“GIFLEX ” GE-T PRECISION RANGE - Moves

1 CHIARAVALLI Trasmissioni spa GIFLEX GE-T PRECISION RANGECOUPLINGTYPEMass in rangeFinishedbore dTaperLockBushHubs EFMNS cm2 HubsB1(1)(2)GE-T28-38 (1) Assembly distances(2) Coupling inertia moment with hubs I and E max. bore Code interpretationExample:GE-T 28I - 38E= with hub I + hub EGE-T 28I - 28I= with 2 hubs IGE-T 38E - 38E= with 2 hubs EEXECUTION WITH TAPER-LOCK BUSHDIMENSIONSM aterial: G25 CAST IRON MEASUREMENTS - WEIGHTS205 HUB IHUB ECHIARAVALLI Trasmissioni spa204 GIFLEX GE-T PRECISION RANGEM aterial: G25 CAST IRON * STEELCOUPLINGTYPEMass in rangeWITHOUTBOREF inishedbore dHubBHubAFlexibleComponentCD E +B(3)(1)(2)DIMENSIONS(1) Assembly distances(2) Coupling inertia moment with hubs A-B and max.

2 Bore (3) On request:Finished bore in compliance with ISO standards, H7 tolerance, keyway DIN 6885, sheet 1, JS9 tolerance. Dowel characteristic size of the coupling is defined by the maximum bore interpretationExample:GE-T 19A - 24B= with hub A +hub BGE-T 19A - 19A= with 2 hubs AGE-T 24B - 24B= with 2 hubs BGE-T 19A-24B* 1590 MEASUREMENTS - WEIGHTSCHIARAVALLIT rasmissionispa GIFLEX GE-T COUPLINGS with FLEXIBLE SPIDERTORSIONAL FLEXIBLE COUPLINGSPRECISE EXECUTIONINTRODUCTIONF lexible torsion couplings, which are connecting devices betweenrotating shafts, are designed to ensure shock-free torque transmis-sion and to compensate minor alignment deviations in operationbetween the shafts in industrial GE-T RANGE of flexible couplings ensures this level of perfor-mance and also provides excellent quality thanks to the machiningaccuracy and the choice of the materials general level of reliability provided by the GE-T couplings isensured by a satisfactory useful working life of the GE-T RANGE of flexible couplings represents torsionally flexible.

3 Mechanical couplings capable of transmitting a twisting momentproportional to the flexible yield of the intermediate couplings must also be capable of effectively absorbing possi-ble torsional vibrations due to the load or self-induced, to attenua-te impacts and torque peaks during the start-up phase and to com-pensate minor angular and parallel misalignments between theshafts, however ensuring an acceptable useful working features and more in general the performance required fromthe coupling depend almost exclusively on the quality of theintermediate component. The choice of the material usedto manufacture the coupling is therefore fundamen-tal. The curve that expresses the flexible charac-teristic of the intermediate component musthave a progressive trend (yielding at lowtorque values and remaining rigid athigher torque values) to ensure ope-ration without jerks at start-upand with a limited torsionalyield at steady state is essential for the inter-mediate component tohave a certain flexiblehysteresis, proportionalto the required absor-bing effect that ensuresthe coupling can effi-197 HUB BHUB ACHIARAVALLIT rasmissionispa GIFLEX GE-T FLEXIBLE COUPLINGS198ciently absorb possible torsional oscillations.

4 Furthermore, the use-ful working life of the coupling depends on the flexible yield of thematerial comprising the intermediary component. The physicalcharacteristics as described above are frequently in contrast witheach other and compared with other basic mechanical and tech-nological parameters. The performance of the intermediary com-ponent therefore cannot be adapted to the variety of operatingconditions when only one type of material is used and therefore thematerials adopted for the flexible ring gear must be selected thermoplastic elastomer is selected to meet medium levelneeds in the basic execution. This refers to an elastomer withmedium rigidity, characterised by an optimum internal dampeningeffect, resistant to ageing, to fatigue, to abrasion, as well ashydrolysis and to the principal chemical agents with special refe-rence to oils and ozone.

