The Evaluation of a General Purpose Bale System Performance and Its Bale Quality Dongil Chang 1 *, Sun-ok Chung 1 , Byoung-kwan Cho 1 , Dongseok Park 1 , Namseok Sung 1 , Jungchul Kim 1 , Inhyun Lee 2 , Jutaek Park 2 1 Department of Biosystems Machinery Engineering, Chungnam National University, Daejeon, Korea 2 Research Center, Myungsung Co., Ltd., Doil-dong, Pyeongtaek-si, Gyeonggi-do, Korea Received: August 8 th , 2013; Revised: November 11 th , 2013; Accepted: November 26 th , 2013 Purpose: The objectives of this study were to develop a general purpose baler system that is appropriate for the domestic forage cultivation environment and operated by the medium size tractor for production of bale silage made of green forage crops, and to test its performance. Methods: In a first experiment, the time of formation per one bale and densities of bales that are produced from bale system, were measured. In a second experiment, power requirement was measured by a power measurement system manufactured during bale system work. Results: The power measurement system was constructed with strain-gage sensors to measure torque of a PTO axle and proximity sensor to measure rotating speed of a PTO axle. Thus, the power requirement was calculated by PTO torque and PTO rotating speed. For evaluation of bale quality, the samples of bales were analyzed for contents of moisture, ADF, NDF and TDN. Conclusions: If the results of this study will be utilized, the coefficient of utilization of agricultural machinery will be increased by the operation of a medium size tractor that is a major disseminated tractor in farm, and it will contribute tremendously to make a forage production base for livestock farms. Keywords: Bale quality, Bale system, Performance, Power requirement, PTO Original Article Journal of Biosystems Engineering J. of Biosystems Eng. 38(4):223-227. (2013. 12) http://dx.doi.org/10.5307/JBE.2013.38.4.223 eISSN : 2234-1862 pISSN : 1738-1266 *Corresponding author: Dongil Chang Tel: +82-42-821-6718; Fax: +82-42-823-6246 E-mail: dichang@cnu.ac.kr Copyright ⓒ 2013 by The Korean Society for Agricultural Machinery This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Introduction In Korean livestock industry, the cost of feed comprises more than half of management costs. Therefore, the necessity of supplying energy source that is essential to grass-eating animal has been increasing. But it can be achieved by cultivation and utilization of winter forage crops such as green barley, Italian ryegrass, rye, using paddy fields or idle farm land, and it is a way to escape from the excessive concentrated fodder feeding. Song et al. (2009) investigated the effects of cutting heights of forage crops on productivity and quality of forage. In their study, they harvested green barley, rye, triticale, and forage wheat with baler cutting height of 5 cm, 10 cm, and 20 cm. And they analyzed and reported the production quantity, quality and economics of forage crops according to the baler cutting heights. Kim et al. (2011) analyzed power requirement of an agricultural tractor for baler operation. They developed a power measurement system and installed in a 75 kW agricultural tractor, and concluded that the power requirement of tractor was affected by the PTO rotational speed for baler operation. An energy saving model was selected by Freeland and Bledsoe (1988) for the fixed-geometry chamber type and variable-geometry chamber type baler. According to their work, energy required to form large round hay bales was affected by the operational procedure and baler chamber type. Rummer et al. (2011) evaluated two round baling systems (bio-baler and general baler) for harvesting understory biomass and reported productivity and quality of baler, and fuel consumption rate for baling systems.