Osg 1312601 Nptf Pipe Tap 1/8-27 4 Flute Hss

Product Description

The OSG 1312601 is a standard NPTF pipe tap designed to cut 1/8-27 tapered pipe threads in ferrous and non-ferrous materials. Built from high-speed steel with an oxide finish, it delivers consistent thread form across its 4-flute geometry and 0.75-inch thread length. The overall length is approximately 2.13 inches with a shank diameter of 0.4375 inches and a square drive size of 0.3280 inches. This tap is used by machinists, pipefitters, plumbers, and HVAC technicians when threading ports, fittings, and manifolds that require a dryseal pipe thread connection. The regular hook geometry suits most hand-tapping and machine-tapping operations on short-run production and maintenance work.

This tap is intended for threading 1/8-27 NPTF dryseal tapered pipe thread forms in a range of materials including carbon steel, cast iron, and aluminum. Typical applications include threading pipe ports in hydraulic and pneumatic components, HVAC refrigerant manifolds, plumbing fittings, and instrumentation connections where a pressure-tight dryseal thread is required without the need for sealant tape. The 4-flute design provides adequate chip clearance for these common shop and field materials.

Key Features

• NPTF dryseal tapered pipe thread form cuts pressure-tight connections without sealant
• High-speed steel construction handles carbon steel, cast iron, and aluminum
• Oxide finish provides mild lubricity and corrosion resistance during tapping operations
• 4-flute geometry offers balanced chip clearance and thread accuracy
• 0.4375-inch shank diameter fits standard tap holders and chucks
• Compact 2.13-inch overall length suits close-quarters threading applications

Compatibility

Designed for cutting 1/8-27 NPTF dryseal pipe threads in carbon steel, cast iron, and aluminum workpieces. Fits standard tap holders sized for a 0.4375-inch shank diameter with a 0.3280-inch square drive.

Installation Notes

This tap is installed by machinists or tradespeople using a standard tap wrench, T-handle, or machine tap holder rated for the shank size. Always use cutting fluid appropriate for the workpiece material to extend tool life and improve thread finish. Secure the workpiece firmly before tapping and back off periodically to break chips. Follow applicable shop safety practices and verify thread form with a NPTF plug gauge after tapping.