Kennametal 5591786 VBMT331MP KCM25B Carbide Turning Insert

Product Description

The KENNAMETAL 5591786 is a VBMT331MP turning insert in grade KCM25B, featuring a multilayer CVD coating system of TiCN, Al2O3, and TiOCN applied via MTCVD process. The insert is ground to a 35-degree diamond (rhombic) shape with a positive rake angle of 12 degrees, a 5-degree relief angle, and a honed cutting edge. It measures 16.61 mm (1.3076 inches) in length with a 3/8-inch inscribed circle diameter and a 1/64-inch corner radius. The screw-on holding method and neutral hand orientation suit a wide range of turning toolholders. Licensed machinists and CNC operators in production and job-shop environments are the primary installers.

This insert is designed for turning, facing, boring, back turning, and back boring operations. The MP chip breaker geometry is rated for roughing and medium machining applications. Primary workpiece materials include steel and stainless steel, with the KCM25B grade also suited for superalloys and titanium. Grade characteristics emphasize high toughness on steel (P) workpieces and moderate wear resistance with toughness on stainless steel (M) workpieces. It conforms to ANSI insert code VBMT331 and ISO insert code VBMT160404, making it interchangeable with other inserts meeting those standards.

Key Features

• Multilayer CVD coating: TiCN base, Al2O3 mid-layer, TiOCN outer layer for wear resistance on steel and stainless
• MP chip breaker geometry suited for roughing and medium machining depths
• 35-degree diamond insert shape with positive rake and positive side clearance for reduced cutting forces
• Honed cutting edge for improved edge stability in interrupted or variable-feed cuts
• Screw-on mount with 2 usable cutting edges for consistent repeatability at insert change
• Conforms to ANSI VBMT331 and ISO VBMT160404 standards for broad toolholder compatibility

Compatibility

Conforms to ANSI insert code VBMT331 and ISO insert code VBMT160404. Fits screw-on VBMT-style toolholders designed for 3/8-inch inscribed circle inserts with a 3/16-inch insert thickness and a 0.1732-inch hole diameter. Multi-use application includes turning, facing, boring, back turning, and back boring.

Installation Notes

Installation is performed by machinists or CNC setup technicians following standard insert-change procedures for screw-on toolholding systems. Power down or lock out the machine spindle before seating or removing the insert. Ensure the insert pocket and seating surface are clean and free of chips before torquing the clamping screw to the toolholder manufacturer's specification. Do not exceed the maximum depth of cut of 0.4354 inches for the given workpiece material and machine rigidity conditions.