Kennametal 4151172 Screw Machine Drill Bit 7.80mm Carbide

Product Description

The KENNAMETAL 4151172 is a screw machine length (stub length) drill bit engineered for high-performance drilling in metal and hard materials. Built from solid carbide and coated with a multilayer TiAlN finish at the tip, it delivers superior heat resistance and extended tool life compared to high-speed steel alternatives. The 140-degree split point reduces walking on entry and lowers thrust force during penetration. At 7.80 mm in diameter with a 79.00 mm overall length and a 2-flute regular spiral geometry, this bit is sized for compact, high-rigidity setups common in CNC machining and screw machine operations. Coolant-through design supports internal chip evacuation and thermal management at the cutting zone.

This drill bit is suited for use in CNC machining centers, turret lathes, and screw machines where short, rigid tooling is required. The stub-length body minimizes deflection in tight-clearance bores and short-reach applications. The straight cylindrical shank accommodates standard drill chucks and collet systems. It is typically installed by machinists and CNC operators in production environments handling ferrous metals, cast iron, and alloyed steels. The 3xD flute-to-diameter ratio supports controlled chip flow in shallow-to-moderate depth holes up to 29.00 mm deep.

Key Features

• Solid carbide construction for rigidity and wear resistance in hard-material drilling
• Multilayer TiAlN coating at the tip for elevated heat resistance and longer tool life
• 140-degree point angle reduces thrust and minimizes bit walking on entry
• Coolant-through design enables internal flushing for chip evacuation and heat control
• Stub length body minimizes deflection in short-reach and tight-clearance applications
• Conforms to DIN 6537K specification for consistent dimensional tolerancing

Compatibility

Designed as an OEM-style replacement fitting standard drill chucks and collet systems that accept an 8.00 mm straight cylindrical shank, within the KENNAMETAL Series B051A-CPG stub-length solid carbide drill line.

Installation Notes

Installation is performed by qualified machinists or CNC operators. Before changing tooling, power down the machine and confirm the spindle has fully stopped. Seat the straight shank fully in the collet or chuck and torque the retention mechanism per the machine tool manufacturer specifications. Verify coolant-through lines are clear and delivering adequate flow before initiating the first cut to protect the cutting edge and aid chip removal.