Sumitomo U101183 Screw Machine Drill Bit 31/64 Carbide

Product Description

The SUMITOMO U101183 is a screw machine length drill bit designed for high-performance drilling in demanding metalworking applications. Built from solid carbide with a coated finish, this bit measures 31/64 inch (0.4844 inches) in diameter and features a 135-degree split-point angle for accurate self-starting and reduced thrust. The straight-cylindrical shank seats securely in standard chucks and collets. With coolant-through capability and a tapered web configuration, the U101183 is suited for production environments where heat management and hole quality are critical. Licensed machinists, toolroom technicians, and CNC operators are the primary installers of this tooling.

This drill bit belongs to the MDW-HGS series and is rated for use in cast iron, stainless steel, and steel workpieces. The screw machine length profile keeps the tool compact and rigid, reducing deflection on short-reach setups and CNC machining centers. With a flute-to-diameter ratio of 3xD and a maximum drilling depth of 1.735 inches (44.07 mm), it is well matched to production drilling cycles where consistent hole geometry and tool life are priorities. It is packaged and sold individually.

Key Features

• Solid carbide construction with coated finish for extended tool life in ferrous materials
• 135-degree drill point angle for self-centering entry and reduced walking on hardened surfaces
• Coolant-through design channels cutting fluid directly to the cutting edge for heat control
• Tapered web configuration improves chip evacuation and reduces cutting force
• Straight-cylindrical shank with h8 diameter tolerance for precise chuck and collet fit
• Screw machine length body provides rigidity and minimizes runout on short-reach setups

Compatibility

Designed for use in cast iron, stainless steel, and steel workpieces; fits standard drill chucks and collets accepting a 0.4844-inch straight-cylindrical shank within the MDW-HGS series range of 0.4500 to 0.5000 inches diameter.

Installation Notes

This tooling is installed by machinists and CNC setup technicians in machine tool spindles or toolholders rated for carbide tooling. Ensure the machine spindle and chuck or collet are clean and within tolerance before seating the shank. Carbide is brittle — avoid side loads, interrupted cuts without proper feeds and speeds, or dropping the tool on hard surfaces. Confirm coolant-through passages in the holder are clear and that coolant pressure is appropriate for the application before beginning a drilling cycle.