Data Sheet

08
201
7
15
11
33
14
105
0
20
40
60
80
100
120
Ø 12,0 mm Ø 20,0 mm Ø 30,0 mm
Ø 12,0 mm Ø 20,0 mm Ø 30,0 mm
Main application Other application
Comparison of cutting times core drills
HSS vs. twist drills HSS DIN 345
Drilling time in seconds
Workpiece: steelgirder
Material: construction steel S235JR
Cutting depth: 12,0 mm
Machine: RUKO Magnetic-stand drilling machine RS140
Cutting with twist drills has been made without pilot drilling
directly into the material. No cooling or lubrication has been used.
Core drills HSS Twist drills HSS DIN 345
Cuttingvolumewith:
Twist drills
Cuttingvolumewith:
Core drills
Coredrillscutuptotentimesfasterthantwistdrills.Coredrillsonlycutthewidthoftheteeth.Thecoreisejected.Lowerenergyrequirementsand
lesswearresultinalongerworkinglife.Twistdrillshavetomachinetheentirediameterofthehole.Thiscallsforconsiderabledownwardpressure
andhighdrivingpower.
RUKOcoredrillswillsavecostsandtime.Ascoredrillsonlycutthewidthoftheteethandastwistdrillscuttheentirediameterofthehole,coredrills
are many times faster (see diagram). Centering and pilot drilling are not necessary anymore.
Considerablyimprovedcuttingbehaviourwasattainedbyresearchintothecuttinggeometry,
which has a beneficial effect on cutting performance and drill life.
1. Optimised cutting edge geometry for increased cutting performances and reduced cutting
forces.
2. Theeffectivecuttinganglesaredesignedforuniversaluseinvarioussortsofsteel.
3. ImprovedremovalofchipsthankstoU-shapedrecesses.Thespecificgeometryoftherecess
reducesthethermalloadontheHSScoredrillastheheatcreatedincuttingisremovedwith
thechipstoaverygreatextent.
4. Reduction of the friction between the HSS core drill and the workpiece thanks to optimised
spiral-shaped guide chamfers.
The cutting edge is the important thing ...