![<?echo $_SERVER['SERVER_NAME'];?>](/template/twentyseventeen/skin/images/header.jpg)
Reason analysis The gear box structure before improvement is shown in the figure. The whole gear box is divided into upper and lower cases. The upper and lower cases are welded by steel plates. The partition surface is made of 17mm@30mm steel plate, and the side plate and bottom plate are made of 5mm steel plate. The connection of the box body is not only fastened by bolts at both ends, but also two long bolts on each side are connected to the upper and lower tanks through the bolt seat. There is no relative movement between the gear box and the traction motor output end and the rolling hoop shaft box. The rubber seal is sealed, and the labyrinth seal is used between the gearbox and the driven gear due to relative motion. The gearbox has three suspension points that are bolted to the traction motor and the axle housing. The gearbox weighs about 130kg.
Analysis of this gearbox structure, we believe that the following shortcomings: the connection between the side plate of the gearbox and the bottom plate is as shown, when the gearbox motor under the improved gearbox motor and the vibration from the wheelset are transmitted to the gearbox, the side plate As the main force-receiving part, the joint weld of the bolt seat of the side plate and the lower suspension point is subjected to a large dynamic load, and thus fatigue crack is easily generated here.
The gearbox end plate welding method holds the axle box suspension point. The vibration of the axle housing is transmitted to the gearbox through this point. The welding method of the connecting plate and the terminal surface of the sub-tank is as shown here. The seam is small, but it is very stressed, so it is also prone to fatigue cracks. The connecting bolts on the upper and lower bins are welded to the side plates. When the bolts are tightened, the side plates are subjected to a large force. Due to the presence of a bending moment, the side plates are concave, so that the bolt seats will be alternating when the locomotive is running. The load acts to make the sub-tank surface seal tight and leak, and the root of the bolt seat is also prone to fatigue cracks. The gearbox is too heavy. Under the premise of the same vibration acceleration, the heavier the gearbox, the greater the force of the three suspension points of the gearbox, the more likely it is to cause damage. Therefore, we must find ways to reduce the weight of the gearbox and improve the stress state of the gearbox. At the same time, the rigidity of the gear box should be maintained to prevent the bolt from loosening and oil leakage after deformation. After the locomotive speeds up, the speed of the gear increases in the gearbox, and the positive pressure formed in the gearbox also increases, which requires the gearbox to have better ventilation capability. The ventilator area of ​​the improved front gearbox is too small, and it is easily blocked by grease, which is not easy to reduce pressure in time, so that the grease in the gearbox leaks from the bin face.
Solution The structure of the improved gearbox is as shown. The whole gear box is divided into upper and lower cases, and the upper and lower cases are welded by steel plates. The partition surface is made of 17mm@25mm steel plate, the side plate and bottom plate of the upper case are made of 3mm steel plate, and the lower case is made of 4mm steel plate. The connection of the upper and lower cabinets is directly fastened together by bolts at both ends, and the connecting bolts on the side are also directly mounted on the sub-tank surface. The output of the gearbox and the traction motor and the rolling axle housing are sealed by rubber seals because there is no relative movement, and the labyrinth seal is still used between the gearbox and the driven gear due to relative motion. The gearbox has three suspension points that are bolted to the traction motor and the axle housing. The gearbox weighs approximately 104 kg. The main improvements are as follows.
Reducing the weight of the gearbox reduces the weight of the gearbox. It is very advantageous to change the stress state of the suspension point of the gearbox. Therefore, the side plate and the top plate of the upper casing are made of 3mm steel plate, and the binning surface is changed from the original 17mm@30mm. 17mm@25mm, 4mm steel plate is used for the side plate and bottom plate of the lower box. The weight of the gear box is reduced from 130kg to 104kg. The weight is reduced and the stiffness is reduced. To solve this problem, we take the following measures: 1 pair The side plates are pressed to strengthen the rigidity of the side plates; o the connecting plates connecting the front and rear side plates are added in the gear box, one upper box body and two lower box bodies. By taking measures, the rigidity of the gearbox is significantly increased.
Nantong Dongfang fitness equipment Co., Ltd , https://www.dongfangfitness.com