LEAN MANUFACTURING PRINCIPLES

LEAN MANUFACTURING PRINCIPLES
© NCSU IES LEAP Group Rev 3/04

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Lean Enterprise Advancement Program
Mission - Improve the quality, cost and delivery of North Carolina manufacturing firms to improve their competitiveness by understanding and implementing lean enterprise business systems based on TPS model.

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Key Principles of Lean Thinking
VALUE - what customers are willing to pay for VALUE STREAM - the steps that deliver value FLOW - organizing the Value Stream to be continuous PULL - responding to downstream customer demand PERFECTION - relentless continuous improvement (culture) --- Lean Thinking, Womack and Jones, 1996 Ask the audience their definition of Lean Manufacturing, or what does it mean to be lean? After various responses, introduce the five key principles of lean manufacturing, as detailed in the Womack and Jones book, Lean Thinking. Try to relate each principle to not only their industrial/work lives, but also to their lives as consumers. Some people may think that lean manufacturing is all about cutting jobs and laying people off. It is important to note that lean manufacturing is implemented by organizations that want to improve their operations, grow the business, and increase sales, resulting in better long-term health of the company. Lean manufacturing is a growth strategy. Instead of laying off people, it is about taking freed-up resources and reinvesting, or redeploying them in the organization.

Defining Lean Lean is: “A systematic approach to identifying and eliminating waste (non-value added activities) through continuous improvement by flowing the product at the pull of the customer in pursuit of perfection.” The MEP Lean Network

Lean Goals- TPS “True North”
Zero defects 100% value-add Lot size of one Pull of the customer TSSC

LEAN MANUFACTURING Why Become Lean? PQCDSM
Improve Customer Satisfaction Increase Sales and Profits Insure Long-term Health of Company Survival Create Sustainable Competitive Advantage PQCDSM stands for: Productivity Quality Cost Delivery Safety Morale You may want to ask the audience for definitions, which will probably be similar to the ideas above. The driving force (no pun intended) behind the Toyota Production System is the satisfy the customer through improved quality, cost and delivery. If we can achieve one or some combination of these goals, then we have a better chance of increasing sales and profits, thus insuring the long-term health of the company. The idea of a sustainable competitive advantage is one where you create an advantage or benefit that is not easily duplicated by competitors.

Typical Results from Lean Conversions
Percentage of Benefits Achieved Lead Time Reduction Productivity Increase WIP Reduction Quality Improvement Space Utilization These are typical results from a lean conversion. These types of results are often seen on a localized basis immediately after a particular lean improvement activity is completed. It takes a period of months into years for an organization to tie individual improvements together and truly realize bottom-line financial improvement. Flexibility Skill Enhancement Visual Management

LEAN MANUFACTURING Where has Lean been successfully implemented?
Automotive Industrial Products Furniture Textiles and Apparel Printing and Packaging Consumer Products Service Industries Military Healthcare Even though Lean Manufacturing originally began with the automakers (Ford and Toyota), many other industries and organizations have successfully implemented lean. Here you can give your own examples of the companies and industries we have worked with. A short list includes: Industrial Products – Ingersoll-Rand, Carrier, Duff-Norton, Danaher, Johnson Controls, Black and Decker, Maytag Furniture – Hickory Chair, Ethan Allen, Cochrane, HON, Hickory Tree, Henredon, Merillat Textiles and Apparel – Sara Lee Intimate Apparel, Sara Lee Hosiery, National Textiles, Elastic Fabrics of America Printing and Packaging – Northstate Carton, Pharmagraphics, RJR Packaging Consumer Products – Scott Vending/Catering Products Service - Banks Military – Naval Air Depot at the Marine Corps Air Station, Northrup Grumman Newport News Healthcare – Mission Hospital, Gaston Hospital

Developing a Lean Factory
The Goal and Getting There from Here The Goal - Lean Throughout the Entire Enterprise Set Aggressive Improvement Goals Measurements of Existing Operations Recognize Current Problem Areas Apply the Lean Production System Concepts Commit to the Continuous Improvement Process Just do it! I like to compare this to the sequence of a lean continuous improvement activity. We are trying to become lean throughout the entire organization, not just in manufacturing, and not just in our own facility. Lean practices extend throughout the entire facility and throughout the entire supply chain. Setting goals is one of the first steps. Taking current measurements and observations of what is actually happening. The measurements will reveal problems and improvement opportunities. Apply the concepts and ideas we will be introducing and discussing. Commit to the process. Take the action and make the improvements now!

