Abstract: A double-surface contact tray loading base comprises a loading surface (4) and a hook (1) arranged on an outer end of the loading surface (4), the hook (1) comprises a hook lug (1-2) and a support plate (6), the hook lug (1-2) is arranged on an upper side of the outer end of the loading surface (4), and the support plate (6) is arranged on a lower side of the outer end of the loading surface (4), thus forming the double-surface contact tray loading base.

Abstract: A sub-frame radial bogie comprises wheelsets, a side frame, a swing bolster, a wheelset radial device and a brake gear. Bearing adapters (41) forming the wheelset radial device are fixedly connected with the sub-frame (42) via pulling rivets (11), and each group of the bearing adapters (41) is bilaterally symmetrical in structure with a symmetry plane (A). The sub-frame (42) comprises an arm (51) and an end (52); a sub-frame connection hole (61) is arranged on the end (52); transverse positioning bosses (73) are arranged on the bearing adapters (41); and an arc groove (75) and symmetrical sub-frame connection holes (71) are arranged on a connection base (72). The bearing adapters use the same standard structure, hence, the more precise design and machining can be realized, and the cost is reduced, and meanwhile, the maintenance technique of the sub-frame is improved, and the maintenance cost is reduced.