RfN 7012 Locking Assembly

Slimmest Design for Confined Spaces

The slimmest, four-piece RfN 7012 locking assembly is ideal for applications with tight installation spaces while still requiring the transmission of high forces and torques. Its conical clamping surfaces prevent axial displacement during installation. Additionally, its self-releasing design ensures fast and trouble-free disassembly.

The compact geometry not only saves space, but also allows for multiple assemblies to be mounted in series, enabling the transmission values to be added. The RfN 7012 can also compensate for small tolerance deviations and installation errors, simplifying installation and enhancing operational reliability.

Advantages

• Slimmest construction – ideal for applications in confined installation spaces
• Compensates for minor tolerance variations and assembly misalignments
• High transferable torques and axial forces – multiple units can be arranged in series (consult technical support)
• Capable of transmitting combined bending and radial loads
• Easy to install – can bridge larger fitting clearances
• Low sensitivity to contamination – functional surfaces press tightly together during tightening
• Wear-free – no relative movement between hub and shaft, allowing multiple reuse without loss of performance

Applications

• Chain wheels
• Levers
• Belt pulleys
• Mounted gear units
• Conveyor drums
• Idler wheels
• Rope pulleys

Installation and Technical Notes

• Delivery condition: lightly oiled and ready to install
• Recommended surface roughness: Ra = 3.2 µm on shaft and bore
• Recommended fits:

• • Shaft: k9–h9
  • Hub: N9–H9
  • Max. permissible: shaft k11–h11; hub N11–H11

• To avoid deformation of the relatively thick pressure rings, it is recommended to install the unit symmetrically between shaft and hub bore.

Use of Multiple RfN 7012 Units

• Transmission values (torque and force) can be added when assemblies are spaced within 4·L of each other
• For accurate design, consult technical support

Adjustment of Tightening Torques

• Assemblies are equipped with grade 12.9 screws
• Tightening torque can be reduced to 50% of standard TA values
• Values for T, TA, Fax, pW, and pN vary proportionally

Ejector Threads

• Ejector threads are provided in the pressure rings for easy disassembly