Hertel 8850590 Turning Insert CNMG431BH HT115CR Cermet

Product Description

The HERTEL 8850590 is a cermet turning insert designed for precision external and internal turning operations on CNC and manual lathes. Manufactured to CNMG431 style geometry with an 80-degree diamond shape, this insert features an uncoated cermet substrate and a neutral hand orientation. It carries grade HT115CR and delivers a positive rake angle of 15 degrees, making it well suited for finishing and semi-finishing cuts on ferrous and non-ferrous materials. The inscribed circle measures 0.5 inches, insert length is 0.4724 inches (12 millimeters), and the corner radius is 0.0156 inches (1/64 inch). Installation uses a clamp and pin holding method. Experienced machinists and toolroom technicians are the primary users of this insert.

This insert is intended for turning centers and engine lathes where a CNMG-style pocket is present. The G chip breaker geometry and positive rake are suited to light-to-medium depth finishing passes. The cermet substrate without coating performs well on steel and cast iron at moderate-to-high cutting speeds where surface finish quality is a priority. It is sold individually per unit with a minimum order quantity of 10 pieces, making it appropriate for shop floor stocking or toolcrib replenishment.

Key Features

• Cermet uncoated substrate grade HT115CR for consistent finishing performance
• 80-degree diamond insert shape (CNMG style) with positive rake geometry
• Rake angle of 15 degrees with G-style chip breaker for controlled chip flow
• Corner radius of 0.0156 inches (1/64 inch) for tight tolerance surface finishing
• Clamp and pin holding method for secure seating in CNMG toolholders
• Neutral hand orientation fits both left- and right-hand turning applications

Compatibility

Designed for use in CNMG-style insert pockets on turning toolholders that accept a 0.5-inch inscribed circle, 3/16-inch thick insert with a 0.2030-inch hole diameter and clamp-and-pin retention.

Installation Notes

Installation is performed by qualified machinists or toolroom technicians. Power down and lock out the machine spindle before seating or indexing any insert. Verify the toolholder pocket is clean and free of debris before installing the insert, and confirm the clamp and pin are fully engaged before resuming cuts. Do not exceed the insert or toolholder manufacturer recommended depth of cut or feed rate for the grade in use.