CUBIC SCREW JACK VS. BEVEL GEAR SCREW JACK

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CUBIC SCREW JACK VS. BEVEL GEAR SCREW JACK Powered By Docstoc
					    CUBIC SCREW JACK                            VS. BEVEL GEAR SCREW JACK
    Which is right for your application?


    What are your operating parameters?

              Load ..................................................The weight or force applied to the system

              Orientation .....................................The relative position or direction in which the force is applied

              Speed     ...............................................How fast the screw jack lifts the load

              Travel    ...............................................The distance or range of motion

              Voltage     ............................................The AC or DC motor needed to operate the actuator

              Precision      ........................................Travel accuracy, positioning accuracy, repeatability, accuracy of
                                                                     the return position at the end of a stroke

              Environment          .................................The surrounding conditions in which the system will operate

              Duty Cycle ......................................The amount of time the screw jack operates in an hour

                                                            STEP ONE
                                         Choose the type of Cubic Screw Jack

    Cubic Screw Jack Features & Benefits
          Versatile Mounting - Unit can be mounted upright or inverted
          Acme and Ball Screw models are available
          Translating screw (type 1) and rotating screw (type 2) models are available
          Clean surface - easy to maintain in dirty environments
          Contemporary design for improved aesthetics
          Fast delivery - selected models are in stock
          German Engineering


    Bevel Gear Screw Jack Features & Benefits
          Speed - 4 times faster than “Classic Screw Jacks”
          Versatile Mounting - Unit can be mounted upright or inverted
          Acme and Ball Screw models are available
          Translating screw (type 1) and rotating screw (type 2) models are available
          Can eliminate miter gearbox
          Contemporary design for improved aesthetics
          Fast delivery - selected models are in stock
          German Engineering
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                                               STEP TWO
                     Calculate the input power (kW) needed for your application

Find a Cubic Screw Jack model with a capacity greater then the actuator load. Go to the applicable Cubic
Screw Jack Performance Table and find Travel per Worm Turn and Worm Torque at Full load.


                                                        Actuator Load (kN) x Worm Torque at Full Load (Nm)
                              Actuator Torque (Nm) =
                                                                    Actuator Capacity (kN)

Calculate the desired input RPM;
                                                                    Desired Lift Speed (mm/min)
                                Actuator Input RPM =
                                                                    Travel per Worm Turn (mm)

Calculate the actuator input power;
                                                            Actuator Torque (Nm) x Actuator Input RPM
                         Actuator Input Power (kW) =
                                                                                9549



Compare required input power to maximum power per screw jack shown in the performance table. If the
required power exceeds this number, the lifting speed should be reduced or a larger screw jack should be
selected that will meet the input power requirements.


For Cubic Screw Jack performance data, see page 7


If using a gear reducer, motor power must be multiplied by reducer efficiency to obtain reducer output (screw
jack input) power.




                                             STEP THREE
For Bevel Gear Screw Jack performance data, see page 19


Multiple screw jack arrangements driven by a single motor. Sum the input power requirements of all Screw
Jacks. If you are using mitre gear boxes, allow for 2% power loss through each 90º turn in the power path.




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