Kennametal 4131189 Spiral Point Tap 1/2-20 Unf Hss Oxide

Product Description

The KENNAMETAL 4131189 is a spiral point tap designed for cutting internal threads in through-hole applications. It is manufactured from high speed steel (HSS) with an oxide finish and carries a 1/2-20 UNF thread form with a plug chamfer. The H3 thread limit and Class 3B fit deliver close-tolerance threads suited to precision fastening work. With 3 flutes and a right-hand cutting direction, the tap pushes chips forward ahead of the cutting zone, reducing clogging in production drilling and tapping operations. Machinists and tool room technicians use this tap in manual and machine tapping setups.

This tap is suited for threading through-holes in cast iron, ductile iron, stainless steel, and steel. The plug chamfer — typically 3 to 5 threads of taper — makes it a general-purpose choice for both hand tapping and CNC tapping centers where blind-hole entry is not required. The 3-3/8 inch overall length accommodates standard tap holders and extension chucks used in vertical and horizontal machining centers as well as drill press setups.

Key Features

• 1/2-20 UNF thread form with H3 thread limit for Class 3B close-tolerance fits
• High speed steel construction provides wear resistance across ferrous material applications
• Oxide finish reduces friction and provides light corrosion resistance during storage and use
• Plug chamfer allows use in through-hole tapping with machine or hand tapping equipment
• Spiral point geometry pushes chips forward, reducing chip packing in through-hole operations
• Right-hand cutting direction — compatible with standard right-hand tapping attachments and spindles

Compatibility

Designed for use in cast iron, ductile iron, stainless steel, and steel workpieces requiring a 1/2-20 UNF internal thread. Coolant-through tooling is not supported by this tap; external coolant or cutting fluid application is recommended where applicable.

Installation Notes

This tap should be installed by a qualified machinist or tool room technician familiar with tapping speeds, feeds, and alignment requirements for HSS tooling. Secure the tap in a properly sized tap holder or floating tap chuck to prevent binding and tap breakage. Apply appropriate cutting fluid for the workpiece material before and during tapping. Always back the tap out periodically in hand tapping to break and clear chips.