Hertel 8852030 Turning Insert CPMH2.51.51 HT115CR Cermet

Product Description

The HERTEL 8852030 is a cermet turning insert in the CPMH style, designed for precision external turning operations on CNC and manual lathes. Manufactured to the CPMH2.51.51 designation with grade HT115CR, this insert features an 80-degree diamond shape with a positive rake geometry and a 5/16-inch (0.3125 inch) inscribed circle. The uncoated cermet substrate delivers consistent edge wear resistance and surface finish quality at moderate-to-high cutting speeds. With a corner radius of 1/64 inch (0.0156 inch), it is suited for finishing and semi-finishing passes where tight dimensional tolerances and low surface roughness are required. Machinists and CNC operators in production and job-shop environments install and index this insert as part of standard toolholder changeout procedures.

This insert is intended for turning applications on materials where cermet grades perform well, including carbon steels and alloy steels run at elevated speeds with light-to-medium depths of cut. The CPMH screw-on holding method and neutral hand orientation make it compatible with a range of standard CPMH-style toolholders used in both vertical and horizontal turning setups. It is appropriate for applications demanding close tolerances and consistent surface finish across production runs.

Key Features

• Cermet, uncoated substrate for sharp, stable cutting edges and consistent finish
• 80-degree diamond insert shape (Shape Code C) for versatile turning and facing
• Positive rake geometry reduces cutting forces and heat generation
• 1/64-inch corner radius (0.0156 inch) suited for finishing and semi-finishing passes
• Screw-on (Hole) holding method for secure, repeatable indexing
• Chip breaker style H integrated into insert geometry

Compatibility

Designed as an OEM-style replacement or direct-fit insert for standard CPMH-style turning toolholders accepting a 5/16-inch inscribed circle, 80-degree diamond insert with screw-on mounting.

Installation Notes

Turning insert installation and indexing should be performed by a qualified machinist or CNC tooling technician. Power down and lock out the machine spindle before accessing the toolholder. Use the appropriate torx or hex key to secure the clamping screw to the toolholder manufacturer's specified method — do not overtighten, as cermet substrates are brittle and susceptible to fracture under excessive clamping force. Inspect the insert seat and clamping screw for debris or damage before seating each new insert.