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At present, the hole formed by the pit-type transplanter has poor stability, which is easy to collapse, and the soil backflow is serious. Aiming at the transplanting characteristics of the water flushing well cellar type multifunctional transplanting machine and the agronomic requirements of well cellar transplanting technology, in order to improve the quality of the hole and reduce the rate of seedling leakage, a hole-forming drill was designed, and its main structure and work were expounded. Mechanism and perform performance tests were carried out. The burrowing process was divided into three stages. Through the research methods of dynamics and kinematics, the force of soil particles in each stage was analyzed, the key structural parameters and operation parameters were determined, and the relationship between the key operation parameters and the burrowing quality was clearly analyzed, and the burrowing was improved. Taking the number of soil particles in the grid bin group as the response index, a discrete element simulation experiment was carried out, and the value range of each factor was determined by statistical analysis of the least significant difference;a quadratic orthogonal rotation combination experiment was arranged, and the Design-Expert software was used to analyze the test data, and the order of the influence of each factor on the index value was obtained. The results showed that the drill bit diameter was 100mm, the pitch was 75mm, and the rotational speed was 350r/min. The device had the best performance. The depth of the hole and the diameter of the hole were 182mm and 80.7mm, respectively. The optimization factors were tested and verified, and the test and optimization results were basically consistent, meeting the agronomic requirements of well cellar transplanting.