Kinematics, workspace, dynamics behavior of a 3-DOF 3-Legged parallel robot with horizontal slide 3-link for steel snagging, which was developed by Northeastern University, are introduced. The steel spot snagging experiments have also been carried out. The wheel selection, removal rate, grinding power and their influence factors are studied. Comparing with hanging grinders used in most steel mills of our country, this robotic grinder can reduce labor intensity of workers, raise efficiency and guarantee quality greatly.