Deep hole drilling
Requirement deep hole drilling
For good hole drilling results, cooling, lubrication and high-pressure coolant systems are required. Single flue gundrilling cannot only be achieved on deep drilling machines but is also very good on machining centers (drilling, turning and milling center) with:
- Deep-hole drilling oil,
- Emulsion (min. 10 – 12 % concentration, with additives),
- and under conditions, with a minimum quantity air/lubrication system
The prevent outbreaks during retraction of single flute gundrill we recommend plunging in counterclockwise rotation.
Too big a diameter difference between the tool and drill bush or pilot hole can cause the following problems:
- poor hole quality
- excessive hole straightness deviation
- drill breakage
Drill bushing has a form set against the workpiece!
Recommendation: pilot drill with m7 tolerance.
Deep drilling machine
- Make a pilot hole
- Enter with stationary spindle or speed < 50 rpm
- Set coolant pressure, speed and feed
- Continuous drilling to depth without peck
- Switch off coolant supply after reaching hole depth
- Retraction with stationary spindle or < 50 rpm
Special nose grinds
Summary table Typ 100, Typ 110, Typ 120