Power Jacks E-Series - Machine - Manual (Page 20)

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Operation
5
5.2.28 Connecting Screw Jacks in Series
The number of screw jacks that can be connected in series is limited by input torque
requirements on the first worm shaft in the line. For the E-Series the torque on the worm shaft
of the first screw jack should not exceed 300% of its rated full load torque (this does not include
the 200kN screw jacks which are rated at 200%).
5.2.29 Efficiency of a Multiple Screw Jack System
In addition to individual device efficiencies, the efficiency of the screw jack arrangement must
be taken into consideration. The arrangement efficiency allows for misalignment due to slight
deformation of the structure under load, for the losses in couplings, bearings, and for a normal
amount of misalignment in positioning the screw jacks and gearboxes. For efficiency values
consult Power Jacks product literature or engineers.
5.2.30 Screw Jack Fitted with 3rd Party Accessories
If your screw jack is fitted with a device not manufactured by Power Jacks then please consult
the provided manual for this device.