Kennametal 4050520 SNMG643RP KCU25 Carbide Turning Insert

Product Description

The KENNAMETAL 4050520 is a solid carbide turning insert in the SNMG643RP geometry, coated with AlTiN via a PVD process and graded KCU25. It is part of the KENLOC series and is designed for external and internal turning, facing, and boring operations on CNC and manual lathes. The square insert shape provides 8 cutting edges, and the RP chip breaker is optimized for roughing and medium machining. The KCU25 grade delivers moderate wear resistance combined with toughness, making it well suited to interrupted cuts and variable stock conditions. The 3/4-inch inscribed circle and 0.0469-inch corner radius define the cutting geometry.

This insert is intended for machining steel, stainless steel, cast iron, aluminum and non-ferrous materials, as well as superalloys and titanium. It carries ISO material codes P, M, K, N, and S, reflecting broad workpiece compatibility across production and job-shop environments. Typical applications include general turning, shoulder facing, and boring passes where moderate chip loads and reliable edge life are required. It is installed by machinists and CNC operators working in precision metalworking, aerospace, energy, and general manufacturing. The RP chip breaker geometry handles chip control across a range of feed rates common in roughing and semi-finish passes.

Key Features

• KCU25 AlTiN PVD coating provides moderate wear resistance and toughness across steel, stainless steel, cast iron, and non-ferrous workpieces
• Square insert shape (SNMG) delivers 8 usable cutting edges per insert
• RP chip breaker geometry engineered for roughing and medium machining applications
• Negative rake and negative side clearance support heavy interrupted cutting without edge chipping
• Compatible with clamp and pin holding methods for flexible toolholder use
• Chamfered and honed cutting edge preparation balances strength and sharpness

Compatibility

Designed as an OEM-style replacement insert conforming to ANSI designation SNMG643RP and ISO designation SNMG190612RP. Fits KENLOC-series and other SNMG-compatible toolholders accepting a 3/4-inch inscribed circle square insert with a 0.3125-inch hole diameter.

Installation Notes

Insert installation and indexing should be performed by a qualified machinist with the machine spindle fully stopped and all energy sources locked out per applicable machine safety procedures. Use the appropriate torque wrench and insert screw for the toolholder manufacturer's specified clamping torque to avoid seat damage. Inspect the toolholder pocket and clamping components for wear or debris before seating a new insert. Do not exceed the maximum depth of cut of 0.2498 inches as specified for this geometry.