Sandvik Coromant 5757986 Threading Insert 8 Tpi Api Round

Product Description

The SANDVIK COROMANT 5757986 is a solid carbide laydown threading insert engineered for right hand internal threading operations. Part of the CoroThread 266 series, it cuts API Round thread profiles at 8 threads per inch (TPI) with a 60-degree included angle. The insert features a dual-layer PVD coating of TiCrAlN and TiAlN for heat resistance and extended tool life in demanding threading applications. With a 3/8 inch inscribed circle and a thickness of 5/32 inch (0.1563 inch), it is sized for use in compatible CoroThread 266 toolholders. Installation and use are performed by machinists and tool-and-die professionals working in oil and gas or related industries requiring API Round thread standards.

This insert is suited for internal threading on tubular and coupling components that conform to API Round thread specifications. It is designed for use in CNC lathes and turning centers where precise thread form control is required. The single-tooth-per-side geometry and A chipbreaker style make it a direct fit for controlled-depth threading passes. Typical applications include machining pipe couplings, tool joints, and other oilfield components requiring certified thread profiles. Machinists working with 1125-grade solid carbide benefit from the balance of toughness and wear resistance this insert grade provides in interrupted or continuous internal threading cuts.

Key Features

• Solid carbide substrate with PVD-applied TiCrAlN and TiAlN dual coating for thermal and wear resistance
• Right hand internal API Round thread form at 8 TPI with 60-degree included angle
• CoroThread 266 series insert, style code 266RL-16RD01A080E, grade 1125
• 3/8 inch (9.53 mm) inscribed circle with 0.1732 inch (4.40 mm) hole diameter for secure clamping
• A-style chipbreaker optimized for single-point internal threading passes
• Insert size code 16 with thickness of 0.1563 inch (3.97 mm)

Compatibility

Designed for use with SANDVIK COROMANT CoroThread 266 series toolholders that accept size 16 right hand internal threading inserts. Specific toolholder compatibility should be confirmed against the CoroThread 266 system catalog using insert style code 266RL-16RD01A080E.

Installation Notes

This insert is installed and replaced by qualified machinists or CNC toolroom technicians. The machine spindle must be fully stopped and the turret or tool post must be de-energized before changing inserts. Use a calibrated torque wrench and the appropriate Torx or clamping screw specified by the toolholder manufacturer when seating the insert. Inspect the insert pocket for debris or damage before each installation to ensure proper seating and thread form accuracy.