Accupro T2644443 Spiral Flute Tap 5/16-18 2 Flute Hss

Product Description

The ACCUPRO T2644443 is a spiral flute tap designed for cutting 5/16-18 unified coarse internal threads in a range of workpiece materials. Built from 3% Vanadium High Speed Steel (HSS), this tap delivers increased wear resistance compared to standard M2 HSS tooling. The modified bottoming chamfer allows thread cutting closer to the bottom of a blind hole than a plug or taper style. With a 40-degree helix angle and fast flute style, chips are efficiently evacuated up and out of the hole during the tapping operation. The bright, uncoated finish makes it straightforward to inspect for wear. Overall length is 2.7188 inches and thread limit is H3.

This tap is suited for general machining, maintenance, and fabrication environments where 5/16-18 blind or through-hole threading is required. The modified bottoming chamfer makes it a practical choice when threaded depth in a blind bore is critical. The right-hand flute and right-hand thread configuration cover the most common tapping requirement in shop and field settings. Machinists, millwrights, and maintenance technicians working in job shop, production, or MRO contexts will find this tap appropriate for steel, aluminum, and similar machinable metals. Coolant-through capability is not provided on this tool.

Key Features

• 3% Vanadium HSS construction for improved wear resistance over standard HSS
• Modified bottoming chamfer for threading closer to the base of blind holes
• 40-degree helix angle with fast flute style promotes efficient chip evacuation
• H3 thread limit for 3B class of fit — suitable for standard tolerance threaded assemblies
• Right-hand flute and right-hand thread — compatible with conventional tapping equipment
• Bright/uncoated finish allows easy visual wear inspection

Compatibility

Designed as an OEM-style replacement or direct-use spiral flute tap for 5/16-18 tapping applications. Fits standard tap holders and tapping heads that accept the 8.08 mm shank diameter.

Installation Notes

This tap should be installed in a tap wrench, tapping head, or CNC spindle rated for the shank diameter before use. Secure the workpiece fully before beginning the tapping operation. Use appropriate cutting fluid for the workpiece material to extend tool life and improve thread finish. Inspect the tap for chipping or wear before each use, and never force a tap that has stopped advancing, as breakage can result.