RfN 4161 stainless steel

The RfN 4161 stainless steel shrink discs represent the latest technology in clamping connections. Depending on the design, they essentially consist of one or two conical thrust rings and an inner ring. These are pressed against each other axially using clamping screws. The main difference, compared to internal clamping connections, is that the contact pressure is exerted on the hub from the outside. As a result, the shrink disc is not subjected to the main force; rather, the torque is transmitted frictionally at the joint surface between the shaft and hub without using an intermediate element. Consequently, a shrink disc represents a straightforward and cost-effective way of creating a force fit (shrink fit) for highly stressed shaft-hub connections. Previously, press fits could only be achieved with complicated calculations, extremely tight manufacturing tolerances and considerable effort during assembly and disassembly. In addition, these older solutions pose problems in the event of any necessary repairs (replaceability, adjustment, centring, etc.). No other type of shaft-hub connection offers anywhere near the same level of fatigue resistance under alternating torsional stresses or such exceptional radial run-out.

Product features

• Unlimited applications 
• Shrink discs are suitable for mounting hub bodies of any kind on shafts and axles. They can be used in place of shrink fits, wedge connections, keyway or polygonal connections, and splined shafts, among others. They provide a completely reliable means of securing gear wheels and sprockets, levers, cams, cam discs, belt pulleys, brake discs, flywheels, couplings, slip-on gears, flanges, rope pulleys and running wheels.
• Standard series – for high torques.
• Slitted inner ring – low loss forces and contact pressures exerted on shaft and hub.
• Maximum reliability – suitable for static, dynamic and impact loads.
• Simple manufacturing of components – only minimal requirements have to be met by the functional surfaces of the components being joined.
• Easily replaceable – the RINGFEDER shrink discs do not involve any kind of positive locking.
• Easy mounting – no steps, keyways or pins are required. Can be mounted at any point on the shaft using standard screws and commercially available tools. No additional machining or fitting work is required.
• Short assembly times – cost savings, especially in series production.
• Easy removal – after loosening the clamping screws, the RINGFEDER shrink disc will self release and the hub will move freely on the shaft.
• Low susceptibility to contamination – a longer service life, as the functional contact surfaces are pressed firmly together when the clamping screws are tightened, thereby preventing the ingress of dirt and moisture.

Surface finishes

For shaft diameter d_w: Peak-to-valley height: R_a ≤ 3.2 μm.