Sandvik Coromant 5757693 Threading Insert Un 18 Tpi

Product Description

The SANDVIK COROMANT 5757693 is a solid carbide laydown threading insert engineered for left-hand external UN thread cutting at 18 threads per inch. It carries a dual-layer PVD coating of TiCrAlN and TiAlN, which provides elevated heat resistance and wear protection during threading operations. With a 3/8 inch inscribed circle and a 60-degree included angle, this insert fits standard CoroThread 266 toolholders and is designed for precision thread profiles on metalworking lathes. It suits shops and toolrooms where consistent thread form and tool life are priorities in CNC turning operations.

This insert is intended for external UN threading applications on metalworking lathes and turning centers. The left-hand orientation serves specific spindle direction and workpiece setups that require reverse-hand cutting. With an 18 TPI specification, it covers common fastener and fitting thread pitches found in general machining, toolroom, and production environments. Licensed machinists and CNC turning specialists are the primary installers and users of this insert type.

Key Features

• Solid carbide substrate for rigidity and wear resistance in threading applications
• PVD-applied TiCrAlN and TiAlN dual-layer coating for thermal and abrasion resistance
• Left-hand, external UN thread geometry at 18 TPI with a 60-degree included angle
• 3/8 inch (9.53 mm) inscribed circle compatible with CoroThread 266 series toolholders
• Single tooth per side design for controlled thread form accuracy
• Chipbreaker style A for managed chip flow during threading cuts

Compatibility

Designed for use with SANDVIK COROMANT CoroThread 266 series toolholders accepting a 16-size insert with a 3/8 inch inscribed circle. Also referenced under manufacturers catalog number 266LG-16UN01A180M 1125.

Installation Notes

Insert changes should be performed by a qualified machinist with the machine spindle stopped and all motion axes at rest. Use the appropriate insert seating tool or torque wrench per the toolholder manufacturer specifications to secure the insert without over-torquing the clamp screw. Verify insert orientation for left-hand cutting direction before resuming operation. Inspect the insert pocket and seating surface for chips or debris before seating a replacement insert.