lean manufacturing training week(英文版)(ppt 27页).ppt

1、lean manufacturing training week 3,one-piece flow,also known as “single piece flow” ideal state where items are processed and moved directly to the next process one piece at a time each processing step completes its work just before the next process needs the item and the transfer batch is one Takt

2、Time:the heart beat of one-piece flow,one-piece flow,benefits of one-piece flow: builds in quality creates real flexibility creates higher productivity frees on floor space improves safety improves morale reduces cost of inventory,one piece flow,“If some problem occurs in one-piece-flow manufacturin

3、g then the whole production line stops. In this sense it is a very bad system of manufacturing. But when production stops everyone is forced to solve the problem immediately. So team members have to think, and through thinking team members grow and become better team members and people.” Teruyuki Mi

4、noura, former President, Toyota Motor Manufacturing, North America,jidoka,Stopping the process to build in quality “A method to detect defects when they occur and automatically stop production so an employee can fix the problem before the defect continues downstream.” Poke Yoke Error Proofing,one pi

5、ece flow,redesign work processes to achieve high value-added, continuous flow. strive to cut back to zero the amount of time that any work project is sitting idle or waiting for someone to work on it. create flow to move material and information fast as well as to link processes and people together

6、so that problems surface right away. make flow evident throughout your organizational culture.,one piece flow,example: Operation A supplies parts to Operation B, which supplies to Operation C Flow that is not defined,Operation A,Operation B,Operation C,one piece flow,primary causes of deviation are:

7、 imbalanced work cycles typically person with extra time will deviate intermittent work stoppages due to lack of parts or to perform additional tasks intermittent work delays due to struggles with machines or fixtures or overly difficult or complex tasks miscellaneous issues such as “building ahead”

8、 to “buy time” for changeover, an operator leaving the line for some reason, or to stagger breaks etc,one-piece flow,Not following the rules!,one piece flow,establishing one piece flow define and dedicate the space for one piece space outlined with tape or paint to show only one piece is permitted a

9、nd a sign to further clarify this space to be physically limited (controlled) by allowing enough room for a single piece Single piece flow with visually defined agreement,Operation A,Operation B,Operation C,1 PC,1 PC,leveling,Heijunka is the leveling of production by both volume and product mix. ben

10、efits: flexibility to make what the customer wants when they want it. reduced risk of unsold goods. balanced use of labor and machines. smoothed demand on upstream processes and the plants suppliers.,leveling,In general, when you try to apply the TPS, the first thing you have to do is to even out or

11、 level the production. Once the production level is more or less the same or constant for a month, you will be able to apply pull systems and balance the assembly line. But if production levels-the output-varies from day to day, there is no sense in trying to apply other systems, because you simply

12、cannot establish standardized work under such circumstances” Fujio Cho, President, Toyota Motor Corporation,leveling,leveling by volume case study: demand varies between 800 and 1200 units manufacture at long term average and carry inventory to ensure stability of the production process in this case

13、 production would be 1000 units with minimum of 200 inventory to meet weekly targets benefits: reduce process inventories and simplify processes which reduces costs,leveling,leveling by product reduce the time and cost of changeovers so that smaller and smaller batches are not prohibitive and lost p

14、roduction time and quality costs are not significant SMED high runners predictable demand low runners high value unpredictable demand,leveling,provide your down line customers in the production process with what they want, when they want it, and in the amount they want. Just in time approach minimiz

15、e your work in process and warehousing of inventory by stocking small amounts of each product and frequently restocking based on what the customer actually takes away be responsive to the day-by-day shifts in customer demand rather than relying on computer schedules and systems to track wasteful inv

16、entory.,pull system,pull dictates when material is moved and who (customer) determines that it is to be moved use “pull” systems to avoid overproduction,pull system,pull versus push systems: defined agreement with specified limits pertaining to volume of product, model mix and the sequence of model

17、mix between the two parties- supplier and customer no defined agreement between the supplier and the customer regarding the quantity of work to be supplied and when. The supplier works at his own pace and completes work according to his own schedule.,pull system,pull versus push system: items that a

18、re shared between the two parties must be dedicated to them, this includes resources, locations, storage, containers etc and a common reference time (TAKT Time) locations are not defined and dedicated, and material is placed where there is an opening.,pull system,pull versus push system: simple cont

19、rol methods which are visually apparent and physically constraining, maintain the defined agreement. since there is no definition, or dedication, there is no clear way to understand what to control or how to control it.,pull system,provide customers what they want, when they want it, and in the amou

20、nt they want. Material replenishment initiated by consumption is the basic principle of just-in-time. minimize WIP and warehousing of inventory by stocking small amounts of each product and frequently restocking based on what the customer actually takes away. responsive to the day-by-day shifts in c

21、ustomer demand rather than relying on computer schedules and systems to track wasteful inventory.,pull systems,JIT Just in time inventory materials or supplies to arrive at a facility just when they are needed to reduce storage costs customer must specify what will be needed, when and in what amount

22、s Supplier must ensure supplies arrive at the agreed time and location,kanban,kan means “card and ban means “signal A signaling system which historically used cards to signal the need for an item other devices such as trolleys, boxes, empty spaces serve as Kanban a pull system that determines the supply, or production according to actual customer demand limits amount of inventory in the process by acting as an authorisation to produce more inventory,kanban,rules: customer processes order goods in the precise amounts specified on the kanban supplier processes produce goods in the