Kennametal 5455238 Spiral Point Tap 4-40 Unc Hss-e

Product Description

The KENNAMETAL 5455238 is a spiral point tap designed for right-hand through-hole threading in 4-40 UNC applications. Built from High-Speed Steel-E (HSS-E) and finished with a tri-coating of TiN, CrC, and C, this tap delivers hard-material performance in stainless steel and non-ferrous metal workpieces. The plug chamfer provides controlled thread lead-in, while the 2-flute geometry channels chips forward through the hole during cutting. At 1.875 inches overall length with a 0.510-inch thread length, it fits standard tapping chucks and CNC tap holders sized for small-diameter threading work. It carries an H2 thread limit for 2B and 3B class-of-fit tolerances.

This tap is suited for production and maintenance threading operations where small-diameter, fine-pitch threads are required in through-hole configurations. It is built for stainless steel and non-ferrous metals, making it a practical choice for precision machined components, fastener-thread preparation, and tooling fixtures. The Series T820 designation places it in a product family engineered for consistent performance on CNC machining centers and manual drill presses. Licensed machinists and tool-and-die technicians are the primary users of this tap size.

Key Features

• Spiral point geometry pushes chips forward through the hole, reducing clogging in through-hole applications
• HSS-E base material provides increased toughness and wear resistance compared to standard HSS
• Tri-coating of TiN, CrC, and C improves surface hardness and lubricity for extended tool life
• Plug chamfer (3-5 thread lead) for smooth thread entry and reduced starting torque
• H2 thread limit ensures compatibility with 2B and 3B class-of-fit thread gauging requirements
• Right-hand cut with 40 threads per inch at 0.025-inch pitch for 4-40 UNC standard

Compatibility

Designed for through-hole threading of 4-40 UNC threads in stainless steel and non-ferrous metal workpieces. Fits standard tapping chucks and holders accepting a 0.141-inch shank diameter.

Installation Notes

This tap is installed and operated by machinists or tool-and-die technicians using a tapping chuck, CNC rigid tap holder, or manual tap wrench. Always ensure the workpiece is securely fixtured and a suitable cutting fluid is applied, particularly when tapping stainless steel. Confirm the through-hole is drilled to the correct tap drill size for 4-40 UNC before beginning the threading operation. Do not reverse-drive a broken tap without appropriate extraction tooling.