Kennametal 5591789 Turning Insert VNMG331MP KCM25B

Product Description

The KENNAMETAL 5591789 is a solid carbide turning insert with a VNMG331MP geometry and KCM25B grade designation. It features a multilayer CVD coating — TiCN, Al2O3, and TiOCN — engineered to balance wear resistance and toughness on steel and stainless steel workpieces. The 35-degree diamond (rhombic) insert shape, combined with a chamfered and honed cutting edge, suits both roughing and medium machining operations. With a 3/8-inch inscribed circle, a 1/64-inch corner radius, and four usable cutting edges, this insert is a productive choice for CNC turning centers where insert life and predictable performance are priorities. Licensed machinists and CNC operators handling ferrous and difficult-to-machine materials are the primary users.

This insert is designed for turning, facing, boring, back turning, and back boring applications on steel, stainless steel, superalloys, and titanium. Its negative rake geometry and negative side clearance make it best suited for rigid setups and stable fixturing, typical in production turning environments. The MP chip breaker geometry supports chip control across a range of feed rates and depths of cut, reducing the risk of chip fouling on automated equipment. The insert is held using either a clamp or pin method, compatible with standard KENLOC toolholders from the same series.

Key Features

• VNMG331MP geometry with 35-degree diamond insert shape for low cutting forces in ferrous applications
• Multilayer CVD coating: TiCN, Al2O3, and TiOCN for wear resistance and toughness across steel and stainless steel grades
• MP chip breaker supports roughing and medium machining with effective chip control
• Four usable cutting edges per insert for extended tool economy
• Compatible with both clamp and pin holding methods in KENLOC-series toolholders
• Conforms to ANSI and ISO standards, ANSI code VNMG331, ISO code VNMG160404

Compatibility

Designed for use in KENLOC-series toolholders. Conforms to ANSI insert code VNMG331 and ISO insert code VNMG160404. Suitable for turning, facing, boring, back turning, and back boring of steel, stainless steel, superalloys, and titanium workpieces. Clamp or pin holding methods apply.

Installation Notes

Insert seating and torque should follow the toolholder manufacturer specifications for the KENLOC system. Always index or replace inserts with the spindle stopped and machine power locked out per shop LOTO procedures. Inspect the insert pocket and clamping hardware for wear or debris before seating a new insert. Machinists should verify depth-of-cut and feed parameters against the insert's rated maximum depth of cut before initiating a cut cycle.