FLENDER Standard Couplings Torsionally Rigid Gear Couplings — ZAPEX ZW Series © Siemens AG 2015 General information ■ Overview Coupling suitable for use in potentially explosive atmospheres. Complies with the current ATEX Directive for: II 2 GD c 120 °C (T4) -20 °C ≤ T a ≤ +80 °C 4 I M2 ■ Benefits ZAPEX gear couplings link machine shafts and compensate for shaft misalignment with weak restorative forces. High transmis- sible torque combined with compactness and light weight are characteristic of ZAPEX couplings. ZAPEX coupling types are constructed on a modular principle. This means that application-specific solutions can be delivered quickly. ZAPEX couplings require very little maintenance.
Regu- lar grease or oil changes at the prescribed intervals prolongs the service life of the coupling. ■ Application ZAPEX couplings are especially suited for operation in harsh op- erating conditions, such as drives in the iron smelting or cement industry. ZAPEX couplings are suitable for reverse operation and horizontal mounting positions and, in the case of type ZWNV, for vertical mounting positions. ■ Design A ZAPEX coupling comprises two hub sections with external teeth which are mounted on the machine shafts. Each set of ex- ternal teeth engages in a flanged socket with mating internal teeth. The flanged sleeves are connected via two flanges with close-fitting bolts.
ZAPEX ZW gear coupling types ZWN Standard type ZZS with adapter ZZW with intermediate shaft ZWH with coupling sleeve ZWBT with offset brake disk ZWBG with straight brake disk ZWB with brake drum ZWTR for rope drums ZBR with shear pins ZWS Clutch ZWNV Vertical type ZWSE Simple clutch-coupling combination The teeth are lubricated with oil or grease. On the ZAPEX type ZW, DUO sealing rings are used to seal the tooth space. The DUO sealing rings prevent the lubricant from escaping and dirt from entering the tooth space. The parallel keyways must be sealed during assembly to prevent lubricant from escaping. Customized hub designs are described after the types.
Further application-related coupling types are available. Dimen- sion sheets for and information on these are available on re- quest. ■ Function The torque is transmitted through the coupling teeth. The teeth are crowned, so angular displacement per tooth plane is possi- ble. Radial displacement can be compensated for via the space VA between the tooth planes. The internal teeth of the flanged sleeves are significantly wider than the external teeth of the hub parts, permitting a relatively high axial misalignment. A small angular misalignment on the coupling teeth results in an advantageous distribution of the lubricant film and a very low wear rate.
This favorable condition can be deliberately set by aligning the drive with the machine shafts with a slight radial mis- alignment. 4/2 Siemens MD 10.1 · 2015 Type Description