价值流程图VSM.ppt
Value Stream Mapping Train-the-Trainer,Information For A Process Data Box(to be collected on the shop floor),Cycle timeChangeover timeProcess reliability(uptime)Scrap/Rework/Defect rateNumber of product variationsNumber of operatorsProduction batch sizesWorking time(minus breaks)Pack size,Typical Steps to Complete a Current State Drawing,Document customer informationComplete a quick walk through to identify the main processes(i.e.,how many process boxes)Fill in data boxes,draw inventory triangles,and count inventoryDocument supplier informationEstablish information flow:how does each process know what to make next?Identify where material is being pushedQuantify production leadtime vs.processing time,Many shops have a combination of repetitive and non-repetitive products(indicating product families)Product families might be difficult to see focus on machines/operations and work content timeEngineering might be included in the information flow for leadtime impact,etc.Pitch is typically arbitrary to the managerEmployment of pitch requires detailed knowledge of work content and routings for jobs,Frequently Asked Questions:Make to Order and Engineer to Order Shops,FAQ:Distribution Centers Example,(Information flow on top),I,I,I,I,I,FAQ:Parallel Manufacturing Flows,Keep it simple,and make sure to leave room for the data boxes!,FAQ:Including Subassemblies,Focus on major subassemblies firstSelect one or two which might represent different types of situationsGeneric vs.specific to the product familyOutsourced tasks within assemblyFollow the format for parallel flow,and always include the main assembly process!For large fabricating and assembly operations,consider maps for each major subassembly with a“macro map”indicating the entire product family,FAQ:Do We Really Have a Supermarket(or FIFO lane)?,Supermarkets(and FIFO lanes)control production between points of flow without a written schedule.What is the trigger for production in this area of the value stream?Is the upstream process overproducing?If there is a scheduling system present outside of a pure pull,chances are that there is no supermarket.,FAQ:Outsourcing,3 Days,60 min.,2 days,.7 days,FAQ:Long Processing Times vs.Production Leadtimes,8 hours,8 hours,3 days,1 day,FAQ:Cycle Times vs.Work Content,Work content is important to understand costs and in balancing flowConsider all machine and manual work content,regardless of the cycle timeAccumulate all parallel operations in the processing timeline,=5,Cycle Time=30 secWork Content 150 sec.,FAQ:Different Changeover&Cycle Times,etc.,Current state mapping might uncover:Several different machines performing the same operationDifferent products within the family with different data box characteristics for a specific processCapture the range of values as opposed to an average value,FAQ:Mapping Final Inspection/Repair/Rework,Judgment counts!Minimal repair/rework might be captured as a data attribute at the final step.If nearly every part needs assessment or extra work,consider a separate process box.,FAQ:Supplier Data Boxes,Data attributes are dependent on the value stream and supplier.Minimum information might include:,L/T=3 weeks,Batch=3 Tons,Min.Batch=2T,2%Scrap,FAQ:Pull Within an MRP Environment,A combination push and pull is usually just a push system!Multiple production triggers typically lead to overproduction.,FAQ:Assemble-to-Order Options in a Future State,Finished goods supermarkets can be expensive in value streams which have many finished part numbers within a product familyTo minimize inventory costs,try to find the upstream location where the value stream has very few variations and consider a supermarket of WIP at that point.Customers orders can“drop”to this location,with FIFO lanes controlling production into shipping.,FAQ:Assemble-to-Order Options in a Future State,Customer Orders,OXOX,FAQ:Why Not Just Start Pulling Tomorrow?,Initiating a pull system without first attempting to flow will result in lots of supermarkets,and may increase your inventory levels.Design your future state with the following sequence:Flow wherever you can(while still pushing)Produce to the TAKT(while still pushing)Implement a pull system,FAQ:Administrative Mapping:Part 1:Integrated,Include functions such as engineering,purchasing,and order entry for product families which have routine activities prior to schedulingPlace the process boxes between the customer and the scheduling functionMinimize the data collection to the basics of cycle time or quality,and document the impact on leadtime,FAQ:Administrative Mapping:Part 2:Separate Maps,Better for redesigning overhead and administrative support areas touching value streamsOrder processingWarranty activitiesJob quotesNot useful for activities outside a value streamData boxes must have attributes focusing on cost,quality,and service“Inventory”is typically paperworkInformation flow is typically informal,
