During the machining process, modern station tools use coolants, minimum quantity lubrication or pneumatics for blowing out the chips in case of dry machining depending on the type of material and production task.
Contrary to the past when the work piece was simply “flooded” with coolant, the medium is today transported through the spindle manufacturers and tool to the tool tip in a well directed way. This procedure calls for a rotating union at the end of the spindle, the function of which is to transfer the medium from the stationary supply lines to the fast rotating spindle.
These rotating unions are independent units.
They are then called “bearingless rotating unions” or “sealing cartridges".
The current development of the bearingless rotating unions shows two tendencies:

1. Miniaturisation
Constantly rising speeds initially caused to develop bearingless rotating unions whereby masses have already been saved.
But modern machining centres must feature even shorter changing times and movement around one or several axes with the highest precision. Accordingly, the machine engineer has to struggle with each half a gram of weight. If mass is saved in the area of the spindle, drives can be more compact, steady-state effects of masses can be reduced and energy can be saved.
DEUBLIN actively supports this approach by miniaturising the rotating unions, i.e. consistent reduction in size of the components. It goes without saying that this does not only mean a mere reduction in size, as the user expects the familiar precision and performance, but research regarding the limits of feasibility: .....