When the ploughing hand tractor pulls a one-way double-share plow operation, one side drive wheel is on the uncultivated land and the other side drive wheel is in the furrow. The adhesion coefficients between the two wheels and the ground are different, and the slip rates are different, causing the unit to often deviate in one direction. For Dongfeng-12 hand tractors, the following adjustments can be made to solve the problem: adjust the gap value (swing gap) between the left and right adjustment screws on the traction frame and the intermediate connecting frame, adjust the 681 unidirectional double-share plow to about 1.5mm, and adjust the 1LS-220 and 701 unidirectional double-share plow to about 5mm. During the plowing process, if you find that the tractor is still tilting to the right, you can loosen the two fastening screws, shorten the protruding part of the left adjustment screw, and long the protruding part of the right screw. Until the armrest unit is released, it can drive normally along the groove wall. Possible reasons for deflection in rotary tillage operation: the tail wheel is deformed again, the tail wheel shaft is not assembled in the fork, etc., causing the tail wheel to deflect: the bearings on the tail wheel shaft are damaged or severely worn: the coulter is installed incorrectly or broken or dropped. When a rotary tillage operation occurs, the relevant parts should be corrected, repaired, reinstalled or replaced according to the specific circumstances. Before solving the problem, try not to use the steering clutch to correct the deviation, but use the method of pushing and pulling the armrest. When sowing operation, hand tractors perform sowing operations. There are two supporting situations: one is a trailed seeder. Such as ABQ-8 grain seeder; the second is ZBG-6A rice and wheat strip seeder with synchronous transmission. The main reasons for the unit deviation in sowing operations are that the installation height of the seed head (or trench opener) in the sowing pattern direction is inconsistent or the left and right asymmetry, errors or breakages and falls during configuration and installation of the rotary cutting coulter, and deformation of the traction frame, etc. Due to the above reasons. During sowing operations, the resistance is subjected to varying degrees in the sowing direction, resulting in torsional torque, causing the unit to deviate. To this end, the technical status of the seed machine should be carefully checked before sowing operations, and the rotary cutting coulter should be configured and installed according to regulations. The seed head (or groove opener) should be symmetrically arranged. Ensure that the installation is highly consistent and meets agronomic requirements. The hand tractor in the harvesting operation is mainly equipped with 4GL-130 type harvester. The main reason for the unit deviation is that the cutting edge direction of the harvester is adjusted in a different way. Differences in cutting resistance: one cutting knife is high and the other is low, the cutting heights are different during harvesting, and the operation resistance is not equal; the cutting width is not appropriate; the ground is uneven. Corresponding measures should be taken for specific reasons. Generally, hand tractors are equipped with 1KSQ-35A (front-mounted) or 1KSH-35A (rear-mounted) small disc trenchers, which are mainly used to excavate field drainage ditches. The main reasons for the poor linearity of the trench operation: the deviation of the center line of the cutter plate and the center plane of the hand tractor drive wheel shaft exceeds the specified (1KSQ-35A allowable deviation 8mm, 1KSH-35A allowable deviation 5mm): the cutter plate is twisted and deformed, and the frame is deformed and skewed. The coulter is installed incorrectly, the coulter breaks, falls off, etc. Pay attention to inspection and correction of the cutter plate and rack. Install the rotary cutting coulter correctly and carefully adjust the position of the cutter plate. If the coulter is found to be broken or fall off, the machine should be stopped immediately. Replace parts. Irrigation and threshing operations equipment