This research practically discusses and presents the stages of design process in product development. Design process was realized through CATIA. The product developed is an agricultural device called as “disc harrow”. Therefore, agricultural details are presented together with machine design. A roller system is added to disc harrow in this study. Thus; the current system and the additional roller system are discussed with the principles of methodological construction and design objectives are defined. Both the current system and the additional roller system are designed in parallel with these objectives. Structural stress analysis is performed at different kinetic positions of the disc harrow connection of the roller system. System design is achieved by considering the feedback from such analyses and design objectives. The hereby design is obtained. The additional roller system is mounted and field survey is carried out. Contribution of the roller to disc harrow process, defined design objectives, ratio of the realization of design objectives and results of stress analyses are evaluated.