Research On Structure Design And Forming Technology Of Split Wheel Mounted Brake Disc

With the rapid development of rail transit construction,in order to effectively reduce the operating cost of the enterprise,it is of great significance to design the split wheel mounted brake disc structure with independent intellectual property rights in China,and to reasonably design its casting forming process to ensure the casting quality and save the production cost.Based on the six point positioning principle,this paper designs the positioning structure between the disc body and its connecting accessories,and uses Solid Works software to model the wheel mounted brake disc with four different connecting structures.Based on the numerical simulation technology,the thermal stress coupling simulation analysis of four kinds of structure split wheel mounted brake disc is carried out.According to the analysis results,the collaborative design of the structure and forming process of split wheel mounted brake disc is completed.The main research contents and conclusions are as follows:(1)On the premise that the elements such as radiator rib and split connection structure can meet the requirements of heat dissipation characteristics and six point positioning principle,the structural design of split type wheel mounted brake disc is completed.The advantages and disadvantages of four types of split type wheel mounted brake disc are summarized from the aspects of installation convenience,reliability,casting technology and machining technology.(2)Using the sequential coupling calculation method,under the three emergency braking conditions with initial speed of 120 km/h and the normal braking conditions,the maximum temperature of the four structures reaches 275.55 ℃ and 229.3 ℃,the maximum temperature appears on the friction surface of the brake disc,the minimum temperature appears at the end of the radiator,and the maximum temperature of the friction surface is 350 ℃ lower than the specified allowable temperature.The maximum first principal stress of bolted,mortise,plug-in and lap type is 231 MPa,142 MPa,730 MPa and 305 MPa respectively under the three emergency braking conditions,and 105 MPa,97 MPa,650 MPa and 221 MPa respectively under the normal braking conditions.Except for the mortise type split wheel mounted brake disc,the other three structure split discs all meet the safety allowable stress standard under the corresponding temperature.(3)Using Pro CAST casting simulation software to simulate the pouring of brake disc,through the mesh division,pre-treatment,post-treatment and other links,taking into account the characteristics of filling,temperature field and shrinkage cavity distribution,analyzing the location and causes of defects,which in turn provides a theoretical basis for the optimization of process plan.The self feeding ability of the casting is enhanced by adding a necking open riser on the top of the casting.Finally,Pro CAST software was used to simulate the optimized process,and the casting process of split type wheel mounted brake disc was obtained.The research results obtained in this paper provide a theoretical basis for the industrial production of split brake discs in China.