Guhring 9019790079380 Straight Flute Tap 5/16-18 Unc

Product Description

The GUHRING 9019790079380 is a straight flute tap designed for cutting internal threads in both blind hole and through-hole applications. Built from cobalt high-speed steel with an oxide finish, this tap handles demanding materials including gray cast iron, malleable iron, and spheroidal iron. It cuts a 5/16-18 UNC right-hand thread to a 2B class of fit with a thread limit of H4/H5. The modified bottoming chamfer allows threading close to the bottom of blind holes without sacrificing thread quality. With 4 flutes and a 90 mm overall length, it is suited for production and maintenance machining environments where consistent thread form is required.

This tap is used in machine shop and maintenance settings where UNC internal threads are required in ferrous materials. The modified bottoming chamfer makes it effective in blind hole applications where full thread depth near the bottom is necessary, while also performing in through-hole threading. With a shank diameter of 8 mm and a square length of 6.20 mm, it fits standard tap holders and machine spindles used in CNC and manual tapping operations. It is part of the GUHRING Series 1979 straight flute tap line.

Key Features

• Cobalt high-speed steel construction for improved wear resistance in ferrous and abrasive materials
• Modified bottoming chamfer for threading close to the base of blind holes
• 4 straight flutes for efficient chip evacuation in through-hole and blind hole applications
• Oxide finish reduces friction and improves chip flow during tapping
• 2B class of fit with H4/H5 thread limit for standard UNC tolerance requirements
• Right-hand thread direction, compatible with standard tapping equipment

Compatibility

Designed for blind hole and through-hole threading in gray cast iron, malleable iron, and spheroidal iron. Fits standard 8 mm shank tap holders and machine spindle adapters used with manual and CNC tapping equipment.

Installation Notes

This tap should be installed by a machinist or tooling technician using a properly sized tap holder matched to the 8 mm shank diameter. Ensure the workpiece is securely fixtured before beginning the tapping cycle and that cutting fluid appropriate for ferrous materials is applied. For blind hole applications, set depth stops carefully to avoid bottoming the tap under torque. Follow shop safety procedures and machine manufacturer guidelines when setting spindle speed and feed rate.