Sandvik Coromant 5857540 Threading Insert Style 266

Product Description

The SANDVIK COROMANT 5857540 is a solid carbide threading insert designed for external thread cutting operations in metal machining applications. Built to the CoroThread 266 series standard, this insert features a 60-degree partial profile thread form and a left-hand cutting orientation. The PVD-coated Grade 1135 carbide substrate provides wear resistance and edge integrity across a thread pitch range of 1.50 to 3.00 mm (8 to 16 TPI). At 3.97 mm thick and with a 0.20 mm corner radius, the insert is sized for consistent, repeatable thread profiles on external workpiece surfaces. Licensed machinists and CNC turning specialists are the primary installers of this tooling.

This threading insert is suited for external threading operations on CNC lathes and turning centers in both production and job-shop environments. The CoroThread 266 series is used in applications requiring consistent partial profile 60-degree thread geometry, including general-purpose metric and unified thread cutting. The left-hand insert orientation accommodates specific spindle direction and thread handedness requirements. It is applicable in aerospace, automotive, oil and gas, and general industrial machining where controlled thread form accuracy is essential.

Key Features

• Solid carbide construction with PVD coating for extended tool life and edge sharpness
• Grade 1135 substrate optimized for threading operations on a range of workpiece materials
• 60-degree partial profile thread form covering 1.50 to 3.00 mm pitch (8 to 16 TPI)
• Left-hand cutting orientation for reverse-spindle or left-hand thread applications
• 0.20 mm (0.0079 inch) corner radius for controlled thread root geometry
• ISO code 266LG16VM01A002M1135 for precise toolholder compatibility identification

Compatibility

Designed for use with CoroThread 266 series toolholders that accept Size 16 inserts with Style 266 geometry, as specified by the ISO code 266LG16VM01A002M1135.

Installation Notes

Threading inserts of this type are installed and indexed by qualified machinists or CNC tooling technicians. Power down and lock out the machine spindle before seating or replacing inserts. Use the correct torx or clamping key specified for the CoroThread 266 toolholder to achieve proper seating torque without over-driving the clamping screw. Inspect the insert pocket and clamping mechanism for wear or debris before each insert change to ensure accurate positioning and repeatable thread quality.