In the extermination operation, a large number of rotary cultivators or rake machines are required. Rotary tiller gimbal damage often occurs during operations. Analysis of failure phenomena is nothing more than the following reasons. 1. Most operators do not know that the universal joint of the rotary cultivator has been subjected to dynamic balance experiment and calibration before leaving the factory. Therefore, when installing, it must be noted that the fork joints at both ends of the intermediate shaft must be on the same plane. Some types of universal joints have lock blocks inside the square sleeve, and there is a groove on the square shaft. Be sure to install them in the direction when installing. 2, the universal joint model is different, the size of the structure slightly different, to choose the right model. For example, the same genus of Lianyungang are all rotary cultivators with cultivating width of 1.8 meters. The appearance of the universal joints is basically the same, but the Shanghai-50 matching rotary cultivators and the Jiangsu-504 supporting rotary cultivators have slightly longer shafts and shaft lengths. Differently, the former sleeve and shaft are slightly shorter than the latter. It can be mounted on each other during installation and use, but it is easily overlooked by the operator. The square shaft and the square sleeve are sliding joints. When the rotary cultivator moves up and down or swings left and right, it can freely expand and contract. It will neither fall off nor fall into the fork of the top dead sleeve. If the Shanghai 50 tractor is equipped with a rotary cultivator, the wrong installation A slightly longer square shaft or bushing will cause the axle shaft of the power output shaft of the tractor to break or support the top of the bearing. In severe cases, the top of the rear axle housing can be scrapped. So be sure to find out if the model is installed before you can work. 3. When the cultivator is working down to the ploughing depth, it is necessary to check if the first axis of the universal joint and the rotary cultivator is close to the level, otherwise, adjust the center pull rod on the suspension to ensure that the rotary cultivator is in the best technical condition. If you want to work, if the head of the locomotive operation needs to be lifted, turn it up as low as possible to prevent the gimbal angle from being too large, and spoil the gimbal assembly. According to the practice and access to relevant information, when the universal joint angle exceeds 35 degrees, the noise will gradually increase, and when it exceeds 45 degrees, it will be credited to death.