Triumph Twist Drill 011528 Cobalt Drill Bit 7/16 in

Product Description

The TRIUMPH TWIST DRILL 011528 is a cobalt jobber-length drill bit designed for heavy-duty drilling in alloy and alloy steel workpieces. Built to Series T1C standards, it features a 135-degree split point for self-centering starts without a center punch, reducing walking on hard surfaces. The gold oxide coating adds surface hardness and heat resistance, extending tool life in demanding applications. At 5.5 inches overall length with a 4.0625-inch flute, it delivers the reach needed for production and maintenance drilling. The straight cylindrical shank fits standard three-jaw chucks with no adapters required.

This bit is suited for metal fabrication shops, maintenance and repair operations, and production environments where hard or work-hardened steels are common. The regular spiral flute and right-hand cut provide efficient chip evacuation in alloy steel. The web-thinned, tapered web configuration reduces thrust load at the cutting tip, making it practical for hand-held drill use as well as drill press work. Machinists, tool-and-die workers, and maintenance technicians are the primary users of this style of bit.

Key Features

• Cobalt construction for heat resistance and durability in alloy steel drilling
• 135-degree split point with web thinning for self-centering and reduced thrust
• Gold oxide coating for added surface hardness and extended tool life
• Regular spiral flute with right-hand cut for efficient chip removal
• Straight cylindrical shank fits standard three-jaw chucks directly
• Tapered web configuration reduces cutting force at tip

Compatibility

Designed as a jobber-length drill bit for use in standard three-jaw drill chucks accepting a 7/16-inch straight cylindrical shank. Primary workpiece materials include alloy and alloy steel.

Installation Notes

Install and remove drill bits only with the drill or drill press powered off and the chuck fully secured. Secure the workpiece firmly before drilling to prevent spinning or shifting under load. Verify chuck jaw condition before seating the shank to ensure concentric runout. Coolant through is not supported on this bit; use an appropriate cutting fluid applied externally when drilling hard alloys to manage heat buildup.