Hertel H59873687 Boring Insert HC620B Solid Carbide

Product Description

The HERTEL H59873687 is a solid carbide boring insert designed for precision internal boring operations on CNC lathes and boring bars. Manufactured to the TDHH insert style in grade HC620B, this insert features a multilayer CVD coating sequence of TiN, TiC, TiCN, and TiN that improves wear resistance and extends tool life in steel and cast iron applications. The 60-degree triangular geometry delivers sharp, consistent cutting action, while the 0.007-inch corner radius suits fine to medium finishing passes. At 0.047 inches thick with a 5/32-inch inscribed circle, this is a compact insert suited to small-diameter boring work. Screw-clamped and left-hand oriented, it seats securely in compatible TDHH toolholders.

This insert is intended for use in metal-cutting environments where tight bore tolerances and surface finish are critical. The 15-degree relief angle reduces cutting forces and minimizes rubbing in close-tolerance bores. Typical applications include production turning on CNC lathes, boring mills, and machining centers running steel, alloy steel, or cast iron workpieces. The left-hand designation makes it suitable for climb-direction or back-boring setups where a right-hand insert would not perform correctly. Machinists and tool-crib personnel working in job shops, production facilities, or maintenance machining operations will find this insert a direct fit for TDHH-style boring systems.

Key Features

• Solid carbide substrate, material grade C7, for rigidity and wear resistance in ferrous materials
• Multilayer CVD coating: TiN, TiC, TiCN, TiN for extended tool life
• 60-degree triangular insert shape with 0.007-inch corner radius for finishing and medium-stock removal
• 15-degree relief angle reduces cutting forces in tight-bore applications
• Left-hand cutting orientation for back-boring or climb-direction setups
• Screw-holding method provides secure, repeatable insert indexing

Compatibility

Designed as a direct replacement for applications specifying TDHH-style boring inserts with manufacturer catalog number TDHH12807505L and HC620B grade.

Installation Notes

Installation should be performed by a qualified machinist or tooling specialist. Power down and lock out the machine spindle before indexing or replacing inserts. Use the correct torque wrench and manufacturer-specified insert screws to seat the insert without cracking the carbide substrate. Inspect the toolholder pocket and clamping screw for wear or damage before seating a new insert.