Definition of Lean. Japansk produktionsfilosofi - lean manufacturing. Johann Packendorff

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1 Japansk produktionsfilosofi - lean manufacturing Johann Packendorff Definition of Lean Half the hours of human effort in the factory Half the defects in the finished product One-third the hours of engineering effort Half the factory space for the same output A tenth or less of in-process inventories Source: The Machine that Changed the World Womack, Jones, Roos

2 Lean Manufacturing is a manufacturing philosophy which shortens the time line between the customer order and the product shipment by eliminating waste. Business as Usual Customer Order Waste Product Shipment Lean Manufacturing Customer Order Waste Time Product Shipment Time (Shorter) APICS Definition of Lean Manufacturing A philosophy of production that emphasizes the minimization of the amount of all the resources (including time) used in the various activities of the enterprise. It involves: identifying and eliminating non-value-adding activities, employing teams of multi-skilled workers, using highly flexible, automated machines American Production and Inventory Control Society (APICS) is an organization for professionals working in the field of Operations Management New Paradigm: Non-Blaming Culture Management creates a culture where: Problemsare recognized as opportunities It s okay to make legitimate mistakes Problems are exposed because of increased trust Peopleare not problems - they are problem solvers PROBLEMS Emphasis is placed on finding solutions instead of who did it SOLUTIONS 2

3 What makes a manufacturing system Lean? What makes a manufacturing system Lean? 5S Programs Seiri (sort, necessary items) Seiton (set-in-order, efficient placement) Seison (sweep, cleanliness) Seiketsu (standardize, cont. improvement) Shitsuke (sustain, discipline) 9 3

4 Visual Factory Ability to understand the status of a production area in 5 minutes or less by simple observation without use of computers or speaking to anyone. 5-S 1S Sift and Sort (Organize) 2S Stabilize (Orderliness) 3S Shine (Cleanliness) 4S Standardize (Adherence) 5S Sustain (Self-discipline) What makes a manufacturing system Lean? 4

5 The Pull System Kanban Production Control At the core of JIT manufacturing at Toyota is Kanban, an amazingly simple system of planning and controlling production Kanban, in Japanese, means card or marquee Kanban is the means of signaling to the upstream workstation that the downstream workstation is ready for the upstream workstation to produce another batch of parts Kanbans and Other Signals There are two types of Kanban cards: a withdrawal card (W-Kanban) a production card (P-Kanban) Signals come in many forms other than cards, including: an empty crate an empty designated location on the floor 5

6 How Kanban Operates When a worker at downstream Work Center #2 needs a container of parts, she does the following: She takes the W-Kanban from the container she just emptied She finds a full container of the needed part in storage She places the W-Kanban in the full container and removes the P-Kanban from the full container and places it on a post at Work Center #1 She takes the full container of parts with its W-Kanban back to Work Center #2 Kanban Cards Withdrawal Kanban Card Part number to produce: M Part description: Valve Housing Lot size needed: 40 Container type: RED Crate Card number: 2 of 5 Retrieval storage location: NW53D From work center: 22 To work center: 35 Kanban Cards Production Kanban Card Part number to produce: M Part description: Valve Housing Lot size needed: 40 Container type: RED crate Card number: 4 of 5 Completed storage location: NW53D From work center: 22 To work center: 35 Materials required: Material no. 744B Storage location: NW48C Part no. B238-5 Storage location: NW47B 6

7 Flow of Kanban Cards and Containers P-Kanban and empty container Full container and P-KanbanP W-Kanban and empty container Full container and W-KanbanW Upstream Work Center #1 In-process storage Parts Flow Downstream Work Center #2 Containers in a Kanban System Kanban is based on the simple idea of replacement of containers of parts, one at a time. Containers are reserved for specific parts, are purposely kept small, and always contain the same standard number of parts for each part number. At Toyota the containers must not hold more than about 10% of a day s requirements. There is a minimum of two containers for each part number, one at the upstream producing work center and one at the downstream using work center. What makes a manufacturing system Lean? 7

