A Research On Machining Process Dimension And Tolerance Optimization And Production Line Balance

With developments in informatization technology and emergence of a series of informatization systems,manufacturing industry has witnessed innovations in research&development,technique,manufacture and management,together with increasingly enhanced industry levels.In-depth integration between manufacturing industry and informatization will help boost transformation and upgrading of traditional manufacturing industry to advanced manufacturing industry.BH Corporation takes the lead in piston sector,with very strong capacities in research&development,manufacture and sales of piston products,as well as gradually expanded market shares.Under the background of informatization-oriented developments for manufacturing industry,it has adopted CAPP system.Use of this system sees standardization of process design procedures,improvement in efficiency of process design and level of process management,and shortened research&development cycle for new products.However,with increasing demands for top grade pistons and occurrence of imbalance problem for production lines in manufacturing workshops,current process design methods face new challenges and the existing CAPP system cannot meet the demand.This article studies contents and conclusion below based on BH Corporation's CAPP system:(1)Analyzing present application situation of BH Corporation's CAPP system and showing existing problems:procedure dimensions and tolerances obtained are not the best;production lines are not balanced when determining process programs;process data and info cannot be statistically analyzed.Showing the reasons for problems above:lack process optimization mechanisms and conditions;lack process dimension and tolerance optimization tools.And the improvement projects are given.(2)Improving forms for process data storage and process program presentation;decomposing processes into basic process elements;using structure-based forms to store basic process element information;establishing process network to express process programs.And this provides mechanism and condition for process dimension and production line balance.Adopting functional model to describe process decomposing and process network establishing function is followed by and finally designing interface for this function.(3)Giving ways to optimize procedure dimensions and tolerances by using process dimension chain;building linear programming model to optimize process dimensions and tolerances;adopting functional model to describe process dimensions and tolerances optimization function and finally designing interface for this function.(4)Proposing to solve balance problem for machining production lines by using basic process elements;dividing parts' basic process elements into locating basis group,processing method group,clamping method group;using branch and bound method to determine each group's process program;adopting functional model to describe balance function for machining production lines and finally designing interface for this function.