The Improvement Of Production Efficiency In C NC Production Unit Based On "Eliminate Seven Waste" Concepts In Lean Production

Lean production theory originated from Toyota Corporation of Japan.With its extensive research and application in manufacturing companies,Lean has become a common practice for enterprises to improve efficiency.At present,the international manufacturing community widely agrees that Industry 4.0 is an effective method for enterprises to cope with future challenges.As one of the four modules for building a smart factory in the future,the importance of Lean for enterprises is becoming more and more obvious,in a market seeking for products diversity and smaller batch.C hina has published the C hina Manufacturing 2025 plan and set the goal of transforming from a manufacturing power of quantity to quality.Lean is also an important foundation and guarantee for accelerating the transformation and upgrading of the manufacturing industry.The gap between C hina's manufacturing industry and the world's advanced manufacturing capabilities lies not only in production equipment but also in the management aspect.The ultimate goal of lean is eliminating waste from production with the reduction of three types of waste: muda,muri,and mura,to expose problems systematically and to use the tools where the ideal cannot be achieved.The lean production unit is the prototype and foundation for the smart factory in the future.The research on the efficiency of the production un it based on the seven wastes of lean proved to be beneficial on accelerating the response speed of the enterprise to the market demand,improving the production efficiency,reducing the manufacturing cost,and improving the enterprise efficiency.By applying lean in the new Industry 4.0 era,management of the enterprise could be hugely improved.Firstly,This paper begins with an analysis of the core ideas of lean production and elaborates on the principles and risks of Lean's seven wastes' generation,and the efficiency improvement methods and tools based on lean production.For example,production value stream analysis,production cycle time calculation,balanced production,establishment and promotion of standardization systems,pull production,and full participation in continual improvement.Secondly,this paper takes a CNC production unit of company C as the research object,and analyzes the current resource and production status,compares with the future production demand of the production unit.The production data was collected to draw a production value-added flow chart.With the help of the flow chart,the problems of the production unit in process technology,unit layout,logistics planning,equipment support,plan management,etc.were systematically analyzed and the wastes in the production unit are sorted out.In order to better achieve the goal of improving production unit efficiency,this paper selected the most important and influential types of wastes as the core research subjects.Then,based on the existing defects,major wastes and future production requirements of the production unit,a four-step lean production unit improvement plan was formulated under the lean guidance.These four steps are target setting,unit design,unit control and a utonomous operation.A lean improvement team was built to set the goal of unit improvement,to detail and carry out the work plan,and to liaise the IT support.The main production process was rebuilt,optimized and solidified by means of process optimizat ion,continuous improvement and standardization.Finally,by eliminating the four kinds of waste: waiting,movements,defects and transport in the core production process,the goal of improving production efficiency was achieved.This paper also compared a nd analyzed the production performance indicators and management status before and after the improvement,and presented and summarized the research results of the efficiency improvement of production units.At last,the research practice of this paper illustrated how to establish a lean production unit,eliminate production waste,improve production efficiency and form a complete set of plans.Other production units in company C and related manufacturing enterprises can use this practice as a guidance,to build and improve a CNC production unit and achieve lean production.