Osg 2531201 Spiral Point Tap 5/16-24 Unf 3 Flute Plug

Product Description

The OSG 2531201 is a spiral point plug tap designed for threading 5/16-24 UNF internal threads in a wide range of ferrous and non-ferrous materials. Built from vanadium high-speed steel (HSS-E) with a steam oxide coating, this tap offers improved lubricity and corrosion resistance during cutting operations. It features a 3-flute spiral point geometry that pushes chips forward ahead of the cutting zone, making it well-suited for through-hole tapping applications. The H2 thread limit holds tight tolerances to produce a 2B class of fit. Overall length is 3.543 inches with a thread length of 1.125 inches and a shank diameter of 0.318 inches.

This tap is intended for use in machine tapping operations across production and maintenance environments. It handles a broad material range including aluminum, low-carbon steel, medium-carbon steel, high-carbon steel, alloy steel, die steel, stainless steel, cast iron, and hardened steel. Right-hand thread direction makes it compatible with standard CNC machining centers, drill presses, and tapping arms. It is commonly used by machinists, tool and die makers, and maintenance mechanics in manufacturing, fabrication, and repair shops where consistent 5/16-24 UNF thread quality is required.

Key Features

• Spiral point geometry pushes chips forward for clean through-hole tapping
• Vanadium high-speed steel (HSS-E) construction for improved wear resistance
• Steam oxide coating reduces friction and improves chip evacuation
• H2 thread limit produces accurate 2B class of fit threads
• 3-flute design for balanced cutting load and stable thread form
• Plug chamfer provides gradual thread engagement suitable for most through-hole applications

Compatibility

Designed for through-hole tapping of 5/16-24 UNF threads in aluminum, hardened steel, stainless steel, high-carbon steel, low-carbon steel, medium-carbon steel, alloy steel, die steel, and cast iron.

Installation Notes

Install in a rigid tapping chuck or floating tap holder to minimize axial runout and protect the tap from breakage. Power down and secure the workpiece before changing tooling. Apply a suitable cutting fluid or tapping compound for the material being threaded to extend tool life. Coolant-through is not supported on this tap, so external lubrication at the cutting zone is recommended.