Hertel H59875831 Boring Insert TPGH321HM1 Cermet Triangle

Product Description

The HERTEL H59875831 is a cermet uncoated boring insert designed for precision internal turning and boring operations on CNC and manual lathes. Manufactured in a TPGH style with a 60-degree triangular shape, this insert carries the HT630B material grade and C8 carbide grade classification. It features a 0.021-inch corner radius for controlled surface finish and a 0.127-inch thickness for rigidity under moderate feed conditions. The 11-degree relief angle reduces cutting edge friction and promotes clean chip evacuation. Licensed machinists and toolroom professionals use this insert for finish and semi-finish boring passes where dimensional accuracy is critical.

This insert is suited for internal diameter boring applications in job shops, production machining environments, and maintenance toolrooms. The cermet substrate performs well in finish turning of steel and cast iron at higher surface speeds where uncoated carbide grades may lack wear resistance. The HM1 chipbreaker geometry is intended for light-to-moderate chip control in precision boring applications. The insert is sold individually but carries a minimum order quantity of 10 units per order.

Key Features

• TPGH insert style with 60-degree triangular geometry for versatile boring tool holder compatibility
• Cermet uncoated substrate in HT630B grade, suited for finish and semi-finish boring of steel and cast iron
• 0.021-inch corner radius for controlled surface finish on bored diameters
• 3/8-inch inscribed circle (0.3750 inches) for standard TPGH toolholder seating
• 11-degree relief angle reduces flank friction and promotes clean chip flow
• HM1 chipbreaker geometry for light-to-moderate chip control

Compatibility

Designed for use in TPGH-style boring bar and insert toolholders that accept a 3/8-inch inscribed circle triangular insert. Confirm toolholder pocket specifications before installation.

Installation Notes

Insert seating and clamping should be performed by a qualified machinist following the toolholder manufacturer's torque and clamping specifications. Ensure the machine spindle is fully stopped and locked out before changing inserts. Inspect the toolholder pocket for chips, debris, or wear before seating the new insert. Do not exceed the recommended depth of cut or feed rate range for cermet-grade inserts, as cermet substrates are more brittle than coated carbide and are not suited for interrupted cuts or heavy roughing passes.