Research on the tangential threshing device is extensive, yet further exploration into the design and adjustment of multi-drum systems remains crucial. Key issues affecting efficiency and harvesting quality persist, particularly concerning grain breakage, which impacts germination, suitability, storage, and ultimately, selling price. The design and adjustment of these systems create a conflict between effective separation, threshing, and minimizing broken grain. This has led to increased interest in extending adjustment parameters, particularly concerning concave clearance. Experimental investigations have been conducted using a new test rig that allows variable adjustment of both pre and main concaves, achieving an individualized concave clearance. While the circumferential velocity of the threshing drum and throughput are dominant factors, concave adjustment significantly influences threshing losses and grain breakage. Increased velocity or reduced clearance correlates with higher breakage rates, highlighting the relationship between impact height, frequency, and breakage. This necessitates further investigation into grain breakage to develop a comprehensive analysis method, forming the basis for a breakage model that simulates realistic rebound at high impact velocities. This model must encompass the mechanical and strength properties of grain, requiring an understanding of both static and dynamic strength behavior. A new t
