scissor jack bolt

screw jack bolt

screw jack bolt

A screw jack bolt, also known as a worm drive screw jack or a lifting screw, is a type of mechanical actuator that is widely used in various industries to lift, lower, push, pull, or position loads. This article provides a comprehensive guide to screw jacks, including their applications, working principle, differences from hydraulic jacks, and how to choose or customize the right screw jack for your needs.

What is a screw jack used for?

  • 1. Lifting heavy loads: Screw jacks are often used to lift and support heavy loads in manufacturing, construction, transportation, and other industries. They can lift loads ranging from a few pounds to thousands of tons, depending on their size and configuration.
  • 2. Leveling surfaces: Screw jacks can also be used to level or adjust uneven surfaces, such as floors, platforms, or machinery. By adjusting the height of the screw jack, you can compensate for the irregularities of the surface.
  • 3. Positioning equipment: Screw jacks are also used to position equipment or machinery precisely. For example, in the automotive industry, screw jacks are used to adjust the position of car parts during manufacturing.
  • 4. Stabilizing structures: Screw jacks can be used to stabilize structures, such as buildings or bridges, by supporting them or by providing resistance against lateral forces.
  • 5. Moving heavy objects: Screw jacks can be used to move heavy objects horizontally or vertically, such as sliding doors, gates, or cranes.

screw jack

What is the working principle of screw jack?

The working principle of a screw jack is based on the mechanical advantage of a screw thread. When a force is applied to the handle or motor of the screw jack, the screw thread rotates and moves the lifting nut, which in turn moves the load. The pitch of the screw thread determines the amount of linear motion produced by each rotation of the screw. The load capacity of the screw jack depends on the size and material of the screw, the number of threads, and the efficiency of the nut and bearings.

screw jack

What is the difference between a screw jack and a hydraulic jack?

Although both screw jacks and hydraulic jacks are used for lifting and positioning loads, they have some differences in terms of their working principle, advantages, and disadvantages.

  • 1. Working principle: Screw jacks use screw threads to move the load, while hydraulic jacks use pressurized fluid to create force and motion.
  • 2. Advantages of screw jacks: Screw jacks are more compact, reliable, and cost-effective for low to medium loads and travel distances. They do not require external power sources or complex control systems.
  • 3. Disadvantages of screw jacks: Screw jacks are slower, less precise, and have lower efficiency compared to hydraulic jacks. They may also have limitations in terms of temperature, speed, and load capacity.
  • 4. Advantages of hydraulic jacks: Hydraulic jacks are faster, more powerful, and more precise for high loads and long travel distances. They can also operate at higher temperatures and pressures.
  • 5. Disadvantages of hydraulic jacks: Hydraulic jacks are more complex, expensive, and require more maintenance and safety precautions. They may also have issues with leaks, noise, and environmental impact.

How to choose or customize the right screw jack?

The selection and customization of a screw jack depend on various factors, such as the type and weight of the load, the required travel distance, the speed and accuracy of positioning, the environmental conditions, and the available space and power sources. Here are some important parameters to consider:

  • 1. Load capacity: The load capacity of a screw jack should be equal to or greater than the weight of the load, plus any dynamic or static forces that may act on it.
  • 2. Travel distance: The travel distance of a screw jack should be sufficient to cover the required range of motion, taking into account any safety margins and end stops.
  • 3. Screw pitch: The screw pitch of a screw jack determines the linear motion produced by each rotation of the screw. A finer pitch provides higher precision but lower speed, while a coarser pitch provides higher speed but lower precision.
  • 4. Screw diameter and lead: The screw diameter and lead of a screw jack determine the mechanical advantage and load capacity of the screw. A larger diameter and lead provide higher load capacity but require more torque to operate.
  • 5. Nut type and material: The nut type and material of a screw jack affect its efficiency, wear resistance, lubrication, and noise level. Bronze, plastic, or PTFE nuts are common choices.

screw jack

About HZPT

As a leading manufacturer of industrial motors, gearboxes, and drives in China, HZPT is committed to delivering innovative solutions and superior quality products to its customers worldwide. Our main products include micro gear motors, medium gear motors, brake motors, torque motors, DC motors, NMRV worm gearboxes, bevel gearboxes, WPRV worm gearboxes, rigid face gear reducers, spiral bevel gear reducers, helical gear reducers, parallel shaft gear reducers, screw lifts, and planetary gear reducers, which are widely used in various industrial production lines, such as transportation machinery, food machinery, medical machinery, printing machinery, textile machinery, packaging machinery, office equipment, and instruments. Our products are the preferred choice for automation equipment.

Why choose HZPT screw jacks?

  • 1. High load capacity: Our screw jacks can lift loads ranging from 0.5 tons to 150 tons, with a maximum stroke of 6 meters. They are made of high-quality steel, with precise machining and heat treatment, to ensure high load capacity and durability.
  • 2. High precision: Our screw jacks have high accuracy and repeatability, with a positioning accuracy of up to 0.01 mm and a speed of up to 1500 mm/min. They are suitable for applications that require precise positioning and synchronization.
  • 3. Customizable design: Our screw jacks can be customized to meet your specific requirements, such as different stroke lengths, screw pitches, screw diameters, nuts types, and motor sizes. We can also provide accessories and mounting brackets to facilitate installation and operation.
  • 4. Easy maintenance: Our screw jacks are designed for easy maintenance and lubrication, with low noise and vibration. They require minimal maintenance and can last for years without major repairs.
  • 5. Competitive price: Our screw jacks are priced competitively, without compromising on quality or performance. We offer flexible payment and delivery options to meet your budget and schedule.


Find us

Ep Screw Jack Co., Ltd.

Mail: [email protected]

As one of leading manufacturers, suppliers and exporters of mechanical products in China, We offer reducers, sprockets, industrial and conveyor chain, belts, pulleys, gears, racks, gearboxes, motors, PTO Shafts, taper lock Bushing, vacuum Pumps, screw air compressors and many other products. Please contact us for details.