hydraulik - Jahns-Regulatoren

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1.9 Torque Tiso = limit torque Transmittable torque of the gearbox, with continuous operation, calculated in accordance to ISO DP6336 for gears and safety factor of 1. This torque corresponds to a life duration equal to 50.106 cycles of the most stressed element (theoretically considered unlimited by the ISO DP6336; horizontal curve in the Wöhler fatigue diagram). This torque does not represent a duration, but it is useful for a quick selection of the maximum size of the gearbox. Tcont = continuous torque Transmittable torque of the gearbox, with continuous operation, that guarantees a duration of ‘h’ hours, with a gearbox output rotation velocity of ‘n2’ RPM. Tcont is expressed as a function of the product n2 h. Teq = equivalent torque Teq represents the value of a constant torque which determines the same duration in hours of the torque induced by the work cycle. Known as T21 … T2n the torque transmitted by the gearbox at the output velocity n2i for a time duration in hours of hi, the equivalent torque is: where Timp = impulsive torque value of the static torque or an istantaneous peak load that the gearbox can withstand. 1.10 Effi ciency ηm = mechanical effi ciency: ratio between the output power and input power; normally it is considered to be equal to 0,97 – 0,98 per reduction stage that makes up the gearbox; it depends upon various factors, of which velocity, torque, ratio, working position and lubrication. 2. Gearbox selection method 2.1 Selection Once established the selection criteria, which can be defi ned using an ISO or AGMA safety factor, based upon the class according to the F.E.M. standard or by expressing a minimum life duration, the equivalent output torque Teq is determined as well as the required duration and the reduction ratio. Using these criteria the gearbox is selected. - safety factor ISO/AGMA: the gearbox must garantee the requested theoretical lifetime; - F.E.M. class: the gearbox must garanteee that the requested theoretical lifetime correspond to that indicated by the F.E.M. class as a function of the max and Teq; - life duration: the gearbox must have a life duration greater than that required as a function of Teq. For example, table... on page F.2 / F.9 shows the continuous torques as a function of gearbox size and the reduction ratio. Please note that when an electric motor is used, the start up torque can be 2.5 times greater than its nominal value. H Y D R A U L I K Page B. 8 www.jahns-hydraulik.de
For the correct value please refer to the electric motor supplier’s catalogue (classes CEI 2–3/IEC34-1). The start up torque must not exceed the gearboxes maximum torque. The number of start-up per hour and the hours of operation per day must be carefully considered. If the output velocity is constantly less than 1 rpm, there may be problems with the lubrication of the output stage, which could reduce the calculated theoretical life. In this case it is advised that you contact the Jahns personnel for a proper selection. class Jahns waives all responsability of improper use of the selection criteria mentioned above, in particular for all applications subject to special rules and regulations (for example when personal safety is involved) and places this responsability on the application constructor. It is recommended that the constructor contact Jahns technical department for all such technical support. 2.2 Verifi cations Gearbox output support: For each gearbox the dynamic radial loads according to ISO 281 for a duration of L10 corresponding to n2 h = 100.000 are shown in the diagrams. For different durations, applicable radial loads can be obtained by multiplying the values in the diagrams by the correction factor kf. With regards to eventual axial loads, one must ensure that they do not exceed the maximum allowed values. www.jahns-hydraulik.de duration with Teq
Page 1 and 2: H Y D R A U L I K Planetary Gearbox
Page 3 and 4: General information The new range o
Page 5 and 6: www.jahns-hydraulik.de Page B. 5 H
Page 7: Example: duration necessary in hour
Page 11 and 12: 4. Negative brakes 4.1 Negative bra
Page 13 and 14: ST BB B3 0 BS www.jahns-hydraulik.d
Page 15 and 16: 7.2 Lubrication The gearboxes are s
Page 17 and 18: Symbol Unit Description Fr 2 N Outp

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