The utility model relates to a steam generator tubes nondestructive test and maintenance technical field specifically disclose a full pneumatic type tube sheet crawl device structure. Movable part and base part are intercrossing's structure in this crawl device to at the movable part both ends of homonymy and the base part both ends fixed toe that is equipped with respectively, the movable part is connected with the base part through sharp driver part, rectilinear movement on the axis of movable part of messenger's base part whole edge, the base part is connected with the movable part through swinging member, makes the base part swing for the movable part or rotatory certain angle, toe on movable part and the base parts is scalable and tight or unclamp with the heat transfer pipe clamp of tube sheet heat -transfer pipe. This result has improved the stability and the security of equipment, has got rid of the uncertain risk that motor drive and hydraulic drive brought, has greatly reduced inspection personnel's intensity of labour, simultaneously, accessible logical order and path planning realize the location on the tube sheet heat -transfer pipe.