Hertel H59875906 TPGH322 HT630B Cermet Boring Insert

Product Description

The HERTEL H59875906 is a cermet uncoated boring insert designed for precision internal turning and boring operations on CNC lathes and boring bars. Built to TPGH322 geometry with a 60-degree triangular shape, this insert delivers consistent performance in finishing and semi-finishing applications where dimensional accuracy is critical. Key specifications include a 3/8-inch inscribed circle (0.3750 inches), a 1/8-inch thickness (0.1270 inches), and a 1/32-inch corner radius (0.0310 inches). The 11-degree relief angle reduces cutting forces and improves surface finish on harder workpiece materials. Cermet construction provides excellent wear resistance and edge retention, making it well-suited for high-speed, dry or near-dry cutting conditions. Installed by machinists and CNC operators in production and job-shop environments.

This insert is intended for boring, internal turning, and light-duty interrupted-cut applications where a cermet grade excels. The HT630B grade corresponds to an ISO C8 material grade, optimized for finishing passes on steel, cast iron, and some stainless alloys at elevated cutting speeds. It is a screw-held insert compatible with TPGH-style boring bar cartridges and holders that accept a triangular insert with the 322 size code. Typical use cases include tight-tolerance bore finishing in aerospace, automotive, and general metalworking production runs where surface finish and edge life are priorities.

Key Features

• Cermet uncoated construction for high wear resistance and sharp, stable cutting edges
• 60-degree triangular insert shape (TPGH style) with 11-degree relief angle to reduce cutting forces
• 1/32-inch corner radius (0.0310 inches) for controlled surface finish in finishing passes
• 3/8-inch inscribed circle for compatibility with standard TPGH322 boring bar holders
• Screw-held mounting method for secure, repeatable insert indexing
• HT630B grade (C8) suited for high-speed finishing on steel and cast iron

Compatibility

Designed as an OEM-style replacement insert for boring bars and cartridges that accept TPGH322 triangular screw-held inserts with a 3/8-inch inscribed circle.

Installation Notes

Installation is performed by machinists using the appropriate torx or hex key to seat the insert securely in a TPGH-compatible boring bar holder. Always power down and lock out the machine spindle before indexing or replacing inserts. Verify insert seating and torque the clamping screw to the holder manufacturer's specification before resuming cuts. Inspect the insert pocket and seating surface for chips or debris before each insert change to maintain runout accuracy.