Study On The Process Balance And Cycle Time Optimization Method Of Automotive Engine Cylinder Head Machining Production Line

Automotive powertrain machining with high flexibility and efficiency characteristics,is the field of intelligent manufacturing major breakthroughs.As automobile demand becomes more diverse,digital manufacturing has become the current trend of manufacturing transformation and development.The machining production of automotive powertrain components,such as engine cylinder heads,requires low cycle time and high machining balance rates.At present,in most production lines,machining processes are designed manually.Changing the product or product model requires re-planning,which leads to low process design efficiency.And for the flexible production line,it is difficult to find the best process for the parts due to the constraints of human experience.Aiming at the above problems,a digital process network model based on production line process constraints was proposed,and the genetic algorithm was used to optimize the machining process.This digital process design method reduces the production cycle time and improves the utilization rate of the machining center.The main research contents of this paper are as follows:(1)Construction of cylinder head process networkBy analyzing the process of the cylinder head production line,the constraints for process design are divided into process constraints based on process knowledge and engineering experience,and equipment constraints resulting from production line equipment attributes and layout.The concept of process unit which is suitable for digital technology is constructed.The process unit contains information such as processing characteristics,processing methods,and processing time.Through process constraints and equipment constraints,the constraint matrix of process unit is constructed respectively to realize the digital process network expression.(2)Optimization of cylinder head machining processBy improving the coding method and genetic algorithm operator,the permutation and combination problem under the coupling constraint is solved.By solving the process optimization problem of the cylinder head production line,it is proved that the method in this paper can optimize the machining process and reduce the bottleneck process time.(3)Application of process optimization in production lineA Plant Simulation production line simulation model was established and applied to the flexible production line of Lingang automobile engine cylinder heads.The optimized machining process is brought into the production line to verify the improvement of balance of the machining process and the reducing of cycle time.In summary,by constructing a process relationship network for the production line,a digital process design method is constructed for process balance and cycle optimization.This method is of great significance for the process digitization of flexible production lines for automotive powertrains such as engine cylinder heads.