Increasing the efficiency of the high-stem bast crops harvesting process

Bast crops (technical hemp, kenaf) are characterized by a significant height of crops (about 2-3 meters) and a fibrous stem structure. They are cultivated for seeds, fiber and for two-way use. The paper analyzes existing harvesting technologies, identifies the main disadvantages – an uncut stem with a height of 0.8 to 1.6 meters after harvesting seeds by grain combines, significant harvesting periods passing from the autumn of one year to the spring of the next and losses (up to 50 %) of the harvest of stems as valuable raw materials for the production of hemp fiber. According to the results of the research, an innovative method of harvesting bast crops has been proposed, which allows to harvest the entire crop and obtain primary purified seeds, as well as a trust from segments of stems of the required length for further processing. A scheme of a multifunctional device for its implementation has been developed. The expected effect of the implementation of new technical solutions is the flowability of the process, an increase in harvesting productivity by up to 30 % and the quality of trusts up to 1 variety number, a reduction in the cost of seed and fiber production by up to 20 %.