Drill bit GRAPHITE 9 mm cobalt for metal, cylindrical shank (57H050)

GRAPHITE cobalt 9 mm metal drill bit with a cylindrical shank is designed for drilling hard and alloyed ferrous materials. Made from a cobalt-enriched high-speed steel alloy, the drill bit offers improved heat resistance and wear durability compared with standard HSS bits. The cylindrical (straight) shank fits common chucks in hand drills and drill presses, making it suitable for workshop and industrial use when accurate, repeatable holes in steel and similar metals are required.

Advantages

The cobalt alloy composition increases red-hardness and extends tool life under high cutting temperatures, reducing wear during prolonged or heavy-duty drilling. The 9 mm diameter provides a balance between structural rigidity and cutting efficiency, while the precision-ground flutes ensure effective chip evacuation and reduced clogging. The straight cylindrical shank allows secure clamping in conventional drill chucks and collets.

Suitable for

• Drilling holes in stainless steel and high-strength alloy steels
• Workshop and maintenance operations with hand-held drills
• Use in drill presses for repeatable and accurate hole making
• Repair, fabrication and metalworking tasks requiring durable cutting performance

Key specifications

• Diameter: 9 mm
• Material: cobalt-enriched high-speed steel
• Shank type: cylindrical (straight) shank
• Intended use: drilling in ferrous metals and alloy steels
• Flute type: precision-ground for chip removal

How to use

Secure the drill bit in the chuck or collet of a suitable hand drill or drill press, ensuring the shank is clamped fully and concentrically. Use appropriate spindle speed and feed rate for the material being drilled: lower speeds for harder or thicker steels, higher speeds for softer ferrous materials. Apply steady pressure without excessive force to avoid bit breakage and allow coolant or cutting fluid to reduce heat and improve chip evacuation. Withdraw the bit periodically to clear chips when drilling deep holes.

Usage recommendations

For best results, use cutting fluid or coolant when drilling stainless or high-alloy steels, and start with a small pilot hole when precision and centring are critical. Inspect the cutting edges regularly and replace the bit when wear or chipping reduces performance.