8 Reducing Inventories through Setup Time Reduction Central to JIT is the reduction of production lot sizes so that inventory levels are reduced. Smaller lot sizes result in more machine setups More machine setups, if they are lengthy, result in: Increased production costs Lost capacity (idle machines during setup) The answer is: REDUCE MACHINE SETUP TIMES SMED-metoden 1. Mät hela omstället och identifiera alla enskilda moment i omstället. 2. Bestäm vilka steg som kan utföras innan- och efter att maskinen måste stannas (ej producerar). Dessa steg benämns externa steg. 3. Minska tiden maskinen måste stå stilla genom att flytta de externa stegen innan- och efter maskinen står stilla. 4. Förbättra verktyg, jiggar detaljer i maskinen samt arbetssätt för att förbättra de steg som bara kan utföras när maskinen står stilla, interna steg. 5. Förbättra de externa stegen. 6. Skriv ned de nya standarderna i arbetsinstruktioner och försäkra att att alla arbetar enligt det nya arbetssättet. What makes a manufacturing system Lean? 8

9 Effective Facility Layouts Workstations in close physical proximity to reduce transport & movement Streamlined flow of material Often use: Cellular Manufacturing (instead of process focus) U-shaped lines: (allows material handler to quickly drop off materials & pick up finished work) Traditional Process Focused Layout Jumbled flows, long cycles, difficult to schedule JIT Cellular Manufacturing Product focused cells, flexible equipment, high visibility, easy to schedule, short cycles 9

10 What makes a manufacturing system Lean? INTRODUCTION Total Productive Maintenance (TPM) is an approach to managing physical assets that emphasizes the importance of operator involvement in making equipment reliable Management has always held an operator accountable for production output. More than ever, that person is also responsible now for product quality Many factors affect how well that can be achieved, including the way in which the workplace is organized as well as the equipment s effectiveness. When several people are involved, producing quality depends on teamwork In its broadest sense, TPM is based on the idea of autonomous operator maintenance, including three sets of principles. Maintenance Engineering; Seeks to manage the equipment life cycle, from strategic asset planning, through design and construction, to operation, maintenance, and disposal. Several techniques characterize the proactive nature of maintenance engineering including: Preventive (or planned) maintenance: Planned and scheduled maintenance activities to find and correct problems that could lead to failure Predictive and condition-based maintenance: Reducing fixed-time maintenance and relying on the condition of equipment to determine maintenance activity 10

11 The prime objectives of TPM are to: Maximize equipment effectiveness and productivity and eliminate all machine losses Create a sense of ownership in equipment operators through a program of training and involvement Promote continuous improvement through small-group activities involving production, engineering, and maintenance personnel Each enterprise has its own unique definition and vision for TPM, but in most cases there are common elements in any TPM program. These have been summarized in the TPM wheel in Figure 8-1 Elements Processes Asset Strategy Continuous Improvement Team Measurement Themes Training Decentralization Maintenance prevention Empowerment Multi-skilling Resources Planning and Scheduling Systems and Procedures Figure The TPM Wheel TPM puts the power in the employee s hand. It grants workers autonomy, along with responsibility At the same time TPM recognizes that employees in one area have much to teach and learn from others The entire organization gains strength and ideas from motivated continuous improvement teams A TPM environment encourages a skills between operators and maintenance, and multi-skill training in the various crafts It can provide increase job satisfaction for operations, trades, engineering, and supervision alike 11

12 1. Awareness, Education, and For Problem Definition For Solution Development For Team Decision-making Training, cont. 9/12 Process flowcharting Customer surveys Consequences seeking Histograms Cause and effect diagrams Brainstorming Plan charts Benchmarking Normal group technique Tree diagrams Force field analysis Multivoting Pareto diagrams FMECA Pairwise ranking Statistical process control Fault tree analysis Weighted factor evaluation Scatter plots P-M analysis Failure Analysis Automated Tools Computer aided design and drafting Computer aided manufacturing Computerize maintenance management system Material management system Materials equipment planning Computer integrated manufacturing Simulation Expert systems Geographic information management system Figure Tools and Techniques for TPM What makes a manufacturing system Lean? What Is Value? "Value" is what the customer is buying Always think first about the endcustomer Who is the customer? What are they buying? Describe value using the customers' words 12

