Kennametal 5591779 CNMG431MP KCM25B Turning Insert

Product Description

The KENNAMETAL 5591779 is a CNMG431MP indexable turning insert in grade KCM25B, featuring a multilayer CVD coating of TiCN, Al2O3, and TiOCN applied by MTCVD process. The insert is shaped as an 80-degree diamond (rhombic) with a neutral hand orientation and negative rake and side clearance geometry. It measures 12.9 mm (0.5077 inches) in length with a 0.5-inch inscribed circle, 3/16-inch thickness, and a 1/64-inch corner radius. Designed for CNC turning applications, this insert is installed by machinists and toolroom technicians on lathes and turning centers targeting steel, stainless steel, and superalloy workpiece materials.

The 5591779 is part of KENNAMETAL's KENLOC series and is suited for roughing and medium machining operations. Its KCM25B grade delivers high toughness on steel (P-class) and moderate wear resistance with toughness on stainless steel (M-class), making it a practical choice for interrupted and continuous cuts in job-shop and production environments. It supports turning, facing, and boring operations from a single insert, reducing the number of tool changes required during a job.

Key Features

• Multilayer CVD coating (TiCN / Al2O3 / TiOCN) for wear resistance across steel and stainless steel applications
• 80-degree diamond insert shape (ANSI CNMG431 / ISO CNMG120404) with 4 usable cutting edges
• KCM25B grade rated for high toughness on steel and moderate wear resistance on stainless steel and superalloys
• MP chip breaker geometry supports both roughing and medium machining chip control
• Chamfered and honed cutting edge style for edge stability under heavy or interrupted cuts
• Compatible with clamp and pin insert-holding methods; fits standard KENLOC toolholders

Compatibility

Designed for use in KENLOC series toolholders accepting CNMG431 (ISO CNMG120404) inserts with clamp or pin retention. Primary workpiece materials are steel (P), stainless steel (M), and superalloys and titanium. Suitable for turning, facing, and boring operations.

Installation Notes

Installation is performed by a machinist or toolroom technician. Power down and lock out the machine spindle before seating or indexing the insert. Verify the insert pocket and seating surface are clean and free of chips before clamping. Follow the toolholder manufacturer's clamping torque specifications and confirm the insert is fully seated before resuming cuts.