Sandvik Coromant 5757979 Laydown Threading Insert Bspt 11 Tpi

Product Description

The SANDVIK COROMANT 5757979 is a solid carbide laydown threading insert designed for right-hand external BSPT thread cutting at 11 threads per inch. Part of the CoroThread 266 series, it carries a dual-layer PVD coating of TiCrAlN and TiAlN applied over the carbide substrate to extend edge life under demanding cutting conditions. The insert measures 3/8 inches inscribed circle and 5/32 inches thick, fitting standard 266-series threading toolholders. Grade 1125 provides a balanced combination of wear resistance and toughness suited to a wide range of workpiece materials. Licensed machinists and CNC operators install this insert in production threading and repair applications.

This insert is used in turning centers and CNC lathes where BSPT pipe thread profiles must be generated on external diameters. The 60-degree included angle and single tooth per side geometry produce a full-form British Standard Pipe Taper thread. It is appropriate for both production runs and low-volume threading work where consistent thread form and surface finish are required. The CoroThread 266 platform is a common choice in precision machining shops, pipe fitting manufacturers, and maintenance facilities that require traceable, repeatable thread geometry.

Key Features

• Solid carbide substrate with PVD TiCrAlN and TiAlN dual-layer coating for extended tool life
• Right-hand external BSPT thread profile at 11 TPI with a 60-degree included angle
• 3/8 inches (9.53 mm) inscribed circle for stable clamping in CoroThread 266 toolholders
• 5/32 inches (3.97 mm) thickness with a 0.1732 inch hole diameter for secure insert seating
• Grade 1125 carbide offers wear resistance suited to steel and stainless threading operations
• Insert Style 266 with Chipbreaker A geometry for controlled chip evacuation during threading passes

Compatibility

Designed for use in SANDVIK COROMANT CoroThread 266 series threading toolholders that accept size 16 laydown inserts. The manufacturers catalog number for this insert is 266RG-16PT01A110E 1125.

Installation Notes

Installation should be performed by a qualified machinist or CNC programmer with the machine spindle fully stopped and all energy sources locked out before insert exchange. Use a torque wrench calibrated to the toolholder manufacturer specification for the clamping screw to avoid seat distortion. Inspect the insert pocket and clamping components for debris or wear before seating the new insert. Verify thread form with a go/no-go gauge or optical comparator after the first threading pass.