Walter 7091885 CNMG120404-FM5 WMP20S Turning Insert Carbide

Product Description

The WALTER 7091885 is a CNMG-style indexable turning insert designed for precision metal removal in general turning, facing, and boring operations. It carries the ISO designation CNMG120404-FM5 WMP20S and is manufactured from solid carbide with a three-layer CVD coating of TiCN, Al2O3, and TiCN. The WMP20S grade targets steel and stainless steel as primary workpiece materials, with secondary capability in super-alloys and titanium. The FM5 chip breaker geometry promotes effective chip control across a broad range of cutting conditions. With four usable cutting edges, a neutral hand orientation, and a chamfered and honed cutting edge style, this insert is built for reliable, repeatable performance in production turning environments.

This insert is suited for lathe-based turning, facing, and boring applications on steel and stainless steel components in both job-shop and production settings. The negative rake geometry and 80-degree diamond insert shape provide a strong cutting edge with good resistance to mechanical shock. Material grades M20, P25, and S20 allow coverage across medium-duty roughing through finishing passes. The FM5 chip breaker is engineered to manage chip formation on ductile materials such as low-carbon and austenitic steels, where continuous chips are a common concern.

Key Features

• CVD three-layer coating: TiCN, Al2O3, TiCN for wear resistance and thermal protection
• WMP20S proprietary grade covering M20, P25, and S20 material classifications
• FM5 chip breaker geometry optimized for steel and stainless steel chip control
• Four cutting edges per insert with neutral hand orientation
• Chamfered and honed cutting edge style for edge stability and reduced chipping
• Compatible with clamp and pin insert holding methods
• Multi-use application: turning, facing, and boring from a single insert style

Compatibility

Designed for use in CNMG-style toolholders accepting a 0.5-inch inscribed circle insert with a 3/16-inch thickness and clamp or pin holding. Meets ANSI and ISO standards for CNMG120404 inserts. Industry standard number CNMG431-FM5 WMP20S applies for cross-reference purposes.

Installation Notes

Installation is performed by qualified machinists or CNC tooling technicians. The machine spindle must be stopped and all motion axes must be at rest before indexing or replacing inserts. Use the appropriate torque wrench and manufacturer-specified clamp screw when securing the insert to avoid seat distortion. Inspect the insert seat and clamp for wear or debris before seating a fresh cutting edge.