Accupro T1620442B Spiral Point Tap 5/16-18 Plug 2B Hss

Product Description

The ACCUPRO T1620442B is a spiral point tap designed for cutting 5/16-18 UNC threads in through-hole applications. Manufactured from 3% vanadium high-speed steel and finished with an oxide coating, this tap offers improved lubrication retention and resistance to galling during the threading process. It features a plug chamfer for guided thread entry and is ground to a 2B class of fit, which meets standard tolerance requirements for general fastener applications. With 3 flutes and a right-hand thread direction, it is suited for use in CNC machines, manual drill presses, and tapping arms where chip evacuation through the hole is preferred. The overall length is 2.7188 inches with a 22 mm thread length.

This tap is intended for threading stainless steel and other ferrous materials in production and maintenance environments. The spiral point geometry pushes chips forward ahead of the tap, making it well suited for through-hole tapping where chip buildup in the flutes is a concern. It is commonly used by machinists, tool and die makers, and maintenance technicians working with 5/16-18 fastener assemblies in industrial and commercial settings.

Key Features

• 5/16-18 UNC thread size with right-hand thread direction
• Plug chamfer provides gradual thread engagement for reliable starts
• 3% vanadium high-speed steel construction for extended tool life in stainless steel
• Oxide coating aids lubrication retention and reduces friction
• 2B class of fit meets standard tolerance requirements for general assembly
• Spiral point geometry pushes chips forward, ideal for through-hole applications

Compatibility

Designed for through-hole tapping of stainless steel and similar ferrous materials where a 5/16-18 UNC 2B thread form is required.

Installation Notes

This tap is installed and operated by machinists or maintenance technicians using a tapping machine, CNC machining center, or manual tapping arm. Ensure the workpiece is securely fixtured and the spindle is properly aligned before engaging the tap to prevent breakage. Use an appropriate cutting fluid or tapping compound compatible with stainless steel to extend tool life and achieve a clean thread form. Inspect the tap for wear or chipping before each use and replace if cutting edges show visible damage.