| With the accelerating development of global technology and the speeding pace of peoples,life,high-speed transportation is the major project which is the important development of countries.Environment pollution and road congestion caused by cars making cities cannot be bear the heavy load,the best way to solve this problem is developing high-speed rail transportations,and countries are focusing on construction of high-speed railway nowadays.The technology of high-speed railway plate,type of CRTS III,is the independent intellectual property of China which is the international leading and the sign of “Made in China” step out to the world.However,the domestic existing construction technology of CRTS III plate is pedestal pre-tensioning process,this technology is backward because of low output,high energy and labor cost,heavy environmental pollution,and what's more,it's requires large-scale factory with high investments of plants,foundation pits,basic and production equipments which cannot be used once more and causes huge wastes.The most important shortcoming of this process is that it cannot realize tensioning and losing to the prestressed steel rods at the same time,what causes uneven stress of the plates and making finished plates warping deformation.Aiming at overcome the disadvantage of traditional manufacturing process,an intelligent manufacture pipeline technology for CRTS? railway plate is proposed.Using pre-tensioning process,tension of steel rods is undertaken by mould itself instead of by base beams.Manufacturing quality and efficacy is improved by changing manufacturing process from fixed pit method to production pipeline mode.The most key technology of proposed production process is the two procedures of tensioning and losing for the prestressed steel rods at the same time,and this paper is aiming at to solve those two critical problems.By the means of technology analysis of tensioning and losing process,and for the synchronism requirement of tensioning and losing process with 80 steel rods,this paper has studied an automotive device which is not only reliable and durable in construction site but also can easily realize collection and transmission for big data of tensioning and losing process,and then provides technical fundament to realize the intelligence of the whole production line.This thesis has compared different synchronization mechanism schemes,the segmental gear-rack meshing device transmission plan has been selected,which effectively deals the problem of synchronization tensioning and losing with multiple gear-rack device theoretically.The technical difficulty of this plan is how to location and alignment,how to ensure the assemble and meshing accuracy of gear-rack devices and how to ensure the 80 rods surrounded by tensioning-losing beams could tensioning and lose at the same time.Hydraulic systems and pneumatic systems of synchronous tensioning-losing work positions have been also designed in this project.What's more,the key elements of hydraulic and pneumatic systems under working condition have been analyzed,its working schematic diagram has been also optimal designed.The meshing difficulty of gear and rack has solved by using segmental sliding rack,by method of corner rounding for addendum and sides of gears,etc.Optimization for design based on the structure design has been performed by advanced means such as strength calculation and finite element analysis.Software Creo2.0 has applied to 3D modeling,software ANSYS has been used to analysis for deformation of tensioning-losing bracket,providing theoretical data for compensation of rack position on tensioning-losing beams,position accuracy problem of gear and rack has been solved.Practical equipments of this project had been tested and debugged in working scene to demonstrate the working performance of proposed tensioning-losing device.The working performance shows that the device has reached design objective,the indicators have also met the design requirements. |
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