Osg 1400130505 Thread Forming Tap 5/16-18 Unc Cobalt Tin H3

Product Description

The OSG 1400130505 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting or producing chips. Operating on a 5/16-18 UNC thread specification with a right-hand thread direction and H3 thread limit, this tap displaces material rather than removing it, producing stronger threads with better surface finish. Manufactured from cobalt high-speed steel and finished with a TiN coating, it delivers extended tool life in demanding materials. The modified bottoming chamfer features 2 to 2.5 chamfered threads, allowing the tap to thread close to the bottom of a blind hole. Overall length is 2.719 inches with a shank diameter of 0.318 inches.

This tap is engineered for blind hole threading applications across a broad range of metallic workpiece materials including alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. It is well suited for production environments where chip evacuation is a concern and thread strength is critical. The HY-PRO NRT series is a common choice for CNC tapping centers and manual tapping in fabrication, tooling, and precision machining shops. Material application codes P and N confirm suitability for steel and non-ferrous alloy families.

Key Features

• Thread forming design eliminates chips, reducing tap breakage risk in blind holes
• Cobalt HSS construction resists heat and wear in tough alloys and stainless steel
• TiN coating reduces friction and extends tool service life
• Modified bottoming chamfer (2 to 2.5 threads) enables threading close to hole bottom
• H3 thread limit provides consistent fit for 5/16-18 UNC standard fastener engagement
• Right-hand thread direction, compatible with standard tapping spindles and tap handles

Compatibility

Designed for blind hole threading in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Fits standard 5/16-18 UNC tapping applications requiring an H3 thread limit. Compatible with CNC tapping centers and manual tap wrenches accepting a 0.318-inch shank diameter.

Installation Notes

Thread forming taps require proper hole sizing — use the recommended form tap drill size for the specific material to ensure correct thread fill and prevent tap breakage. Apply appropriate tapping fluid or cutting oil for the workpiece material before and during the tapping operation. Ensure the tap is properly aligned perpendicular to the workpiece surface before applying torque. For CNC applications, verify spindle speed and feed rate are set to manufacturer-recommended values for thread forming in the target material.