Drill bit Proline 7.3 mm NWKk DIN 1897 RN HSS, ground 74-34

Proline 7.3 mm NWKk DIN 1897 RN HSS twist drill is a high-speed steel drill bit designed to meet DIN 1897 standards. The RN (reduced nose) point geometry and ground finish (designation 74-34) provide accurate centering and improved surface quality on drilled holes. Intended for general workshop and metalworking tasks, this drill bit suits operations where a standardized DIN 1897 HSS tool is required.

Advantages

The HSS material ensures good wear resistance and hot hardness for sustained cutting performance in metal. Ground flutes and the 74-34 finish deliver precise cutting edges and smoother hole walls, while the RN point reduces walking at contact and improves initial hole positioning. The NWKk shank and twist-drill geometry provide predictable chip removal and stable drilling in a range of ferrous and non-ferrous materials.

Suitable for

• Drilling holes in mild steel, alloy steel and cast iron
• General workshop and maintenance drilling tasks
• Bench or machine drilling where DIN 1897 twist drills are specified
• Drilling operations requiring precise centre-running and good surface finish

Key specifications

• Diameter: 7.3 mm
• Material: High-speed steel (HSS)
• Point type: RN (reduced nose) for improved centring
• Standard: DIN 1897 twist drill geometry
• Finish: Ground cutting edges and flutes (74-34)
• Shank type: NWKk twist-drill shank

How to use

Mark the drilling position and secure the workpiece to prevent movement. Select appropriate spindle speed and cutting fluid for the work material—lower speeds and coolant for harder steels, higher speeds for softer materials. Align the drill perpendicular to the surface and apply steady, moderate feed pressure to allow chip clearance. Retract periodically on deep holes to remove chips and reduce heat build-up. Inspect the hole and tool periodically for wear or damage.

Usage recommendations

Use cutting fluid when drilling steel to extend tool life and improve surface finish. Replace the drill if flank wear or chipping affects hole quality. For repetitive or production work, monitor speeds and feeds to balance tool life and machining time.