As per the boom up& down, valid stretching stroke and boom end load, there are light type, and heavy type and manned type. As per the structure, there are fixed type, moving type, fixed& rotation type, movable& rotation type.
Column and boom adopt high quality steel structure with good rigidity. The guide rail is manufactured by45 steel. After aging treatment, planting, grinding welding to keep the guide rail from deformation, to improve the precision and prolong the service life.