FLENDER Standard Couplings Highly Flexible Couplings — ELPEX-S Series © Siemens AG 2015 General information ■ Overview Coupling suitable for use in potentially explosive atmospheres. Complies with the current ATEX Directive for: II 2 G T3 D160 °C X (Type EST is not available in Ex version.) II 2 G T4 D120 °C X ELPEX-S couplings are highly torsionally flexible and because of their low torsional stiffness and damping capacity are especially suitable for coupling machines with a highly non uniform torque pattern. Standard ELPEX-S coupling types are designed as flange-shaft- connections or shaft-shaft connections. Application-related types can be implemented on request.
■ Benefits The ELPEX-S coupling is suitable for horizontal and vertical mounting positions or mounting at any required angle. The cou- pling parts can be arranged as required on the shafts to be con- nected. There are 4 different rubber element versions with different grades of torsional stiffness available for each size from stock. On certain types the flexible rings can be changed without hav- ing to move the coupled machines. ELPEX-S couplings are especially suitable for reversing opera- tion or operation with changing directions of load.
If substantial overload occurs, the rubber disk element of the coupling is irreparably damaged, the coupling throws the load and thus limits the overload for particular operating conditions. The coupling can be inserted and fitted blind e.g. in a bell hous- ing. The rubber disk elements are fitted virtually without backlash and give the coupling linear torsional stiffness, i.e. the torsion stiffness remains constant even when the load on the coupling increases. There are outer flanges with different connection dimensions available for each coupling size. ■ Application The ELPEX-S coupling is available as a catalog standard in 12 sizes with rated torques of between 330 Nm and 63000 Nm.
The ELPEX-S coupling is frequently used for diesel motor drives or reciprocating compressor drives. Because the different rub- ber versions enable the torsional stiffness to be adjusted to meet requirements, the coupling is also suitable for drives which re- quire a specific and preferably precalculated torsional vibration behavior setting. The coupling is suitable for ambient temperatures of between -40 °C and +120 °C. 11 ■ Design The rubber disk element is vulcanized onto a flange on the in- side diameter. The flange can mount e.g. a Taper clamping bush or a hub. On its outer diameter the rubber disk element has driv- ing teeth, which are inserted into the outer flange.
The torque is transmitted positively between the rubber disk element and the outer flange. Elastomer materials of the rubber disk element Natural-synthetic rubber mixture 50 ° … 55 ° WN -40 °C … +80 °C Natural-synthetic rubber mixture 60 ° … 65 ° NN -40 °C … +80 °C Natural-synthetic rubber mixture 70 ° … 75 ° SN -40 °C … +80 °C Silicone rubber 55 ° … 65 ° NX -40 °C … +120 °C In the type for shaft-shaft connection the outer flange is screwed to a flange hub mounted on a machine shaft.
Materials Rubber disk element Grey cast iron EN-GJL-250/elastomer ELPEX-S coupling types ESN Coupling with hub, long or short version ESD Coupling with hub, with two rubber disk elements ESNR Coupling with hub, rubber disk element radially dismountable ESDR Coupling with hub with two rubber disk elements; rubber disk elements radially dismountable ESNW Coupling designed as a shaft-shaft connection with a rubber disk element; rubber disk element radially dismountable ESDW Coupling designed as a shaft-shaft connection with two rubber disk elements; rubber disk element radially dismountable EST Coupling suitable for mounting a Taper clamping bush Spheroidal graphite cast iron EN-GJL-400/elastomer Hubs, part 1, part 2 Steel Steel Outer flange Cast aluminum AlZnSi108..
Sizes 680 and 770 of spheroidal graphite cast iron EN-GJS-500 Cast aluminum AlZnSi108.. Sizes 680 and 770 of spheroidal graphite cast iron EN-GJS-500 11/2 Siemens MD 10.1 · 2015 Material / description Hardness ShoreA Iden- tifica- tion Ambient temperature Type Description Type EST Types ESN. and ESD.