Carmex 21-11.5NPTMT7 Carbide Thread Mill Insert Npt

Product Description

The CARMEX 21-11.5NPTMT7 is a carbide thread mill insert designed for cutting NPT (National Pipe Taper) threads at 11.5 teeth per inch. Manufactured from submicron carbide in grade MT7, this insert features a TiAlN coating for extended tool life in ferrous and non-ferrous materials. The conical geometry conforms to ANSI B1.20.1-1983 and supports both internal and external thread milling operations. Insert style is 21IE with an insert size code of 21 and a thickness of 0.185 inches (4.7 mm). It is installed in compatible thread mill toolholders and is suited for CNC machining centers performing pipe thread operations.

This insert is used in machine shops, maintenance facilities, and production environments where NPT pipe threads are required on internal bores or external workpiece diameters. Typical applications include thread milling of pipe fittings, manifolds, fluid system components, and hydraulic or pneumatic housings. The NPT conical thread form makes it appropriate for sealing applications in plumbing, HVAC, and industrial fluid transfer assemblies. The insert is catalogued under UNSPSC code 23291804 and is supplied individually, with a minimum order quantity of five units.

Key Features

• Submicron carbide substrate in manufacturer grade MT7 for wear resistance and edge stability
• TiAlN coating extends tool life in demanding cutting conditions
• Conical insert geometry conforms to ANSI B1.20.1-1983 NPT standard
• Cuts both internal and external NPT threads at 11.5 TPI
• Insert thickness of 0.185 inches (4.7 mm) for consistent seating in compatible toolholders
• Certified to CE, ISO 9001:2015, ISO 13485:2016, ISO 14001:2015, and ISO 45001 standards

Compatibility

Designed for use with compatible CARMEX 21-series thread mill toolholders that accept the 21IE insert style. Suitable for NPT thread milling at 11.5 TPI per ANSI B1.20.1-1983 on both internal and external thread forms.

Installation Notes

Thread mill inserts of this type are installed and indexed by a qualified machinist or toolroom technician. Power down and lock out the CNC machining center before changing or indexing inserts. Use the correct torx or insert-clamping screw specified by the toolholder manufacturer and do not substitute fasteners. Verify insert seating and clamping integrity before resuming cuts, and always confirm thread form and pitch against a calibrated NPT gauge after the first pass.