A screw jack is a mechanical transmission device used to convert rotary motion into linear motion, which is suitable for a wide range of industrial applications. They include a worm gearbox mechanism in which the alloy steel worm rotates a high-strength bronze worm gear. The rotation of the worm gear causes linear movement of the lifting screw or the moving nut on the screw. The screw jack can realize the linear motion solution of precise positioning and smooth operation. They can be used for load capacities from 5kN to 2000kN. The linear motion speed and bearing capacity of the lifting screw depend on the worm gear’s thread size, pitch, and rotation ratio.