RfN 7012 locking assembly for bending moments

Suitable for applications in confined spaces
The RfN 7012 locking assembly is distinguished by its ability to reliably transmit high forces and torques. Thanks to its extremely slim design, it is especially well suited for applications with tight installation spaces where space is limited.

In addition, the RfN 7012 can compensate for small tolerance deviations and minor installation errors, which simplifies both installation and operation. Another practical feature is its self-releasing function during disassembly, allowing for a quick and effortless removal.

Overall, the RfN 7012 is an excellent solution for reliably transmitting large forces and torques in confined environments, while offering efficient tolerance and assembly error compensation.

Product Features

• Slimmest design, ideal for applications with restricted space. The RfN 7012 compensates for small tolerance variations and minor installation errors.
• High transmissible forces and torques – multiple RfN 7012 units can be arranged in series. The transmissible torques and axial forces are additive – please consult our technical experts for this.
• Bending moments and radial loads – combined loads can be transmitted.
• Easy assembly – RfN 7012 units can bridge large fitting gaps.
• Low sensitivity to contamination – during bolt tightening, the functional surfaces press tightly together, preventing dirt and moisture from penetrating.
• Wear-free operation – the RfN 7012 operates without moving parts on shaft and hub, reliably preventing wear and backlash. It can be repeatedly tightened and released.

Applications

• Sprockets
• Levers
• Belt pulleys
• Shaft-mounted gear units
• Conveyor drums
• Running wheels
• Rope sheaves

Installation Instructions

• Locking assemblies are delivered lightly oiled and ready for installation.
• Values for T, Fax, pW, and pN apply in delivery condition.

Surface Finish

• Shaft and hub bore: Ra = 3.2 µm

Recommended Tolerances

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

To avoid excessive deformation of the relatively thick-walled pressure rings, the locking assembly should be arranged as symmetrically as possible between the shaft and the hub bore. If the shaft is smaller than the nominal diameter d, the bore should be larger than nominal diameter D by the same amount, and vice versa. Runout quality is determined by the direct centering between shaft and hub.

Arrangement of Multiple RfN 7012 Units

• If multiple assemblies are used, transmission values can be added if the units are placed within a distance of 4·L from each other.

Adjustment of Bolt Tightening Torques

• The assemblies are equipped with bolts of grade 12.9.
• Reduced tightening torque is allowed. The minimum permissible torque is TA × 0.5.
• T, TA, Fax, pW, and pN values are proportionally related.

Ejector Threads

• For easier disassembly, ejector threads are provided in the front pressure rings.