Rotary couplings without/with leackage return
Rotary couplings transmit hydraulic oil from a fixed to a rotating machine
part. The assembly is done in the rotating axis of the subassembly.
Depending on the number of junction levels several single- or double-acting
hydraulic elements can be connected. On principle, the rotary coupling is
only suitable for hydraulic oil.
If pneumatic shall be transferred, the catalogued elements can be used
providing that the air is filtered and lubricated to guarantee seal greasing
and corrosion protection. In the design stage it needs to be considered that
the rotation movement is obstructed by the seal friction.
This frictional drag is pressure dependant and must be considered for the
drive torque of the rotary table. Corresponding information can be found in
the relating diagrams which show the starting torques existing while all
junction levels are pressurised.
When placing an enquiry or an order, the operating circumstances should
be stated. These are for example operating pressure, medium, functionality
(single-acting od double-acting) and cycle time.