An agricultural device (1) for processing crop comprises a trailer (2) with an undercarriage (3) and a crop-processing device (8) which comprises a tilting frame (9) tiltable about a transverse tilting axis (19). Two supporting arms (20, 21) are connected to the tilting frame so as to be pivotable about a swivel axis (22, 23) transverse to the tilting axis. The supporting arms comprise a plurality of supporting arm portions (24, 24A) hingable about hinge axes (25) parallel to the swivel axis and having rotatable crop-processing members (26). The device has a transport position, with the tilting frame in a raised, the swivel axes in a vertical, and each supporting arm in a collapsed position. During the move to the operating position, each supporting arm is swung to extend outwards. Subsequently, the tilting frame is tilted downwards. An actuating member (31) between two adjacent supporting arm portions keeps said supporting arm portions in line with each other while being swung outwards, such that the centre of gravity (Z) of the crop-processing device is situated behind the tilting axis and the crop-processing device lowers by its own weight.
