Osg 1657507008 Spiral Flute Pipe Tap 1/4-18 Npt

Product Description

The OSG 1657507008 is a spiral flute pipe tap designed to cut 1/4-18 NPT internal threads in a wide range of materials. Built from high-speed steel with a V-coating finish, this tap features a 40-degree helix angle and three right-hand flutes that evacuate chips efficiently during the tapping operation. The overall length is 4 inches, with a thread length of 1.063 inches and a shank diameter of 0.563 inches. It is intended for use by machinists, pipefitters, and maintenance technicians who need to produce accurate NPT tapered pipe threads in production or repair applications.

This tap is suited for threading pipe fittings, manifolds, valve bodies, and mechanical assemblies where a sealed NPT connection is required. The spiral flute geometry makes it well suited for blind-hole applications, where the flute design pulls chips back out of the hole rather than pushing them forward. Compatible materials include carbon steel, alloy steel, stainless steel, cast iron, cast aluminum, titanium, and hardened steel, covering most ferrous and non-ferrous workpieces encountered in trade and industrial settings.

Key Features

• 1/4-18 NPT thread form for standard tapered pipe thread applications
• 40-degree right-hand helix angle promotes upward chip evacuation in blind holes
• High-speed steel construction provides hardness and wear resistance across listed material types
• V-coating finish reduces friction and extends tool life
• Three-flute design balances chip clearance with thread form stability
• No coolant-through design — suitable for hand or machine tapping with applied cutting fluid

Compatibility

Designed for tapping 1/4-18 NPT threads in carbon steel, alloy steel, stainless steel, cast iron, cast aluminum, titanium, and hardened steel workpieces. Part of OSG Series 16575.

Installation Notes

This tap should be installed in a tapping chuck or rigid holder on a drill press, CNC machining center, or used with a tap wrench for hand tapping. Always apply an appropriate cutting fluid for the workpiece material before and during the tapping operation. Power down and secure the workpiece fully before engaging the tap. Inspect the tap for chipping or wear before each use, as a damaged tap can seize or break in the hole.