13 What Is Value Stream Analysis? Planning tool to optimize results of eliminating waste current state VSM future state VSM Lean + + = Basics Value Steam Mapping Steps Next Future State Future State Current State Original State Value Stream Scope Extended Value Stream Concept Order In-use Multi-plant/Multi plant/multi-company Launch Delivery Recycle Plant Action Action Action Action Action Action Action 13

14 Apply Five Simple Principles: Specify value from the standpoint of end customer Identify the value stream for each product family Make the product flow Perfection VALUE VALUE STREAM So the customer can pull As you manage toward perfection PULL FLOW What is the Value that Flows? Specify value from the standpoint of the end customer Ask how your current products and processes disappoint your customer s value expectation: price? quality? reliable delivery? rapid response to changing needs???? What Flows? "ITEMS" flow through a value stream In manufacturing, materials are the items In design & development, designs are the items In service, external customer needs are the items In admin., Internal customer needs are the items Analysis begins with part of a total value stream, That part of the value stream has customers too 14

15 Material Flow Icons ASSEMBLY Manufacturing Process XYZ Corporation Outside Sources C/T = 45 sec. C/O = 30 min. 3 Shifts 2% Scrap Data Box Mon. + Wed. Truck Shipment Supermarket Buffer or Safety Stock 300 pieces 1 Day Inventory Finished Goods to Customer max. 20 pieces FIFO First-In-First-Out Sequence Flow Physical Pull/Withdrawal PUSH Arrow Information Flow Icons Manual Information Flow Electronic Information Flow Signal Kanban Load Leveling Box Sequenced- Pull Ball Withdrawal Kanban Production Kanban Kanban Post Weekly Schedule Schedule General Icons Go See Production Scheduling UPTIME CHANGEOVER Kaizen Lightening Burst Operator TAKT TIME Takt Time = Effective Working Time per Shift Customer Requirement per Shift Synchronizes pace, evenly applying customer demand across the work day. Takt Time is "Beat Time"? "Rate Time" or Heart Beat" Lean Production uses Takt Time as the rate or time that a completed product is finished. If you have a Takt Time of two minutes that means every two minutes a complete product, assembly or machine is produced off the line. ( 15

16 Implementing lean Benefits of Lean Manufacturing 50-80% Waste reduction WIP Inventory Space Personnel Product lead times Travel Quality, costs, delivery 47 Setting the Foundation Evaluating your organization Management culture Manufacturing culture Lean Manufacturing Analysis Value stream (from customer prospective) Headcount WIP Inventory Capacity, new business, supply chain 48 16

17 Tools of Lean Mfg/Production Waste reduction Full involvement, training, learning Cellular mfg Flexible mfg Kaikaku (radical change) Kaizen (continuous improvement) & standard work 5S Jidoka (autonomation) Poka-yoke (visual signals) Shojinka (dynamic optimization of # of workers) Teien systems (worker suggestions) 49 Tools (cont.) Continuous Flow (10% - 25%) SMED (Shingo) Andon Takt time Line balancing Nagara (smooth production flow) 50 Tools (cont.) Customer pull (10%- 25%) Just-in-time Kanban 51 17

18 Henry Ford - Standards To standardize a method is to choose out of the many methods the best one, and use it. Standardization means nothing unless it means standardizing upward. Today s standardization, instead of being a barricade against improvement, is the necessary foundation on which tomorrow s improvement will be based. If you think of standardization as the best that you know today, but which is to be improved tomorrow - you get somewhere. But if you think of standards as confining, then progress stops. Henry Ford, 1926 Today & Tomorrow Standardized Work Captures best practices Posted at the work station Visual aid Reference document work sequence job layout time elements safety Developed with operators Basis for Continuous Improvement Other Tools Visual Factory Error Proofing Quick Change-over Total Productive Maintenance 18

19 What makes a manufacturing system Lean? 19