Resumo

CAMACHO, Jesús H.  e  MAGALHAES, Paulo S. G.. A study of operational parameters of double discs and parabolic chisels for applications on areas with surface crop residues. Agric. Téc. [online]. 2004, vol.64, n.1, pp. 58-65. ISSN 0365-2807.  doi: 10.4067/S0365-28072004000100007.

One of the main restrictive aspects of no-tillage is the handling of crop residues during amendment and fertilizer application, since when it is not carried out simultaneously with sowing, it is necessary to distribute these products on the surface to maintain the soil cover. The objective of the present study was to evaluate the operational capacity of a prototype designed with double disks, chisel tine and subsoiler, which allows fertilization at a depth between 0 and 0.30 m. The experimental design was randomized blocks, with seven treatments and four replicates. Behavior of the horizontal and vertical forces, soil area disturbed, work depth and specific resistance were analyzed. The results indicated that the use of double disks in front of the chisels reduces the horizontal force and the disturbed area, but these results do not differ statistically. The treatments with chisels had higher values of horizontal force, higher disturbed areas and similar specific resistance. The combination of double disks and chisels reduced the vertical force. The maximum working depth was observed for the treatments with double disks and subsoiler. The double disks had smallest horizontal force, shallowest working depth, smallest disturbed area and the highest specific resistance.

Palavras-chave : agricultural tools; agricultural machinery; soil tillage.