Balax 13172-91C Thread Forming Tap 5/16-18 Unc Bottoming Ticn

Product Description

The BALAX 13172-91C is a bottoming-style thread forming tap designed for producing 5/16-18 UNC internal threads in steel workpieces. Unlike cutting taps, this fluteless forming tap displaces material rather than removing chips, generating stronger threads with no swarf in the hole. It is manufactured from powdered metal high-speed steel for uniform grain structure and enhanced wear resistance, and features a TiCN coating to reduce friction and extend tool life in production environments. With an H9 thread limit and a 2B class of fit, it delivers consistent dimensional accuracy across high-volume tapping operations in machine shop and manufacturing settings.

This tap is intended for blind hole threading applications in steel materials, making it well suited for CNC machining centers, drill presses, and tapping machines where controlled feed rates can be maintained. The bottoming chamfer, with 2.5 chamfered threads, allows threading close to the bottom of a blind hole where a plug or spiral chamfer would leave unformed threads. It is typically specified by machinists and tool-and-die professionals working on ferrous components requiring precise, chip-free thread formation.

Key Features

• Thread forming design displaces material for stronger, chip-free threads in blind holes
• Powdered metal high-speed steel construction provides consistent hardness and wear resistance
• TiCN coating reduces friction and extends service life in steel tapping applications
• Bottoming chamfer with 2.5P allows threading close to the base of blind holes
• H9 thread limit ensures 2B class of fit compliance for standard UNC fastener engagement
• Single oil groove supports lubrication flow during the forming process

Compatibility

Designed for blind hole thread forming in steel workpieces requiring 5/16-18 UNC internal threads with a 2B class of fit. Fits standard machine tool holders accepting a 0.318-inch shank diameter.

Installation Notes

Thread forming taps require a properly sized forming tap drill - consult a forming tap drill chart for the correct hole diameter before use, as forming taps use a larger pilot hole than cutting taps. Ensure the machine spindle is powered down and the workpiece is securely fixtured before changing or setting tooling. Adequate lubrication or cutting fluid appropriate for steel is essential to prevent galling and premature tap wear. Right-hand spindle rotation is required for this tap.