Machine Screw Jacks are the most widely used mechanical actuator for intermittent duty cycles as the actuator incorporates a precision worm gear set in a rugged casting delivering positive, precise actuation. The cubic design offers modern aesthetics and versatile mounting on two faces of the gearbox, while eliminating the need for upright and inverted variants. Available in a comprehensive range of materials and fittings resulting in over 140 million configurations to help you meet your specific application requirements. View our applications page for examples and further information.
Consider all application constraints then choose a product that looks suitable for the intended application. View our compare the range if you need help choosing which Screw Jack best meets your requirements then, calculate the power and torque requirements. This is a 5 step process:
'H' and 'U' configured jacking systems are typical and include screw jacks, bevel gearboxes, motor, reduction gearboxes, drive shafts, couplings and plummer blocks. Screw jack arrangements or configurations can be built in many formats with the use of bevel gearboxes which allow the direction of drive rotation to be selected on assembly. The gearboxes come in 2,3 and 4 way drive types. See Neeter Drive Bevel Gearboxes for more details.
1. Modifications to the standard screw jacks
This would include non-standard painting or plating of the housing, 2 or 3 start threaded lifting screws, stainless steel lifting screws or worm shafts, increased closed heights, extended worm shafts, opposite threading of lifting screws, etc.
2. Additions to the standard screw jacks
Items such as wear indicators, safety nuts, rotation monitoring kits, special lifting screw end fittings, encoder adapter flanges, etc.
3. Completely special screw jacks
Where a modification of our existing range is not practical we have the facilities to design and manufacture screw jacks tailored specifically to your requirements.
View some special design examples in applications
The screw jacks can be connected together in systems so that multiple units can be operated and controlled together. These jacking system arrangements or configurations can be built in many formats with the use of bevel gearboxes, motors, reduction gearboxes, drive shafts, couplings, plummer blocks and motion control devices. All of these items are available in the System Components section.
Two of the most popular system configurations are the 'H' and 'U' configured jacking systems. To see an example of each read the Example Jacking System Arrangement data sheet (PDF, 160Kb).
Remember that multiple screw jacks can be linked together mechanically or electrically. The latter is useful if there is no space for linking drive shafts. For more information refer to the Screw Jack Section (PDF, 4.1Mb) of the Power Jacks Design Guide.
If multiple machine screw jacks are connected in a mechanically linked system then the complete system may be considered self-locking. If you would like this checked consult Power Jacks. alternatively to be sure include a brake on the system either as a stand alone device or as a brake motor.