Kennametal 4109937 Grooving Insert NRD4125 KCU25 Carbide

Product Description

The KENNAMETAL 4109937 is a solid carbide grooving insert in the Top Notch series, designed for external grooving and turning operations on CNC lathes and manual turning centers. It carries a KCU25 manufacturer grade with a PVD-applied AlTiN coating that improves heat resistance and extends tool life in steel, stainless, and alloy machining applications. The insert features a 0.25 inch (6.35 mm) cutting width, a maximum depth of cut of 0.50 inch (12.70 mm), and a full radius corner profile with a 0.1252 inch (3.18 mm) corner radius. The clamp-style holding method provides rigid seating in compatible Top Notch toolholders. This insert is sold individually and typically specified by toolroom supervisors, CNC machinists, and tool crib personnel.

This insert is suited for production turning environments where consistent groove geometry and surface finish are required. The NRD style with right-hand orientation is used in standard OD grooving setups on lathes. The 55-degree included angle and full radius geometry make it effective for grooving profiles where blend radii matter. The KCU25 grade is positioned for interrupted cuts and general-purpose metal removal across a range of ferrous materials. Applicable depth of cut range runs from 0.30 inch to 1.00 inch (10.00 mm to 20.00 mm), covering a broad spectrum of groove depth requirements in job shop and production settings.

Key Features

• KCU25 solid carbide grade with PVD AlTiN coating for extended wear resistance
• 0.25 inch (6.35 mm) cutting width with full radius corner geometry
• Maximum depth of cut 0.50 inch (12.70 mm); effective range 0.30 inch to 1.00 inch
• Right-hand orientation, NRD insert style, clamp-style holding method
• 55-degree included angle suits standard OD grooving profiles
• Top Notch series for use with compatible KENNAMETAL Top Notch toolholders

Compatibility

Designed for use with KENNAMETAL Top Notch series toolholders accepting Insert Seat Size 4 and NRD-style inserts. Compatible toolholder reference: MSC/Manufacturer Number NRD4125R/L. No additional compatible model numbers were specified in the product data.

Installation Notes

Installation is performed by a qualified machinist or toolroom technician. Ensure the machine spindle is fully stopped and the lathe is in a locked-out, de-energized state before changing inserts. Seat the insert fully against the toolholder pocket and verify the clamp is torqued per the toolholder manufacturer specification before resuming cuts. Do not exceed the rated maximum depth of cut or feed rates for the KCU25 grade, as overloading a carbide insert can cause sudden fracture.