Screw Jack Introduction

/Screw Jack Introduction

What is Screw Jack?

screw jack image

Screw Jack (also known as Worm Screw Jack, Machine Screw Jack or Lead Screw Jack). It is a gearbox assembly (either worm gear or bevel gear) and a transmission product (machine cut lead screw or a rolled or ground ball screw) which through use of a motor is used to convert rotary into linear motion. Wherever there is a need to lift, position, align and hold the load, there is screw jack.

We mainly offer below types:

  • The gearbox assembly either in worm gear(SJC seriesSJW seriesSJB series) or in bevel gear(SJH series).
  •  Anti-Backlash Actuators, Machine screw jack, Ball Screw jack, Bevel Gear Jacks, Stainless Steel Screw Jacks, Metric Screw Jacks, Anode Jack, Screw Jack System & Necessaries.

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. SIJIE screw jacks and lifting systems offer wide-ranging lifting and positioning solutions for diverse industries.

screw jack application
  • Gypsum factories
  • Sheet metal forming machinery
  • Paper, press, printing industry
  • Food processing machinery
  • Construction sectorMechanical lifting applications
  • Bridge jacks for road and bridge lifting
  • Platform lifting applications
  • Opening and closing of penstocks
  • Industrial process
  • Roll form machinery
  • Stage setup applicationsShipyards
  • Mining industry
  • Lift tables
  • Defense industry

Mechanical Advantage of Screw Jack

SIJIE 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.

Different types of screw jack

There are a few screw jack design available including Translating, Keyed and Traveling Nut. All of them can be achieved with either a machine screw jack or ball screw jack. Want to know which jack design is best for your application? Below details may help you.

Translating screw Jacks

worm gear Translating screw Jacks

Worm gear Translating screw Jacks

bevel gear Translating screw Jacks

Bevel gear Translating screw Jacks

Translating screw Jacks are most often selected. The main components of screw jacks are gear housing, trapezoidal lifting screw, worm screw and worm gear. Worm screw is rotated manually or by motor, then the worm gear will be rotated by the worm screw and the lifting screw moves through the rotating worm gear. The linear motion speed of lifting screw depends on thread size and rotation ratio of worm gears.

Traveling Nut screw Jacks

Traveling Nut worm gear screw Jacks

Traveling Nut worm gear screw Jacks

Traveling Nut bevel gear screw Jacks

Traveling Nut bevel gear screw Jacks

Traveling Nut screw Jacks are another option.  The lifting screw does not move up and down. It only rotates around its axis.  The travelling nut moves along the screw. The lifting nut of screw jack is made of bronze to decrease friction. This type of jack is ideal for applications that cannot accommodate a screw protection tube or that require a flush mount.

Keyed screw Jacks(anti-rotation)

keyed screw jack

Keyed screw Jacks(anti-rotation screw jack) are used any time rotation of the lifting screw is not restrained. For instance, when you must lift the jack to meet a load. This is how they work: A key, fixed to the jack housing and inserted into a keyway milled into the length of the lifting screw forces the lifting screw to translate without rotating. It is available in translating models.