Self-propelled combines for the harvesting of grain maize are made up of two main sub-ensembles: maize cob cropper and maize stem thrasher. The maize cob cropper detaches the maize cobs from the stems, carries the leafless maize cobs to the thrasher and chops the stems. Chopped stems can be recovered in a mean of transportation (tow) or they can be spread over the soil to be later incorporated into the soil. The thrasher thrashes the maize cobs, separates the grains from impurities, and carries the grains to the bunker. Scientific organisation of harvesting grain maize can result in shortening the harvesting period and in increasing labour productivity. To reach all these objectives and to rationally exploit the combines, we need to take such organisational measures as preparing the crop for harvesting, choosing the way combines move in the field, ensuring transportation means, etc. Preparing the field for harvesting starts with identifying ripening state, continues with marking the places with risk for the combines and establishing the access routes for the transportation means, and it ends with identifying fire guard spots. Self-propelled combines enter the plot without opening roads previously because the working width is larger than the thrasher width (it is a T working flow). First, we harvest the ends of the plot (that were sowed transversally), to ensure turning areas for the combines and to allow the access of the means of transportation and of other means necessary for harvesting. Harvesting maize grains with self-propelled combines is done with low losses (grain moisture below 20%). Analysing exploitation and economic indices, we can draw the following conclusions: the self-propelled combine CASE-IH 7088 + CS-8 harvests maize from eight rows over a width of 5.6 m. The combine is equipped with a Diesel engine of 325 HP and it has an hourly productivity of 24 t/h with a feeding flow of the thrashing device of 18 kg/s. For a production of 6 t/ha, fuel consumption reaches 11.2 l/ha (1.0 l/t) and total expenses upon harvesting grain maize reach 79.5 RON/ha, i.e. 13.3 RON/t. To obtain high yields per area unit with low expenses, we need to strictly observe cultivation technologies and use as complex as possible aggregates with the highest efficiency possible.

combines, CASE-IH 7088 + CS-8, exploitation

sciences soil

Presentation: poster