Hertel H59874081 Boring Insert TPCB221 Solid Carbide

Product Description

The HERTEL H59874081 is a solid carbide boring insert designed for precision internal turning and boring operations on CNC and manual lathes. Manufactured in the TPCB221 insert style with a triangular 60-degree included angle, this insert carries a TiN coating applied via PVD process, which improves wear resistance and extends tool life in ferrous and non-ferrous machining applications. The HP520B grade targets general-purpose and finishing cuts. Key geometry specs include a 1/64 inch (0.0150 inch) corner radius, a 1/4 inch (0.2500 inch) inscribed circle, and a thickness of 3/32 inch (0.0960 inch), with an 11-degree relief angle suited to boring head and cartridge toolholders.

This insert is used in boring bar and cartridge setups on manual lathes, CNC turning centers, and machining centers performing internal diameter work. The screw-clamping holding method makes it compatible with standard TPCB-style boring heads and cartridge holders. The triangular shape provides three usable cutting edges per insert, making it a practical choice for machine shops handling medium to high production volumes. Material grade C5 positions it for use on cast iron, steel, and similar workpiece materials under moderate to high cutting speeds.

Key Features

• Solid carbide construction with PVD TiN coating for extended wear resistance
• TPCB221 insert style with 60-degree triangle shape — three usable cutting edges per insert
• 1/4 inch inscribed circle and 3/32 inch thickness for compact boring bar and cartridge fitment
• 11-degree relief angle optimized for internal boring and finishing applications
• 1/64 inch corner radius for tight-tolerance surface finish requirements
• Screw-clamp holding method for positive, repeatable seating in TPCB-style toolholders

Compatibility

Designed for use in TPCB-style boring bars, cartridge holders, and boring heads that accept 221-size triangular carbide inserts with screw-clamp retention. Verify holder geometry and pocket specifications before ordering.

Installation Notes

Insert installation should be performed by a qualified machinist or tooling technician with the machine in a full stop, locked-out condition. Use the appropriate torx or hex key to seat the clamping screw to the toolholder manufacturer's specified torque. Inspect the insert pocket and clamping seat for chips or debris before seating a new insert, as contamination affects insert stability and surface finish. Rotate to a fresh cutting edge or replace the insert at first signs of chipping, built-up edge, or dimensional drift in the bored feature.