Sandvik Coromant 5781940 Threading Insert 8-16 Tpi

Product Description

The SANDVIK COROMANT 5781940 is a laydown threading insert from the CoroThread 266 series, designed for external thread cutting on metalworking lathes and turning centers. Built from solid carbide with a PVD-applied TiCrAlN/TiN coating, this insert handles right-hand external 60-degree V threads across a range of 8 to 16 threads per inch (1.50 to 3.00 mm pitch). The 3/8-inch (9.53 mm) inscribed circle and 5/32-inch (0.1563 inch) thickness fit standard 266-series toolholders. A single cutting tooth per side and 0.0079-inch (0.20 mm) corner radius make it well suited for precision threading applications where thread form accuracy is critical. Licensed machinists and CNC turning technicians are the primary installers.

This insert is applied in external threading operations on a wide range of ferrous and non-ferrous workpiece materials in both production shop and job-shop environments. The TiCrAlN/TiN PVD coating supports improved wear resistance and tool life across varying cutting conditions. The A chipbreaker geometry is appropriate for general-purpose threading passes. Compatible toolholders accept the 266 insert style with a 4.40 mm (0.1732 inch) mounting hole diameter. This insert ships individually but carries a minimum order quantity of 10 units per purchase.

Key Features

• Solid carbide substrate with PVD TiCrAlN/TiN coating for wear resistance
• Right-hand external 60-degree V thread form, 8-16 TPI (1.50-3.00 mm pitch)
• 3/8-inch (9.53 mm) inscribed circle fits standard 266-series toolholders
• Corner radius of 0.0079 inches (0.20 mm) for precise thread root form
• A chipbreaker geometry suited for general external threading passes
• Manufacturer grade 1135 for defined cutting performance classification

Compatibility

Designed for use with SANDVIK COROMANT CoroThread 266 series toolholders that accept a 266-style insert with a 4.40 mm hole diameter and 3/8-inch inscribed circle. Refer to the manufacturers toolholder selection guide using insert style code 266 and size code 16 to confirm holder compatibility before installation.

Installation Notes

Installation is performed by qualified machinists or CNC turning technicians. Secure the insert in the designated 266-series pocketed toolholder using the correct clamping screw and torque procedure specified in the toolholder documentation. Ensure the machine spindle is fully stopped and the control is in a safe state before indexing or replacing inserts. Do not use damaged or chipped inserts, as degraded thread form can result in out-of-tolerance parts.