FLENDER gear units - DS TECH

© Siemens AG 2011Selection of the gear unitsGuidelines for selection■ OverviewFor driven machines with constant speeds and variable powerratings the gear unit can be designed according to the equivalentpower rating. For this a working cycle where phases I, II ...n require power P I , P II ... P n and the respective power ratingsoperate for time fractions X I , X II ...X n is taken as a basis. Theequivalent power rating can be calculated from these specificationswith the following formula:6.6 X I X IIP 2eq = P 6.6 + PI II6.6 + ... P 6.6n100 100The size of the gear unit can then be determined analogously topoints 1.1 ... 1.5 and 3.The following applies:X n100Variable power ratingIf any one of the three requirements is not met, P 2eq must berecalculated.It must be borne in mind that a brief peak power rating notincluded in the calculation of P 2eq must not be greater thanP max = 1.5 x P 2N .In applications where the torque is variable but the speedconstant, the gear unit can be designed on the basis of theso called equivalent torque.For specific applications, a gear unit design which is finite-lifefatigue-resistant can be sufficient. This includes, for example,sporadic operation (e.g. lockgate drives).Example: Service classification3P 2N ≥ P 2eq f 1 f 2PP 2eqThen, when P 2N has been determined, the power and timefractions must be checked by applying the following requirements:• The individual power fractions P I , P II … P n must be greaterthan 0.4 x P 2N .• The individual power fractions P I , P II ... P n must not exceed1.4 x P 2N .• If power fractions P I , P II ... P n are greater than P 2N , the sum oftime fractions X I , X II … X n must not exceed 10 %.X l=15%P lIP llP lll PlVII III IVX lI=30% X lII=40%X=100%G_MD30_EN_00043XX lV=15%1275 Newton, local 15Boucherville, Qc,Canada, J4B 5H2In the case of a service classification, it is necessary toconsult Siemens.(450) 655-7447info@pt-dstech.comwww.dstech.caSiemens MD 31.1 · 20113/3