Ringfeder Gear Coupling TNZ ZCAK ZCBK
TNZ series ZCAK and ZCBK gear couplings with limited end float for precise axial shaft positioning and controlled drivetrain alignment
The Ringfeder TNZ ZCAK and Ringfeder TNZ ZCBK are torsionally rigid twin cardanic gear couplings with limitation of end float.
The limitation of end float serves to axially locate a shaft mounted on sleeve bearings. The rotor of an electric motor with sleeve bearings can therefore be aligned within a defined tolerance range via the coupling to the bearing of the driven machine, ensuring that the rotor remains at its magnetic centre during acceleration of the driving machine.
The limitation of end float restricts the ability to compensate for angular and radial shaft misalignments. Compared to the TNZ ZCAK with integrated O-ring, the TNZ ZCBK is equipped with screwed-on separate O-ring supports.
The coupling features straight internal teeth and hubs with crowned external teeth, allowing compensation for angular, radial and axial shaft misalignment. Standard tooth geometry accommodates angular misalignment of up to 0.5° per toothing plane, with axial movement of several millimetres, while radial displacement depends on the distance between the two toothing planes. Manufactured from forged steel with a minimum apparent yield strength of 335 N/mm², the coupling incorporates high-quality tooth profiles and ultra-high-pressure grease to minimise restoring forces and support a long service life. Synthetic rubber O-rings provide sealing, with the coupling sleeves secured by fitted bolts and self-locking nuts. Alternative tooth geometries and materials are available for specialised applications, and with special seals, operating temperatures of up to +120°C can be achieved.
Features
- Torsionally rigid gear coupling manufactured from high-quality steel
- Compact design providing high power density
- Compensates for angular, radial and axial shaft misalignment
- Suitable for operating temperatures up to +120°C when fitted with special seals
- Available with split sleeve (ZCA / ZCB, with the ZCA range also available in ZCB design) or single-piece sleeve (ZCH)
- Elastic O-ring can be replaced without moving the coupled machines
- Bore sizes up to 270 mm
- Nominal torque up to TKn = 195,000 Nm and maximum torque up to TKmax = 390,000 Nm
- Maximum operating speed up to 6,000 rpm




Product Specifications
| CAD | Size | Identifier ZCA | TKN Nm | nmax 1/min | d3kmin mm | d3kmax mm | D1 mm | D6 mm | L mm | Gwsb kg |
|---|---|---|---|---|---|---|---|---|---|---|
| 69 | XC2706 | 1750 | 6000 | 12 | 50 | 111 | 81,5 | 89 | 4,0 | |
| 85 | XC2708 | 2750 | 4600 | 18 | 60 | 152 | 103,5 | 103 | 8,4 | |
| 107 | XC2710 | 5500 | 4200 | 28 | 75 | 178 | 127,5 | 127 | 14,1 | |
| 133 | XC2713 | 8500 | 4000 | 40 | 95 | 213 | 156 | 157 | 24,8 | |
| 152 | XC2715 | 13500 | 3850 | 50 | 110 | 240 | 181 | 185 | 36,4 | |
| 179 | XC2717 | 22000 | 3700 | 60 | 130 | 280 | 209 | 216 | 58,0 | |
| 209 | XC2720 | 35000 | 3200 | 70 | 155 | 318 | 245,5 | 245 | 87,0 | |
| 234 | XC2723 | 43000 | 2900 | 85 | 170 | 346 | 274 | 278 | 113,7 | |
| 254 | XC2725 | 68000 | 2600 | 95 | 190 | 389 | 307 | 308 | 163,1 | |
| 279 | XC2727 | 82000 | 2300 | 110 | 210 | 425 | 334,5 | 358 | 215,4 | |
| 305 | XC2730 | 150000 | 2100 | 120 | 230 | 457 | 366 | 388 | 261,5 | |
| 355 | XC2735 | 195000 | 1800 | 130 | 270 | 527 | 423 | 450 | 409,2 |
