Kennametal 4150253 Screw Machine Drill Bit 8mm Carbide

Product Description

The KENNAMETAL 4150253 is a screw machine length (stub length) solid carbide drill bit designed for precision drilling in metal fabrication, machining, and tooling applications. Built to DIN 6537K standards, this 8.00 mm diameter bit features a 140-degree point angle and a multilayer TiAlN coating at the tip for extended wear resistance and heat dissipation at cutting speeds common in CNC and manual drill press operations. The overall length is 79.00 mm (3.1102 inches), making it compact and rigid for reduced deflection in short-hole drilling. It is part of Kennametal series B041A-CPG and is sized for use in standard straight-shank toolholders and chucks.

This drill bit is suited for production machining environments where hole depth requirements are modest and rigidity is a priority. The stub length format limits overhang, which reduces vibration and improves hole location accuracy compared to jobber-length alternatives. Typical applications include drilling steel, cast iron, and similar ferrous materials on CNC machining centers, turret lathes, and drill presses. The 3xD flute-to-diameter ratio and tapered web configuration support chip evacuation in short, blind, or through-hole drilling tasks. Licensed machinists and tool-and-die technicians are the primary installers and users of this bit.

Key Features

• Solid carbide construction for rigidity and wear life in ferrous and hard materials
• TiAlN tip coating resists heat buildup and extends cutting edge life
• 140-degree point angle reduces thrust force and centers the drill on entry
• DIN 6537K specification ensures dimensional consistency for toolholder compatibility
• Stub length (3xD ratio) minimizes deflection in short-hole applications
• Straight cylindrical shank fits standard drill chucks and collet holders without modification

Compatibility

Designed as an OEM-specification solid carbide stub drill for use in straight-shank toolholders and drill chucks accepting an 8.00 mm (0.3150 inch) shank diameter, conforming to DIN 6537K dimensional standards.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists familiar with cutting tool safety and machine setup procedures. Ensure the spindle is fully stopped and the machine is powered down before inserting or removing the bit from the chuck or collet holder. Confirm shank seating depth and runout with a dial indicator before beginning a production run. Do not exceed the maximum drilling depth of 29.00 mm (1.1417 inches) per the tool geometry rating.