Hertel K015974AS25 Extension Pipe Tap 1/4-18 Nptf Hss Tin

Product Description

The HERTEL K015974AS25 is a 1/4-18 NPTF extension pipe tap ground from high speed steel and finished with a titanium nitride (TiN) coating. It is designed to cut tapered pipe threads in ferrous and non-ferrous materials where standard-length taps cannot reach. The 5-flute geometry with an interrupted thread design reduces torque, improves chip evacuation, and extends tool life in production and maintenance threading applications. With a 6-inch overall length and a 0.5625-inch shank diameter, this tap is suited for use in deep-bore or extended-reach setups. Licensed machinists, pipefitters, and maintenance mechanics are the primary users.

This tap is used wherever 1/4-18 NPTF tapered pipe threads are required in deep or obstructed bores that standard pipe taps cannot access. Typical applications include pipe fitting preparation in HVAC equipment, hydraulic manifolds, fluid power systems, and industrial plumbing assemblies. The extension length provides clearance in confined housings and deep-set port locations. The NPTF thread standard produces a dry-seal mechanical fit without relying solely on thread sealant, making it appropriate for pressure-bearing fluid and gas connections.

Key Features

• 1/4-18 NPTF tapered pipe thread profile for dry-seal pressure-bearing connections
• 5-flute interrupted thread design reduces cutting torque and improves chip control
• TiN coating increases surface hardness and wear resistance for extended tool life
• 6-inch overall length provides extended reach into deep bores and confined housings
• 0.5625-inch shank diameter with 0.4210-inch square drive for standard tap wrenches and holders
• High speed steel construction suitable for a broad range of ferrous and non-ferrous workpiece materials

Compatibility

Designed for threading 1/4-18 NPTF tapered pipe thread forms in any material compatible with high speed steel cutting tools. Fits standard tap wrenches, extension tap holders, and CNC rigid-tap tooling with a 0.5625-inch round shank and 0.4210-inch square drive.

Installation Notes

This tool is installed by licensed machinists, pipefitters, or maintenance mechanics using a calibrated tap wrench or machine spindle rated for the torque required by the workpiece material. Secure the workpiece before tapping and ensure the bore is drilled to the correct tap drill diameter for 1/4-18 NPTF before starting the tap. Apply cutting fluid appropriate to the workpiece material throughout the operation. Reverse the tap periodically to break chips and prevent tap breakage in blind-hole applications.