Abstract: A movable side wall and opening/closing mechanism for railroad boxcars, comprising a side wall assembly (1), an end-portion opening/closing mechanism (2), a hinged rod assembly (3), a lateral door central clamping device (4), a upper transmission shaft assembly (5), a lower transmission shaft assembly (6), a upper track assembly (7) and a lower track assembly (8); upon loading/unloading cargo, the movable side wall can be opened further, so as to allow multiple forklifts of any tonnage on the ground to load/unload cargo to/from any positions of a carriage; the hinged rod assembly (3) and the central clamping device (4) are provided to keep the movable side wall reliably closed in order to ensure security and self-locking during transportation.

Abstract: The present invention discloses a connecting rod type two-level locking device, a hopper car bottom door and a hopper car, and belongs to the technical field of rail wagons. The connecting rod type two-level locking device includes a transmission shaft, a door opening arm, a first roller, a second roller, a first locating pin, a standstill locking disk and a linkage mechanism. The hopper car bottom door includes the connecting rod type two-level locking device. The hopper car includes the bottom door. Even if the connecting rod type two-level locking device is accidentally stressed, the linkage mechanism cannot rotate, and at this time, the slave arm cannot rotate neither. The accidental opening of the hopper car bottom door can be avoided. The hopper car is more reliable to use.

Abstract: The invention provides an engineering vehicle having a ballast unloading device (100) and a ballast leveling device (200). The engineering vehicle includes a vehicle body (10), and the ballast unloading device (100) and the ballast leveling device (200) arranged on the vehicle body (10). The ballast unloading device (100) includes: a ballast carrying portion (20) provided with ballast unloading openings (21), and the ballast carrying portion (20) being arranged on the vehicle body (10); ballast unloading doors (30) capable of rotating relative to the ballast carrying portion (20), inner unloading passages (31) and outer unloading passages (32) being arranged on the ballast unloading doors (30), the ballast unloading doors (30) further including stop portions (33) located between the inner unloading passages (31) and the outer unloading passages (32).

Abstract: A side wall structure of an open wagon includes an upper side beam (1), wherein built-in pillow columns (3) and built-in side columns (4) are arranged on the inner side of the upper side beam (1), the upper side beam (1) is formed by pressing an outer side flanged plate (1a), an upper planar plate (1b), an inner side slope plate (1c) and a lower vertical plate (1d), the upper parts of the built-in pillow columns (3) and the built-in side columns (4) are welded on the inner side slope plate (1c) and the lower vertical plate (1d), built-in small upright columns (5) are respectively arranged on the outer sides of the built-in pillow columns (3), between the built-in pillow columns (3) and the built-in side columns (4) that are adjacent and between every two adjacent built-in side columns (4), and the upper parts of the built-in small upright column (5) are welded on the inner side slope plate (1c) and the lower vertical plate (1d); each side wall plate (2) includes a straight side wall plate (2a) and arc-shaped