5 Operating temperatures lying between 40 C and +125 C with brief peaks of up to 150 C are permittedin the case of couplings in the base execution. Alternative mixescapable of meeting every practical need have been designed andare available on request for use in extremely demanding operatingconditions, or for needs that exceed average requirements. OPERATING AND ASSEMBLY CONDITIONSO peration of the flexible torsion couplings, such as the GE-T typeor similar couplings is characterised by a proportional featurebetween the twisting torque and the torsion angle and by the abi-lity to compensate limited angular and radial features of equal importance, but which are more difficult tointerpret are represented by the absorbing factor and the naturalfrequency or resonance.

6 To qualify its couplings, CHIARAVALLIT rasmissioni spadeclares permitted twisting torque values correla-ted to well defined torsion angle values, which has the limitingvalue of 5 corresponding to the maximum torque value. This pro-vides a valid guide for the progressive characteristic of the flexiblecurve. The maximum permitted values are shown in the case of theangular and radial misalignments, with the warning that theserefer to extreme values that cannot be added together (only angu-lar compensation or only radial compensation) and apply to"standard" operating conditions characterised by thefollowing: operating torque not exceeding the nomi-nal torque, a rotating speed of less than 1, and coupling temperature not excee-ding 40 C.

7 The maximum rotating speedexpressed in that corresponds toa maximum peripheral speed of 30m/sec. is indicated for each cou-pling of the GE-T RANGE . Thisspeed can be achieved with asufficient safety margincompared to the dangerof failure due to centrifu-gal force stress thanks tothe characteristics of thematerial used. Class dynamic balancingincompliance with ISOCHIARAVALLIT rasmissionispa GIFLEX GE-T FLEXIBLE COUPLINGS1991940 is recommended despite the fact that the half-couplings arefully machined on both external surfaces, if the actual operatingspeed exceeds SELECTION AND SIZING CRITERIAC ouplings are sized on the basis of the physical laws of mecha-nics and the resistance of the materials and also complies with theprovisions established in the DIN 740 standards Sheet coupling is selected on the basis of the criteria, which establi-shes that the maximum permitted stress is never exceeded even inthe most demanding operating conditions.

8 It follows that the nomi-nal torque declared for the coupling must be compared with areference torque that takes into account the overloads due to theway the load is exerted and the operating conditions. The refe-rence torque is obtained by multiplying the operating torque by aseries of multiplying factors depending on the nature of the loador on the ambient temperature : TKN = coupling maximum torque (Nm)TK max = coupling maximum torque (Nm)TKw = torque with coupling inversion (Nm)TLN = driven side operating torque (Nm)TLs = driven side static torque (Nm)TAs = motor side static torque (Nm)Ts = plant static torque (Nm)PLn = driven side operating power (kW)nLn = driven side rotating speed ( )

9 St = temperature factorSA = motor side impact factorSL = driven side impact factorSz = start-up factorMA = control side mass factorML = driven side mass factorLOAD DUE TO NOMINAL TORQUEThe permitted nominal coupling torque TKN mustapply for any operating temperature valueequal to or greater than the driven sideoperating torque = 9549 [Nm]The following condition mustbe satisfied, where Strepresents the temperatu-re factor, to take intoaccount overloads dueto the operating tem-perature for the = > TLN * StJLJA+JLJAJA+JL( PLn ) nLnCHIARAVALLIT rasmissionispa GIFLEX GE-T FLEXIBLE COUPLINGSSTART-UP LOADThe drive motor delivers a drive torque during the start-up transientperiod, which is a multiple of the nominal torque and depends onthe way the masses are distributed.

10 A similar situation occurs in thebraking phase therefore, these two phases are characterised bytorque impacts that have an intensity which depends on the distri-bution of the masses on the drive side MA and on the driven sideML, as well as the frequency of the number of start-ups on whichthe start-up factor Sz depends. The static torques for the drive sideand the driven side are expressed by the following relationships:- drive sideTS = TAS *MA *SA- driven sideTS = TLS *MM *SLMA and ML are assumed to be equal to 1, to a first approxima-tion, and if the distribution of the masses is unknown. The SA fac-tor can be assumed as being equal to the relationship between thestart-up torque and the nominal torque in the case of drives basedon an electric CAUSED BY TORQUE IMPACTSThe permitted nominal coupling torque TKN max must be equal toor greater than the start-up torque increased by the temperaturefactor and by St and by the start-up factor Sz for any operatingtemperature value.