Kennametal 4151228 Stub Drill Bit 15/32 in Solid Carbide

Product Description

The KENNAMETAL 4151228 is a stub-length (screw machine length) drill bit designed for precision hole-making in demanding industrial and machining applications. Built from solid carbide and finished with a multilayer TiAlN coating at the tip, this bit delivers the hardness and heat resistance needed for high-speed drilling in ferrous metals, cast iron, and hardened materials. The 140-degree split-point geometry reduces thrust force and improves centering without a pilot hole. At 4.0157 inches overall length with a 2.1654-inch flute length, the compact stub design maximizes rigidity and minimizes deflection in short-reach setups.

This drill bit is suited for CNC machining centers, drill presses, and multi-spindle screw machines in production environments. The straight cylindrical shank measures 0.4724 inches in diameter, fitting standard toolholders and chucks. The coolant-through design supports high-pressure coolant delivery directly to the cutting zone, extending tool life in deep-hole and high-feed applications. It is part of the KENNAMETAL B051A-CPG series, conforming to DIN 6537K specification. Ideal for shops running tight-tolerance work where runout and drill diameter consistency are critical.

Key Features

• Solid carbide construction for maximum hardness and wear resistance
• Multilayer TiAlN (TiN at tip) coating for heat and oxidation resistance
• 140-degree standard point angle reduces entry thrust and improves self-centering
• Coolant-through design enables high-pressure internal coolant delivery
• Stub length profile maximizes rigidity and minimizes deflection
• Right-hand cut with regular spiral flute and tapered web for efficient chip evacuation

Compatibility

Designed as an OEM-style production drill for use in standard straight-shank toolholders and drill chucks compatible with a 0.4724-inch shank diameter. Conforms to DIN 6537K specification.

Installation Notes

Installation and tool changes should be performed by a qualified machinist with the machine powered down and the spindle fully stopped. Verify chuck or collet runout is within acceptable tolerance before seating the shank to protect the cutting edge and maintain hole accuracy. Use the coolant-through port connection appropriate to your machine spindle when activating high-pressure coolant. Do not exceed the maximum drilling depth of 1.5748 inches per pass without retracting to clear chips.