Osg 1312605 Nptf Pipe Tap 1/8-27 4 Flute Hss Tin

Product Description

The OSG 1312605 is a standard pipe tap designed to cut 1/8-27 NPTF threads in metal workpieces. NPTF (National Pipe Taper Fuel) threads create a pressure-tight mechanical seal without requiring a separate sealant, making this tap a preferred choice in fluid and gas line applications. The tap is machined from high-speed steel and coated with titanium nitride (TiN) for improved wear resistance and extended tool life. With 4 flutes and a regular hook, it produces clean, accurate threads across a range of base materials. Overall length is 2.13 inches and thread length is 0.75 inches. Machinists, pipefitters, and HVAC technicians use this tool in production and maintenance tapping operations.

This tap is suited for threading ports and fittings in residential and light commercial applications where NPTF pipe connections are required. Typical uses include tapping manifolds, valve bodies, and pipe fittings in HVAC refrigerant circuits, plumbing assemblies, and pneumatic systems. The Series 118 designation places it within OSG's standard pipe tap line. Rated for use in carbon steel, cast iron, and aluminum, making it versatile across common trade materials.

Key Features

• 1/8-27 NPTF thread form for pressure-tight pipe connections without sealant
• High-speed steel construction for strength and heat resistance during tapping
• TiN coating reduces friction and extends cutting edge life
• 4-flute design with regular hook for controlled chip evacuation
• Compatible with carbon steel, cast iron, and aluminum workpieces
• Series 118 standard pipe tap geometry for consistent thread quality

Compatibility

Designed for tapping 1/8-27 NPTF threads in carbon steel, cast iron, and aluminum components. Fits standard tap holders and drive handles accepting a 0.4375-inch shank with a 0.328-inch square drive.

Installation Notes

This tap is installed by a machinist or pipefitter using a tap wrench, tapping head, or machine spindle sized for the shank diameter. Ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill size for 1/8-27 NPTF before beginning. Apply a suitable cutting fluid rated for the base material to reduce heat and prevent galling. Do not force the tap if resistance increases unexpectedly — back off to break chips and re-apply cutting fluid.