Sada špirálových vrtákov KWB 421920 19 ks pravotočivá

The KWB 421920 twist drill bit set is a 19-piece collection of right-hand rotation HSS drill bits manufactured to DIN 338 standards. These roll-forged, steam-hardened bits have a blue-black finish and a 118° tip angle, suitable for drilling in alloyed and mild steel, castings, non-ferrous metals and hard plastics. The set is intended for general drilling tasks where durability and dimensional accuracy are required.

Advantages

Roll forging and steam hardening increase toughness and wear resistance while preserving cutting geometry. The blue-black surface treatment provides corrosion protection and a uniform appearance. A 118° tip angle and type N geometry offer a balance between cutting efficiency and longevity when working with steels and non-ferrous materials. Compliance with DIN 338 ensures consistent dimensions and compatibility with standard tool holders.

Suitable for

Key specifications

How to use

Secure the appropriate drill bit in the chuck of a drill or drill press, ensuring it is concentric and firmly clamped. Select suitable spindle speed for the material (lower speeds for steels, higher for non-ferrous metals and plastics) and apply steady feed pressure. Use cutting fluid when drilling steels and castings to reduce heat and extend tool life. Clear chips regularly to avoid clogging and maintain hole quality.

Recommendations

For best results, match drill speed and lubrication to the work material: use cutting oil for alloyed and mild steels, lighter lubrication or air cooling for non-ferrous metals and plastics. Replace worn bits to maintain hole accuracy and reduce risk of workpiece damage.