Sandvik Coromant 5857556 Threading Insert Npt 11.5 Tpi

Product Description

The SANDVIK COROMANT 5857556 is a solid carbide laydown threading insert designed for external NPT thread cutting at 11.5 threads per inch (TPI). Part of the CoroThread 266 series, it carries a TiCrAlN/TiN coating applied via PVD process, delivering wear resistance suited to demanding threading applications. The insert features a right-hand cutting orientation and a 60-degree included angle, consistent with standard NPT thread form. With a 3/8-inch inscribed circle and a thickness of 0.1563 inches (5/32 inches), this insert fits compatible CoroThread 266 toolholders. It is installed by machinists and toolroom professionals on CNC lathes and turning centers performing pipe thread operations.

This insert is intended for external NPT threading operations in production and job-shop environments. The CoroThread 266 platform is commonly used on CNC turning equipment where repeatability and consistent thread form are required. The F chipbreaker geometry supports controlled chip evacuation during threading passes. The PVD-applied TiCrAlN/TiN finish provides a combination of heat resistance and surface hardness suited to steel and alloy materials. Manufacturers catalog number for cross-reference is 266RG-16NT01F115E 1135.

Key Features

• Solid carbide substrate with PVD-applied TiCrAlN/TiN coating for extended tool life
• Right-hand external NPT thread form at 11.5 TPI with 60-degree included angle
• CoroThread 266 series insert with style code 266 and size code 16
• F chipbreaker geometry for controlled chip management during threading passes
• 3/8-inch (9.53 mm) inscribed circle; thickness of 0.1563 inches (3.97 mm)
• Single tooth per side configuration for precise thread profile control

Compatibility

Designed for use with compatible CoroThread 266 series toolholders accepting a 16-size laydown threading insert with a 0.1732-inch hole diameter. Refer to the manufacturers catalog number 266RG-16NT01F115E 1135 for toolholder matching.

Installation Notes

Insert seating and clamping should be performed with the machine fully powered down and the spindle locked. Use the correct torque wrench and insert key specified for the CoroThread 266 toolholder to avoid seat damage or insert cracking. Verify insert orientation for right-hand cutting before engaging the threading cycle. Follow applicable shop safety procedures and machine manufacturer guidelines when setting tool offsets for NPT thread form.