RfN 7012
For tight spaces and large transmissible forces
Ultra-narrow 4-piece version. Due to the clamping cones, there is no axial displacement. Self-releasing.
Extremely slim design, for applications where space is limited
Ultra-narrow 4-piece version. For tight spaces and large transmissible forces. Due to the clamping cones, there is no axial displacement
The defining feature of the RfN 7012 locking assembly is its ability to transmit large forces and moments reliably. Thanks to its extremely slim design, it is ideal for applications where the lack of space poses a real challenge.
In addition, the RfN 7012 is able to compensate for small tolerance errors and minor assembly errors, thereby simplifying installation and operation. Another useful feature of this locking assembly is its ability to self release during removal, which saves time and makes it easy to disassemble.
Overall, the RfN 7012 is an excellent solution for reliably transmitting large forces and moments in confined environments while ensuring efficient management of tolerances and assembly errors.
Benefits
- Extremely slim design, particularly suitable for applications where space is limited. The RfN 7012 locking assembly evens out small tolerance variations and compensates for minor assembly errors.
- Large transmissible forces and moments – several RfN 7012 locking assemblies can be arranged in series. The transmissible torques and axial forces are added together – please consult our technical experts in this regard.
- Bending moments and radial loads – combined loads can be transmitted.
- Easy mounting – RfN 7012 locking assemblies can cover large fit clearances.
- Low susceptibility to contamination – the functional surfaces are pressed firmly together when the clamping screws are tightened, thereby preventing the ingress of dirt and moisture.
- Wear-free – the RfN 7012 locking assembly operates without any moving parts on the shaft and hub, reliably preventing wear and play. This means it can be tightened and released multiple times.
Applications
- Sprockets
- Levers
- Belt pulleys
- Slip-on gears
- Belt drums
- Running wheels
- Rope pulleys
Locking assembly installation
The locking assemblies are supplied lightly oiled and ready for installation.
The values for T, Fax, pW and pN apply to the locking assemblies in their delivered condition.
Surface finishes
For shaft and hub bore Ra = 3.2 μm
Tolerances
We recommend the following installation tolerances:
Shaft: k9-h9; Hub: N9-H9
Max. permissible shaft: k11-h11; Max. permissible hub: N11-H11
However, to avoid excessive deformation of the relatively thick-walled thrust rings, the locking assembly should be arranged as symmetrically as possible between the shaft and hub bore. If the shaft is smaller than nominal dimension d, the bore should exceed nominal dimension D to the same extent (and vice versa). The radial run-out quality is determined by the direct centring between the shaft and hub.
Arrangement of several RfN 7012 locking assemblies
If several locking assemblies are to be installed, the transmission values from the table can be added together provided that the locking assemblies are located within a distance of 4·L.
Changing the screw tightening torques
The locking assemblies are generally equipped with grade 12.9 screws. A reduction is possible by lowering the screw tightening torque. The permissible lower limit is calculated by multiplying the TA values by 0.5. There is a proportional relationship between the values of T, TA , Fax, pW and pN.
Auxiliary thread
To facilitate removal, the front thrust rings have auxiliary threads.
