The 50 -ton spiral jack is a mechanical jack. The spiral jack is a mechanical device that is commonly used to rise to the top. When a small external force is applied, it can raise a heavy heavy object. Keep a balanced state in the original position and will not fall. The spiral jack uses the swing of the joystick to rotate the small gear. After running a pair of cone gear, it drives the screw to rotate and push the lift sleeve, which rises or decreases heavy objects. If it is a relatively soft ground, such as mud road or sandy pavement surface, it is recommended to use wooden boards or slate pads under the top of the jack before using the jack to reduce the pressure to prevent the pounds from being caught in the soft ground.