Screw jacks M-J are often, technical and economically, the optimal solution in applications that require precise and safe lineal movement to lift-lower, push-pull, tilt-pivot, lock-unlock...; mainly for medium-heavy loads and medium-low speeds.

Screw jacks combine a screw with a worm gear box and driven by an electric motor, convert rotation into linear motion.

In cases that so require, bellows protect the screw, making Screw jacks also suitable in outdoor or aggressive environments. Available materials and surface coatings allow to cover almost any environmental condition.

NIASA Screw jacks offer you a wide range of load capacities, from 5 to 500 kN (higher on request), tensile and compressive.

A large variety of options and accessories adapt Screw jacks to practically any system that may be designed, including drive (any type of electric motor), detection and control devices (limit switches, encoders, etc.)...

Safety nuts avoid that load falls in case of failure of the operation trapezoidal one, option advisable when a hypothetical failure may result into injuries for people or important damages for the machine.

CONFIGURATIONS

There are two Screw jack configurations:

• SR (round tube) & SS (square tube): The screw translates when the gear box input shaft turns. A rear tube protects the screw. Optionally, in version SS a nonrotation device avoids the screw rotation while moving.
• NU: The nut translates along the screw when it rotates, driven by the input shaft through the gear box.

In both configurations, you can choose between two kinds of precise screws:

• Trapezoidal (TR): These are a cost-efficient and an excellent option for many cases, especially with rough conditions.
• Ball (BA): These are more expensive, but have better performances, basically much lower power consumption and high accuracy, repeatability and efficiency. Can usually work under unlimited duty cycles at medium load speeds.

In the same way, two gear box ratios are possible: Normal and Low speed. In combination with different screw leads, motor speeds and additional reducers, make possible to get any movement speed you may need.

TRAPEZOIDAL vs BALL SCREW

COMPARISON OF TECHNOLOGIES

The main advantages of NIASA screw jacks against other systems, such as pneumatic and mainly hydraulic cylinders, are the following:

• Precision of movement and positioning.
• Safeness, due to their irreversibility in many configurations and/or by adding different braking devices.
• Energy efficiency, as their parts offer high/very high performance, especially with ball screws, low transmission ratios and high speeds.
• Easy and fast assembly, since hydraulic or pneumatic groups are not required, but just an electric motor.
• Reliability and durability, and less maintenance, due to the mechanical robustness and construction simplicity.
• Modular design.
• Multiple positions of operation.
• Easiness to obtain synchronized movements of several equipment, including under different loads.
• Low size for the same load capacity.
• Etc.

SAFETY NUT

If you require a safety nut, that avoids load falls in case of breakage of normal nut, see Option: SAFETY NUT.
They are available for all screw jacks sizes, configurations SR/SS and NU, only for trapezoidal screws.