Guhring 9039400079380 Thread Forming Tap 5/16-18 Unc

Product Description

The GUHRING 9039400079380 is a thread forming tap designed for producing internal threads without cutting chips, reducing the risk of chip contamination in blind and through-hole applications. Built from High-Speed Steel-E-CO (cobalt-enhanced HSS) and coated with Titanium Nitride (TiN), this tap delivers extended tool life in demanding production environments. It is configured with a Modified Bottoming chamfer of 2-3 threads, making it well-suited for threading close to the bottom of blind holes. With a thread limit of H8/H9 and a 2BX class of fit, it produces consistent, accurate threads at the tighter end of the tolerance range. HVAC, plumbing, and general manufacturing technicians use thread forming taps where chip-free threading is critical to assembly integrity.

This tap is part of GUHRING Series 3940 and is sized for 5/16-18 UNC right-hand threads. It is engineered for use in steel, stainless steel, cast iron, and non-ferrous metals, covering a broad range of trade and industrial applications. The flute-by-diameter ratio of 3xD and five oil grooves support adequate lubrication during the forming process. It handles both blind-hole threading and through-hole threading, making it a versatile choice for fabrication shops, maintenance facilities, and production lines working in mixed material environments.

Key Features

• High-Speed Steel-E-CO (cobalt) construction for increased hardness and heat resistance
• Titanium Nitride (TiN) coating reduces friction and extends tool life
• Modified Bottoming chamfer (2-3 threads) enables threading close to blind hole bottoms
• 2BX class of fit with H8/H9 thread limit for tight-tolerance thread production
• Five oil grooves support consistent lubrication across the forming zone
• Suitable for blind-hole and through-hole threading in steel, stainless steel, cast iron, and non-ferrous metals

Compatibility

Designed for use in materials coded P (steel), M (stainless steel), K (cast iron), and N (non-ferrous metal). Suitable for 5/16-18 UNC threaded assemblies requiring a 2BX class of fit in both blind-hole and through-hole configurations.

Installation Notes

Thread forming taps are typically installed and operated by machinists and tool-and-die or maintenance technicians using a tapping machine, CNC machining center, or hand tap wrench. The workpiece must be secured and the correct tap drill size used for the specific material to maintain the proper thread engagement ratio. Always apply an appropriate tapping fluid or cutting oil to the oil grooves before and during use. Do not attempt to back the tap out under power if it becomes bound — disengage and back out manually to avoid breakage.