Osg 1252500 Spiral Flute Pipe Tap 3/4-14 Npt

Product Description

The OSG 1252500 is a spiral flute pipe tap designed for cutting 3/4-14 NPT internal threads in a range of metals. Built from high-speed steel with a bright finish, it features 5 right-hand flutes and a 15-degree helix angle that evacuates chips efficiently during the tapping operation. The bottoming chamfer allows threading closer to the bottom of a blind hole. At 3-1/4 inches overall length with a 0.9063-inch shank diameter, this tap is suited for use in drill presses, CNC machining centers, and manual tapping setups. Machinists and pipefitters install it when creating NPT-threaded ports and fittings in fabricated assemblies.

This tap is intended for tapping NPT pipe threads in materials including aluminum, carbon steel, cast iron, and hardened steel. The spiral flute design makes it well-suited for blind-hole applications where chip packing is a concern. It is part of the OSG S125 series and is a practical choice for job shops, maintenance facilities, and production environments requiring reliable NPT thread formation in a range of workpiece materials.

Key Features

• 3/4-14 NPT thread size with 14 threads per inch for standard pipe thread fitment
• 5 right-hand spiral flutes with 15-degree helix angle for upward chip evacuation
• Bottoming chamfer enables threading near the base of blind holes
• High-speed steel construction provides durability across multiple material types
• Bright finish with no coolant-through design; suitable for use with cutting fluid applied externally
• OSG S125 series - consistent geometry for repeatable thread quality

Compatibility

Designed for cutting 3/4-14 NPT internal threads in aluminum, carbon steel, cast iron, and hardened steel workpieces. Compatible with standard tap holders and chucks sized for a 0.9063-inch shank diameter.

Installation Notes

Installation is performed by qualified machinists or pipefitters using a drill press, tapping arm, or CNC machining center with appropriate tap holder. Ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill size for 3/4-14 NPT before beginning. Apply a suitable cutting fluid or tapping compound throughout the operation to extend tool life and improve thread quality. Never force a tap that has stopped turning - back it out to clear chips before continuing.