Sandvik Coromant 5857615 Laydown Threading Insert 20 Tpi

Product Description

The SANDVIK COROMANT 5857615 is a solid carbide laydown threading insert engineered for internal UN thread cutting operations. Carrying the manufacturer grade 1135 and finished with a PVD-applied TiCrAlN/TiN dual coating, this insert is built for precision threading in ferrous and hardened materials. It operates on a right-hand cutting orientation with a 60-degree included angle and a single tooth per side, producing clean, accurate thread forms at 20 threads per inch. At 0.1563 inches thick with a 3/8-inch inscribed circle, it seats securely in compatible 266-series toolholders. Licensed machinists and CNC tooling technicians install this insert in production turning and threading operations where consistent thread quality is required.

This insert belongs to the CoroThread 266 series and is designed for internal UN threading applications. The 266RL style designation indicates a right-hand, laydown geometry suited to longitudinal internal threading passes on CNC lathes and turning centers. With a chipbreaker designation of A and a 20 TPI configuration, it is suited to threading operations in typical UN fastener and fitting thread standards found across general machining, aerospace, and industrial production environments. The insert style code 266 combined with size code 16 determines compatible toolholder selection.

Key Features

• Solid carbide substrate with PVD TiCrAlN/TiN coating for wear resistance and edge stability
• Right-hand internal UN thread geometry at 20 TPI with 60-degree included angle
• CoroThread 266 series insert style 266RL, size code 16
• 3/8-inch inscribed circle (9.53 mm) with 0.1563-inch thickness (3.97 mm)
• Single tooth per side for controlled thread form engagement
• Chipbreaker style A for chip management in internal threading passes

Compatibility

Designed for use with SANDVIK COROMANT CoroThread 266 series toolholders accepting size code 16 laydown inserts. Manufacturer catalog reference 266RL-16UN01A200M 1135. Confirm toolholder bore and insert seat geometry before installation.

Installation Notes

This insert is installed and replaced by qualified machinists or CNC tooling technicians. Power down and lock out the machine spindle before changing inserts. Use the correct torx or hex key to the toolholder manufacturer's specified fastener procedure, and inspect the insert seat and clamping screw for debris or wear before seating the new insert. Do not exceed the recommended depth of cut or feed rate for the grade and coating specified for this insert.