Kennametal 4033877 Threading Insert 18 Tpi Carbide Altin

Product Description

The KENNAMETAL 4033877 is a carbide threading insert designed for external thread cutting on UN-standard threads at 18 TPI. Manufactured in the Top Notch series under the NTC3R18E designation, this insert carries a KCU25 grade carbide substrate with a PVD-applied AlTiN finish for wear resistance at elevated cutting temperatures. The 60-degree included angle is standard for UN thread forms. At 0.195 inches thick with a corner radius of 0.0071 inches (0.18 mm), it is built for right-hand external threading applications where precision and edge integrity are critical. Installed by machinists and toolroom technicians on CNC lathes and threading machines.

This insert is suited for external threading operations on ferrous and non-ferrous workpieces in production machining environments. The AlTiN PVD coating supports dry or near-dry cutting conditions, making it a practical choice for high-speed threading passes where coolant use is limited or reduced. The Top Notch series insert style is indexed and replaceable within compatible Top Notch toolholders. Applications include threading of shafts, fittings, fasteners, and machined components requiring 18 TPI UN external thread profiles.

Key Features

• KCU25 carbide grade with PVD AlTiN coating for thermal and wear resistance
• 18 TPI external UN thread form with 60-degree included angle
• Right-hand cut orientation for standard lathe threading setups
• Corner radius of 0.0071 inches (0.18 mm) for accurate thread root geometry
• Top Notch series NTC insert style for indexed toolholder compatibility
• Insert size 3 with 0.195-inch thickness for rigid seating in the pocket

Compatibility

Designed for use in Top Notch series toolholders accepting NTC3 style inserts. Compatible with external threading applications requiring UN thread standard at 18 TPI, right-hand orientation.

Installation Notes

Threading inserts of this type are installed by qualified machinists or toolroom technicians. Ensure the machine spindle is fully stopped and the toolholder pocket is clean and free of debris before seating the insert. Torque the clamping screw according to the toolholder manufacturer specifications. Verify thread pitch and insert orientation against the workpiece print before initiating a threading pass.