Contents
What types of Screw Jacks are there?
Basics
Are you looking for precise and high-performance solutions for lift and positioning movements? Then screw jacks are the ideal choice for you. However, there are different types of screw jacks, each addressing specific needs. Discover below a comprehensive overview of all screw jacks.
1. What are screw jacks?
Screw jacks are true all-rounders in drive technology. We have been manufacturing screw jacks since 1945. The basic principle is simple and brilliant at the same time: a rotary motion is easily converted into an axial motion – and that in the smallest of spaces.
Here's how it works: an electric motor drives a worm shaft, which sets a worm wheel in rotary motion. The worm wheel is equipped with a threaded spindle (standard: trapezoidal thread; special version: ball screw) – and the screw jack is complete.
2. You have the choice: 4 types of gearboxes are available
Which type of screw jack is right for your application depends on various factors: the required load capacity, the load case, and the available space. Each screw jack is generally available in two versions:
Basic Version
The lifting spindle performs the linear movement.
Traveling Nut Version
The traveling nut carries out the linear movement.
We cover this wide load range with our proven screw jacks: 0.5 kN to 2,000 kN.
3. An overview of screw jack types
Cubic Screw Jack - from 2.5 kN to 500 kN
The housing shape is already in the name: it's cubic, like a cube. All surfaces of this design offer many mounting options for various constructions. We can achieve load capacities from 2.5 kN to 500 kN and offer many customization options.
The cubic screw jacks are designated MJ or BJ. In total, 11 standard sizes are available.
Classic Screw Jacks - from 0.5 kN to 2000 kN
The housing shape of these screw jacks is already in the name: classic. Unlike the cubic design, the screw jacks in this series can handle higher loads up to 2000 kN. Due to their design, you cannot attach construction elements to the housing.
The classic screw jacks are designated MC. There are 14 sizes available, with each size also offered in traveling nut and base versions.
High-Performance Screw Jacks HMC - from 5 kN to 1000 kN
The name already indicates what’s inside the gear. These high-performance screw jacks are tailored for special dynamic and demanding applications, for which standard screw jacks are unsuitable due to their simple structural design.
The result: we can achieve higher speeds and loads. The high-performance screw jacks are designated HMC. They can lift loads from 5 kN to 1000 kN.
High-Speed Screw Jacks KH - from 15 kN to 90 kN
The GROB high-speed screw jacks complement our screw jack program by extending the range of applications. Unlike standard screw jacks, bevel gear transmissions are used.
The range includes three sizes with gear ratios of 1:1, 2:1, and 3:1. Thanks to the favorable efficiency of the bevel gear sets, the overall efficiency of the GROB high-speed screw jacks is approximately 75% with ball screw spindles and around 40% with trapezoidal screw spindles.
This is what a screw jack looks like inside
GROB Antriebstechnik GmbH
4. Pros and Cons
Cons
✘ Speed Limitation: In many cases, screw jacks are slower than other motion systems, which can be problematic in high- speed applications.
✘ Complexity: The design and installation of screw jacks can be complex and often require specialized knowledge.
✘ Maintenance Requirements: Screw jacks require regular maintenance to ensure optimal performance and longevity.
✘ Cost: High-quality screw jacks can be expensive, especially if they are customized.
Pros
✔ Precise Motion Control: Screw jacks allow for precise control of linear movement, which is crucial in applications where accuracy is important.
✔ High Load Capacity: Screw jacks can lift or move heavy loads, making them ideal for high-load applications.
✔ Energy Efficiency: They can manage energy transfer efficiently, resulting in energy savings and lower operating costs.
✔ Versatility: Various types of screw jacks, such as spindle screw jacks, worm gear jacks, and high-speed screw jacks, are suitable for different applications.
✔ Long Service Life: Well-maintained screw jacks can have a long service life, making them cost-effective.
Where screw jacks have already been successfully used
More applications with screw jacks can be found here:
Want to know more?
10 steps to the right Screw Jack
Choosing the right screw jack doesn’t have to be a guessing game. With our step-by-step guide, you can quickly and confidently select the ideal model for your application – simple and actionable.