Worm Gear electric ball screw jack, anti-Rotation and higher pitches available
Translating(traveling screw) and rotating (traveling nut) configurations
Move loads and apply force more efficiently than other machine screw actuators
No self-locking! 
Due to the lack of friction, a keeping brake is essential: a electric motor brake or a spring pressure brake is necessary.
These worm equipment screw jacks are extremely precision and reliability, it could meet all the necessary basic safety, cost-efficiency, and sturdiness mandates of the application. High power bronze worm gear is used, the payloads from 0.5T to 100T . A total of 11 sizes can be found, each in a touring nut version and a basic version.
The screw jacks can be used separately or in organizations linked with drive shafts, joints, couplings, bevel gearboxes and other mechanical components. In addition they can be driven by different motors: electrical, with either AC motor or DC motor in addition to hydraulic or Worm Gear Jack pneumatic motors. Each one of these motion control items can be built-in many type jacking program arrangements or configurations.
Ball screw jacks are common where higher speeds and duty cycles are needed. Most screw jacks make use of trapezoidal screws Tr, because they are simple, robust and inexpensive. The proportion of screw jacks that use ball screws is however constantly increasing. The reasons for this are mainly their pitch accuracy, their high efficiency (less power consumption and less heat generation) and the higher pitches offered, which permit higher stroke speeds.
A screw jack can add a machine cut lifting nut. For this model screw jack, only the bronze nut move combined with the screw shaft. The lifting screw will not slide. It is definitely like the linear actuator working principle which converts rotational movement into linear motion. From this point to understand, a power linear actuator is definitely a motorized screw jack.
The screw thread of screw jack can be acme screw and ball screw. So there are few variations of the screw jack. Commonly, machine screw jack and ball screw jack can be found in your engineer task. Weighed against acme screw, the ball screw is definitely more efficient as there are ball bearings between the nut and screw. The anti-friction ball bearing can increase the ball screw efficiency.