Guhring 9048855079380 Spiral Point Tap 5/16-18 Unc Hss-e

Product Description

The GUHRING 9048855079380 is a spiral point tap designed for right-hand through-hole threading in steel applications. It cuts a 5/16-18 UNC thread profile with 3 flutes and a plug chamfer entry, pushing chips forward through the hole rather than packing them into the flute. The tap is manufactured from HSS-E cobalt high-speed steel and carries a GUHRING Ignator coating, which improves surface hardness and heat resistance during high-speed tapping cycles. Thread limit is H4/H5, making it suitable for both 2B and 3B class-of-fit tolerances. It is installed by machinists, toolroom technicians, and maintenance professionals working on threaded fastener applications in steel components.

This tap is intended for through-hole threading operations in steel workpieces where chip evacuation forward through the hole is acceptable and preferred. The plug chamfer provides a moderate starting lead, making it practical for production tapping in CNC machining centers, drill presses, and manual tapping setups. It is appropriate for residential and commercial maintenance, fabrication shops, and production machining environments handling 5/16-18 UNC fastener specifications. Coolant-through is not supported in this configuration.

Key Features

• 5/16-18 UNC thread form with right-hand cut direction
• 3-flute spiral point geometry pushes chips forward for clean through-hole threading
• Plug chamfer provides moderate starting lead for production and manual use
• HSS-E cobalt base material improves toughness and wear resistance in steel
• Ignator coating adds surface hardness and reduces heat buildup at the cutting edge
• H4/H5 thread limit supports both 2B and 3B class-of-fit tolerances

Compatibility

Designed for through-hole tapping in steel. Rated for 2B and 3B class-of-fit applications per UNC thread standards. Part of GUHRING Series 4885.

Installation Notes

This tap is installed by machinists or maintenance technicians using a tapping head, CNC rigid tap cycle, or manual tap wrench. Ensure the workpiece is securely fixtured and the pilot hole diameter is correct for 5/16-18 UNC before beginning. Apply appropriate cutting fluid for the material being tapped. Do not reverse the tap under load without confirming the machine cycle supports it, and do not exceed the recommended speed range for HSS-E tooling in steel.