceed the maximum depth of cut specified for this insert geometry, and verify that the toolholder style and seating pocket match the CNMA insert configuration before clamping.