Osg 2832208 Spiral Point Tap 7/16-20 Unf Ticn Hss

Product Description

The OSG 2832208 is a spiral point plug tap designed for threading 7/16-20 UNF internal threads in a wide range of ferrous and non-ferrous materials. Built from Vanadium High Speed Steel (HSS-E) and finished with a Titanium Carbonitride (TiCN) coating, this tap delivers improved wear resistance and surface hardness compared to uncoated tooling. The 3-flute spiral point geometry pushes chips forward ahead of the cut, making it well-suited for threading through-holes without chip packing. Overall length is 3.157 inches with a thread length of 0.858 inches and a shank diameter of 0.323 inches. Thread limit is H3, indicating a standard tolerance class for general-purpose threading applications.

This tap is intended for use in through-hole threading operations across production and maintenance machining environments. Suitable material applications include aluminum, low-carbon steel, medium-carbon steel, high-carbon steel, alloy steel, die steel, stainless steel, and cast iron. The plug chamfer provides a gradual lead-in over several threads, making it appropriate for starting threads in through-holes or where a bottoming tap is not required. It is used by machinists, tool and die makers, and maintenance technicians working with manual or CNC tapping equipment. Coolant-through capability is not included on this tap.

Key Features

• 7/16-20 UNF thread form with right-hand thread direction
• 3-flute spiral point geometry pushes chips forward for clean through-hole threading
• TiCN coating increases surface hardness and extends tool life in abrasive materials
• Vanadium High Speed Steel (HSS-E) construction for toughness in interrupted and varied materials
• Plug chamfer for gradual thread lead-in in through-hole applications
• H3 thread limit for standard general-purpose tolerance class

Compatibility

Designed for through-hole tapping of 7/16-20 UNF threads in aluminum, stainless steel, carbon steels, alloy steel, die steel, and cast iron workpieces. No specific machine or system compatibility is stated by the manufacturer for this part.

Installation Notes

Install in a tapping chuck, tap holder, or CNC rigid tapping spindle rated for the shank diameter of 0.323 inches. Ensure the workpiece is securely fixtured and the tap is properly aligned to avoid tap breakage or cross-threading. Apply appropriate cutting fluid for the material being tapped; HSS-E taps benefit from sulfo-chlorinated cutting oil in ferrous materials and water-soluble coolant in aluminum. Always back the tap out periodically to clear chips when operating near the bottom of a through-hole.