Hertel H59873679 Boring Insert TDHH1.280.75.0.5 HP520B

Product Description

The HERTEL H59873679 is a solid carbide boring insert designed for precision metal-cutting operations on CNC and manual boring equipment. Manufactured to the TDHH insert style in grade HP520B, this insert features a triangular geometry with a 60-degree included angle and a 15-degree relief angle. The TiN coating is applied via PVD process, improving surface hardness and wear resistance for extended tool life in ferrous and non-ferrous materials. With a corner radius of 0.007 inches and an inscribed circle of 0.160 inches, it is suited for fine-bore finishing and semi-finishing passes where dimensional accuracy is critical. Installation requires a screw-type insert holding method on a left-hand toolholder.

This insert is intended for use in boring bars and toolholders that accept TDHH-style triangular inserts with screw clamping. It is appropriate for shop floor and production machining environments handling steel, cast iron, and similar materials graded for C5 carbide application. The left-hand designation means it is matched to left-hand boring bar configurations. Machinists and tooling specialists working in job shops, production facilities, or maintenance machining operations will find this insert suitable for internal diameter boring on lathes and boring mills.

Key Features

• Solid carbide construction in material grade C5 for rigidity and wear resistance
• TiN coating applied by PVD process for improved hardness and reduced friction
• Triangular 60-degree geometry with 15-degree relief angle for clean chip clearance
• Corner radius of 0.007 inches for precise surface finish control
• Screw-type insert holding method ensures secure seating in compatible toolholders
• Left-hand insert orientation for use with left-hand boring bar configurations

Compatibility

Designed as a direct-fit replacement for TDHH-style screw-clamp boring toolholders accepting a triangular insert with a 5/32-inch inscribed circle. Compatible toolholder catalog reference is TDHH12807505L per manufacturer data.

Installation Notes

Insert replacement should be performed by a qualified machinist or tooling technician with the machine powered down and the spindle locked. Use the appropriate torque wrench and insert screw driver to seat the insert without over-torquing the clamping screw, which can fracture the carbide body. Inspect the insert pocket and clamping screw for wear or damage before installing a new insert. Verify left-hand toolholder orientation before seating this insert to avoid improper cutting geometry.