Hertel H59874719 Boring Insert TPCH220.5 HT630B Cermet

Product Description

The HERTEL H59874719 is a cermet uncoated boring insert designed for precision internal turning and boring operations on CNC and manual lathes. Built to TPCH style with a triangular 60-degree included angle, this insert features a 0.007-inch corner radius and a 1/4-inch inscribed circle (IC), making it well-suited for finishing and semi-finishing passes where tight tolerances and surface finish quality matter. At 3/32 inch thick with an 11-degree relief angle, the H59874719 provides adequate clearance to reduce rubbing while maintaining edge strength. The cermet substrate in the HT630B grade (C8 material grade) offers good wear resistance and thermal stability for dry or light-lubricated cutting conditions. It is installed using a screw-clamp holding method, consistent with standard TPCH-style toolholders.

This insert is intended for boring and internal turning applications in metalworking environments, including job shops, production machining facilities, and maintenance shops. The cermet uncoated construction makes it particularly effective on steel, cast iron, and some stainless alloys at moderate-to-high cutting speeds where a sharp, stable edge is required. Typical install scenarios include finish boring bores to close tolerances on CNC turning centers or manual boring bars equipped with compatible TPCH-style insert pockets. Machinists and toolroom technicians working on precision components will find this insert appropriate for achieving consistent surface finish results.

Key Features

• TPCH insert style with 60-degree triangular shape for versatile boring and turning geometry
• Cermet uncoated substrate in HT630B grade (C8) for wear resistance and edge sharpness
• 0.007-inch corner radius suitable for finishing and semi-finishing operations
• 1/4-inch inscribed circle (0.2500 inches) for compatibility with standard TPCH toolholders
• 11-degree relief angle reduces flank contact and rubbing during internal boring passes
• Screw-clamp insert holding method for positive, repeatable seating in the pocket

Compatibility

Designed as a direct-fit replacement for TPCH220.5-style boring insert pockets. Compatible with standard screw-clamp TPCH toolholders accepting a 1/4-inch IC triangular insert with 11-degree relief. Verify toolholder pocket geometry and screw thread before installation.

Installation Notes

Installation is performed by qualified machinists or toolroom technicians. Power down and lock out the machine spindle before changing inserts. Use the correct torque driver or hex key specified by the toolholder manufacturer to seat the clamping screw - do not overtighten, as cermet substrates are brittle and can crack under excessive clamping force. Inspect the insert pocket and locating surfaces for chips or debris before seating the new insert to ensure accurate positioning and full edge support.