The working principle of screw jack mainly uses the screw self-locking principle and lever principle to transmit force. In essence, it is a kind of screw transmission of force.

When in use, first adjust the supporting teeth, adjust the teeth and adjust the ratchet wheel clockwise, then the internal gear rotates, and the lifting sleeve rises until the top plate contacts with the heavy objects. Then use the handle to pull the rotating ratchet group up and down to drive the internal gear to rotate, so as to rotate the screw and push the lifting sleeve to realize the jacking of heavy objects.

When a red warning line appears on the lifting sleeve, it indicates that the rated height has been reached and the jacking shall be stopped immediately. At the end of the jacking process, when descending, pull out the handle, reset the supporting teeth, and turn the ratchet group counterclockwise to lower the weight. After the horizontal screw is installed at the bottom, the weight can be moved laterally for a small distance. Pay attention to maintenance and repair after use, conduct lubrication treatment regularly, take anti rust measures during cleaning, and use diesel oil for cleaning and wiping.