Trepanning is used for larger hole diameters and where machine power is limited, because it is not as powerconsuming as solid drilling. The trepanning tool does not machine the whole diameter, only a ring at the periphery.
Instead of removing all the material in the form of chips, a core is left in the centre of the hole – consequently, this method is for through-hole applications.
Use T-Max® U Trepanner R416.7 for trepanning.
DC, mm (inch)
||2.5 x DC|
Rotating and non-rotating drills
The peripheral insert must be set 0.20 mm (0.008 inch) behind the inner cartridge.
- The drill should be positioned with the inserts on the horizontal axis.
- The drill must not be offset from the workpiece centerline, with reference to the peripheral insert, by more than -0.15 mm (0.006 inch).
- The peripheral cutting edge (P) should be set to within +0.1 mm (0.004 inch) in the horizontal plane from the centre-line of spindle (CL).
Vertical set up
The core will fall down when drill breaks through, which does not normally cause a problem.
Long and heavy cores may require a core support to prevent the core from falling down and chipping the inner insert.
Rotating drill - core fixing
Drill a hole into the core. Fix plug in the hole to prevent the core (C) from falling.
Non-rotating drill - core support
If the drill is fitted with a core support, the drill should be mounted with the
cartridges located on the vertical axis and the peripheral insert downwards.
|| Stainless steel
|| Cast iron
Graphs for T-Max® U trepanning tools – R416.7