Walter 7091887 CNMG120404-FM5 WSM20S Turning Insert

Product Description

The WALTER 7091887 is a solid carbide turning insert designated ISO code CNMG120404-FM5 WSM20S, engineered for high-performance metal cutting in demanding materials. It carries a multilayer PVD coating of TiCN, Al2O3, and Al for heat resistance and extended tool life. The insert features an 80-degree diamond shape with a negative rake angle and a chamfered and honed cutting edge. With four usable cutting edges and the FM5 chip breaker geometry, it delivers reliable chip control across turning, facing, and boring operations. Licensed HVAC and machining tradespeople working with stainless steel, superalloys, and titanium will recognize this grade as purpose-built for ISO material groups M and S.

This insert is suited for CNC turning centers handling stainless steel and superalloy components where consistent chip evacuation and edge stability are critical. The FM5 geometry supports medium-depth roughing and semi-finishing passes. Secondary application covers carbon and alloy steel workpieces in ISO material group P, making this a versatile insert for shops running mixed material schedules. It is held by clamp and pin methods, fitting standard CNMG toolholders used in production and jobshop environments alike.

Key Features

• PVD-applied TiCN, Al2O3, and Al multilayer coating for thermal and abrasion resistance
• 80-degree diamond insert shape with negative rake for strong cutting edge support
• FM5 chip breaker geometry optimized for stainless steel, superalloys, and titanium
• Four cutting edges per insert for extended tool economy
• Chamfered and honed edge prep reduces micro-chipping on interrupted cuts
• Compatible with clamp and pin holding methods in standard CNMG toolholders
• Multi-use geometry supports turning, facing, and boring in a single insert grade

Compatibility

Designed for use in standard CNMG toolholders accepting a 0.5-inch inscribed circle insert. Primary workpiece materials are stainless steel, superalloys, and titanium (ISO groups M and S). Secondary workpiece material is steel (ISO group P). Industry standard number CNMG431-FM5 WSM20S applies for cross-reference purposes.

Installation Notes

Installation is performed by qualified machinists or toolroom technicians on CNC or manual turning equipment. Power down and lock out the machine spindle before seating or indexing the insert. Ensure the insert pocket and seating surfaces are clean and free of chips before clamping. Follow the toolholder manufacturer's clamping torque specifications and do not substitute clamping hardware between insert holding systems.