Allied Machine 20831-1250 Indexable Spade Drill Hp-c

Product Description

The ALLIED MACHINE AND ENGINEERING 20831-1250 is an indexable spade drill body engineered for high-performance hole-making in a wide range of workpiece materials. It accepts spade drill inserts and covers a drilling diameter range of 1-1/2 inches to 2-3/8 inches, with a maximum drill depth of 8-1/2 inches. The straight flute design and through-coolant capability help evacuate chips and manage heat at the cutting zone. The body measures 12-1/2 inches overall length with a 1-1/4 inch flatted shank for positive drive. Machinists and CNC operators in production and job-shop environments install this tool on machining centers and lathes equipped with appropriate coolant supply.

This drill body belongs to the HP-C Series, which is rated for high-performance applications across universal workpiece material categories including cast iron, steel, non-ferrous alloys, and non-metallic materials. The standard-length body configuration suits production drilling operations where depth-to-diameter ratios are moderate. It is appropriate for both horizontal and vertical machining centers that can supply internal coolant through the spindle or through a dedicated coolant fitting at the shank.

Key Features

• Drilling diameter range: 1-1/2 inches to 2-3/8 inches for flexible insert selection
• Maximum drill depth of 8-1/2 inches with an 8-1/2 inch flute length for full-depth chip clearance
• Through-coolant design with axial concentric and radial coolant entry (1/4 inch NPT coolant hole thread) for effective heat and chip management
• Flatted cylindrical shank at 1-1/4 inch diameter provides secure, anti-rotation drive in standard tool holders
• HP-C Series high-performance rating compatible with universal workpiece materials including steels, cast irons, and non-ferrous alloys
• Steel body construction with straight flute geometry for rigid, stable cutting action

Compatibility

Designed for use with compatible indexable spade drill inserts in the HP-C Series. Suitable for machining centers and turning centers equipped with 1-1/4 inch shank tooling and through-spindle or radial coolant supply capable of connecting to a 1/4 inch NPT coolant port.

Installation Notes

Installation should be performed by a qualified machinist or tooling specialist. Ensure the machine spindle is fully stopped and locked out before mounting or removing the drill body. Confirm the tool holder bore matches the 1-1/4 inch shank diameter and that the flatted drive surface engages the set screw correctly to prevent rotation under load. Verify the coolant supply is connected and tested at operating pressure before beginning the cut to protect both the insert and the workpiece.