Sandvik Coromant 8248381 Thread Forming Tap 3/8-16 Unc 2B

Product Description

The SANDVIK COROMANT 8248381 is a thread forming tap designed for creating internal threads in ductile metals without cutting or removing material. Part of the CoroTap 400 series, this tap uses a modified bottoming chamfer with 2-3 chamfered threads, allowing it to work close to the bottom of a blind hole. It is manufactured from powder-metallurgy high-speed steel and coated with titanium nitride for improved wear resistance and tool life. With an overall length of 3.937 inches and a tapping depth of 1.535 inches, it is sized for 3/8-16 UNC threads to a 2B class of fit. Licensed machinists and CNC programmers working in ferrous and non-ferrous machining environments typically spec and install this tool.

This tap is suited for both blind hole threading and through-hole threading applications in materials classified under grades P, M, N, and S, covering steels, stainless steels, aluminum alloys, and heat-resistant superalloys. The T400-XM150AE series is commonly used in production machining environments where thread quality, tool consistency, and reduced scrap rates are priorities. Its form-tapping action is particularly effective in softer, ductile materials where cold-forming produces stronger threads than cut tapping.

Key Features

• Modified bottoming chamfer with 2-3 chamfered threads for close-to-bottom reach in blind holes
• Powder-metallurgy high-speed steel construction for consistent grain structure and edge toughness
• Titanium nitride coating reduces friction and extends tool life in production runs
• 6 oil grooves support lubrication distribution during the forming process
• Right-hand thread direction, 3/8-16 UNC, 2B class of fit
• Compatible with blind hole and through-hole threading applications across multiple material grades

Compatibility

Designed for use in materials with application codes P, M, N, and S, including steels, stainless steels, non-ferrous metals, and heat-resistant superalloys. Suited for blind hole and through-hole threading operations requiring a 3/8-16 UNC, 2B class of fit thread form.

Installation Notes

Thread forming taps require adequate lubrication or cutting fluid at the point of contact; use a lubricant rated for the specific workpiece material. Always ensure the tap is properly aligned with the pre-drilled forming hole, as form taps require a larger pilot hole diameter than cut taps for the same thread size. Power down or de-energize the machine spindle before installing or removing the tap from the holder. Follow applicable shop safety protocols and machine tool manufacturer guidelines during setup and operation.