Screw Jack Application
Screw Jacks are the ideal product to push, pull, lift, lower and position object loads. They are essential components in automated machinery because of high reliability and synchronization. They usually operate in high-load applications. Additionally, screw jack is increasingly finding uses as alternatives to conventionally pneumatic and hydraulic systems, because it has better energy efficiency and greater levels of precision. Nuodun screw jacks and lifting systems offer wide-ranging lifting and positioning solutions for diverse industries.
Mechanical Advantage of Screw Jack
Our screw jacks can offer a better solution for high load application(10kN to 1200KN), improved performance and safety at lower costs is our unique advantage. What’s the mechanical advantage of screw jack compared with hydraulic systems?
- Better energy efficiency.
- Greater levels of precision.
- Environmentally Friendly since no high-pressure oil leaks.
- Increased Safety. In the event of power loss, screw jacks can be self-locking.
- More quicker and simple to install, program and tune.
- Reduced cost since no need ancillary hydraulic equipment, no hydraulic oil to maintain, no leaks to repair.
Which type of screw jack should you choose?
In order to know if a screw jack or screw jack system could be a solution for your application, you will need to consider which type of screw jack to select. There are worm gear screw jacks, bevel gear screw jacks and ball screw jacks, and each has several different options and configurations.
To determine the type of screw jack that is best for your application, you need to consider several factors, including: load, self-locking capabilities, travel rate or travel speed, efficiency, accuracy, duty cycle and price, among others.
Worm gear screw jacks
The most common jack is the worm gear screw jack, also referred to as machined screw jacks because the acme, or trapezoidal, lead screw is machined. In addition to the low cost and self-locking characteristics, another advantage of worm gear screw jacks, and all screw jacks, is the mechanical advantage achieved through the internal gear ratio resulting in the ability to lift, lower, push or pull a significant load with a relatively small amount of torque on the I/O shaft. Worm gear screw jacks are very good in multiple jack systems, because the torsional deflection of connecting shafts and couplings has little effect on positioning. Under heavy load, worm gear screw jacks are not designed for high use or heavy duty cycle applications. They also suffer from low travel rates or speed and low efficiency. However, the lack of efficiency inherent in worm gearing produces the self-locking benefit associated with worm gear screw jacks.
Ball screw jacks
Ball screw jacks incorporate a ball screw instead of a machined screw and a ball nut, which activates the screw. The advantage of ball screw jacks and the rolling action of their design is greater efficiency, up to 50%, which is much greater than bevel gear jacks and worm gear jacks. Because of their efficiency ball screw jacks can be used in heavier duty cycle applications. They also provide good positional accuracy in high speed applications. One potential disadvantage is that ball screw jacks are not self-locking and will require a brake or motor with enough holding torque to prevent the I/O shaft from back-driving. Another unique feature of ball screw jacks is their ability to incorporate worm gearing or bevel gearing. Bevel gear ball screw jacks have efficiency ratings of about 50%. This option of gearing provides another level of flexibility for all kinds of automated lifting, lowering, pushing or pulling applications that require heavier duties cycles and/or positional accuracy at high speeds. Ball screw jacks are typically at the top of the screw jack pricing spectrum, and they can be a little tricky to maintain. Despite these issues, ball screw jacks might be the best choice for your project.
Bevel gear screw jacks
Bevel gear jacks use the same trapezoidal or acme screws used in machined screw jacks to move the load. In keeping with their name, however, bevel gear jacks use bevel gears inside the housing instead of worm gearing. Bevel gears are more efficient than worm gearing—around 35% compared to 20%—and they have lower ratios that result in higher speeds and travel rates. Typically, bevel gear jacks maintain self-locking characteristics while providing higher travel speeds.
Another benefit of bevel gear jacks is their I/O shaft flexibility. They are available in single shaft, two shaft and three shaft configurations. In two and three shaft configurations the jack offers right angle characteristics with the ability to divide input power or torque, sending it equally in different directions. Flexibility in shaft configuration makes bevel gear jacks ideal for multiple jack configurations and can eliminate the need for stand-alone right angle gearboxes used in many worm gear jack systems.
Bevel gear jacks are well suited for light and moderate duty cycle applications and they are priced slightly above worm gear or machined screw jacks because of their greater efficiency, flexibility and speed characteristics. While a bit more expensive, bevel gear jacks reduce the number of required components in multiple jack systems, which helps balance the difference in price.
