According to structural features, the jack can be divided into rack jack, screw jack and Hydraulic Jack.
1. Rack jack is driven by the human through the lever and gear to lift weight. The general weight is not more than 20 tons, supports long-term lifting heavy objects, mainly used in operating conditions inconvenient or need to use the lower claws to lift heavy objects occasions, such as rails from the track operations.
2. Screw jack works by the human through the screw drive, using screw or nut sleeve as the top pieces.
3. Hydraulic jack works by the human or electric to drive hydraulic pump, through the hydraulic system driving, with the cylinder or piston as the top pieces. Hydraulic jacks can be divided into integral and separate products. In another ways, it includes Hydraulic Bottle Jack and Hydraulic Floor Jack and so on.