Sandvik Coromant 5857572 Threading Insert 24 Tpi Un

Product Description

The SANDVIK COROMANT 5857572 is a laydown threading insert designed for external UN thread cutting on CNC lathes and turning centers. Part of the CoroThread 266 series, it is manufactured from solid carbide with a PVD-applied TiCrAlN/TiN coating for wear resistance and tool life in steel and alloy threading operations. This insert cuts right-hand external threads at 24 threads per inch (TPI) with a 60-degree included angle. The 3/8-inch inscribed circle and 0.1563-inch thickness conform to standard indexable toolholder seats used across production and job-shop turning environments. Licensed machinists, CNC operators, and toolroom technicians are the primary users.

This insert is suited for external UN thread forms on ferrous and alloy workpieces in both production and repair turning applications. The A-style chipbreaker geometry promotes chip control during threading passes. With a 3/8-inch (9.53 mm) inscribed circle and a 0.1732-inch hole diameter, the insert seats into standard 266-series CoroThread toolholders. It is applicable in medium-to-fine threading work where dimensional consistency and surface finish on thread flanks are critical.

Key Features

• Solid carbide substrate with PVD TiCrAlN/TiN coating for extended wear life in threading operations
• Cuts right-hand external UN threads at 24 TPI with a 60-degree included angle
• A-style chipbreaker geometry for controlled chip evacuation during threading passes
• 3/8-inch inscribed circle and 0.1563-inch thickness for compatibility with standard 266-series seats
• Insert style 266, size code 16 - indexes into CoroThread 266 toolholders
• Single tooth per side design for predictable thread profile tracking

Compatibility

Designed for use in SANDVIK COROMANT CoroThread 266 series toolholders that accept a size-16 laydown threading insert with a 3/8-inch inscribed circle. Confirm toolholder seat and clamping style before ordering.

Installation Notes

Installation should be performed by a qualified machinist or CNC toolroom technician with the machine in a locked-out, zero-energy state before any insert indexing or replacement. Seat the insert fully against the pocket locating surfaces and torque the clamping screw per the toolholder manufacturer specification. Inspect the insert seat for chips or debris before seating to avoid insert rocking and thread-form error. Handle solid carbide inserts with care - carbide is brittle and can chip if dropped or impacted.