Hertel H59874537 Boring Insert TPCG221 HC620B Solid Carbide

Product Description

The HERTEL H59874537 is a solid carbide boring insert designed for precision internal turning and boring operations on CNC and manual lathes. Manufactured to TPCG221 insert geometry, it features a 60-degree triangular shape with an 11-degree relief angle and a 1/64 inch (0.0310 inch) corner radius. The HC620B grade substrate is processed via CVD coating with a multilayer TiN, TiC, TiCN, TiN finish, placing it in the C7 material grade range — suited for finishing and semi-finishing cuts in steel and cast iron. Machinists and toolroom technicians select this insert for boring bars requiring screw-held TPCG-style tooling with consistent edge geometry.

This insert is used in boring operations on CNC machining centers and manual lathes across light manufacturing, job shop, and production environments. The right-hand configuration makes it compatible with standard right-hand boring bar bodies that accept TPCG221 indexable inserts. It is well suited for applications requiring tight tolerances on internal diameters, where controlled corner geometry and a reliable multilayer CVD coating reduce built-up edge and extend tool life between index changes.

Key Features

• Solid carbide substrate with CVD-applied multilayer TiN, TiC, TiCN, TiN coating for wear resistance
• TPCG221 insert style — 60-degree triangle with 11-degree relief angle
• 1/4 inch inscribed circle (0.2500 inch) and 3/32 inch thickness (0.0960 inch)
• 1/64 inch corner radius (0.0310 inch) for semi-finish to finish boring cuts
• Screw-held mounting method for positive insert location in boring bar pockets
• Right-hand cutting configuration; HC620B grade rated C7 material grade

Compatibility

Designed as a direct-fit replacement for boring bar bodies accepting TPCG221-style screw-held indexable inserts with a 1/4 inch inscribed circle.

Installation Notes

Installation is performed by qualified machinists or toolroom technicians. Before indexing or replacing inserts, ensure the machine spindle is fully stopped and locked out per facility lockout/tagout procedures. Seat the insert fully into the pocket and torque the clamping screw to the boring bar manufacturer's specified value using the correct Torx or hex key — do not overtighten, as this can fracture the carbide. Inspect the insert pocket for chips or debris before seating a new edge.