Value Added/Non-value Added
ANY ACTIVITY THAT PHYSICALLY CHANGES THE MATERIAL BEING WORKED ON (not rework/repair!) Machining Knitting Drilling Spreading/Cutting Assembly Dying Painting Sewing Non-value added: ANY ACTIVITY THAT TAKES TIME, MATERIAL, OR SPACE BUT DOES NOT PHYSICALLY CHANGE THE MATERIAL Sorting Stacking Counting Checking Try to relate this to the industry/processes that the audience has experience with. Most of these examples are for metal working and textiles, so you may want to mention others. For NVA, you may want to exclude inspection at this time, because it will come up as a discussion point at a later time.

Lean = Eliminating the waste
Typically 95% of Total Lead Time is Non-Value Added!!! Value added 5% Non-value added 8 Wastes Overproduction Excess inventory Defects Non-value added processing Waiting Underutilized people Excess motion Transportation Before this slide comes up, ask the audience to guess the percentage of value-added time for any manufacturing or administrative activity. They are usually surprised to learn that it is typically less than 5%, which is substantiated when time observations and VA/NVA analyses are performed. When Toyota first developed the TPS, they realized that if they could identify these sources of waste, then they would have a better chance at reducing or eliminating waste. Go through each source of waste and discuss examples with the audience. Ask the audience if they are familiar with any additional sources of waste. A good one to add is work-related injury, which results in lost-work time.

Value Stream Mapping A simple diagram of every step involved in the material and information flows needed to bring a product from order to delivery. Value stream maps can be drawn for different points in time as a way to raise consciousness of opportunities for improvement. Value Stream Mapping is another high-level tool used to identify and eliminate waste. - Lean Lexicon

This is the current state map for Acme Stamping from Learning to See
This is the current state map for Acme Stamping from Learning to See. Point out the information flows, material flows, process boxes, data boxes, inventory and timeline. Contrast the difference between the lead time and the processing time. - Learning to See

Lean Production System
Goals - highest quality, lowest cost, shortest lead times Just-In-Time continuous flow takt time/pace pull system triggers Involvement Jidoka separate man & machine work identify abnormal conditions poka yoke Heijunka Standardized Work Kaizen We will be discussing the goals first – satisfying customer demand. This is paramount to the Lean Production System. Stable Manufacturing Process

Toyota’s Philosophy Customer first
People are the most valuable resource Kaizen (continuous improvement) Shop floor focus These are the main tenets of Toyota’s production philosophy. By putting the customer first in everything they do, they will increase sales and profits, and insure the long-term health of the company. Employees are located in the center of the model, and Toyota refers to their employees as the lifeblood of the Toyota Production System. Discuss the importance Toyota puts on their employees health and development. Kaizen is a way of life for Toyota. I like to discuss the number of Kaizens turned in at the Toyota plant in Kentucky (97,000 for 2001). The Lean Production System is one that is directed top-down, and implemented from the bottom-up. It is very important to go to the floor and see what is going on, rather than making changes from an office, away from the floor.

Goals - highest quality, lowest cost, shortest lead times Just-In-Time continuous flow takt time/pace pull system triggers Involvement Jidoka separate man & machine work identify abnormal conditions poka yoke Heijunka Standardized Work Kaizen This is where we will begin our discussion. We will develop Stability, then Just-in-Time, then Jidoka, then Standardization and finally Involvement. Stable Manufacturing Process

Stability The Four Ms Operations safely carried out with all task organized in the best known sequence and by using the most effective combination of resources huMans Materials Methods Machines This slide was originally titled Standard Work, but it works equally as well for stability. It is important to make sure that we have a stable manufacturing operation to make improvements that will be sustained. Humans – Training, Safety, Morale, Health and Attendance. Materials – Good quality materials free of defects, received in a timely manner. Methods – Procedures and standards that exist, are correct and are enforced. Standardized Work is a big part of this. Machines – Machines and processes that are available, run efficiently and run good quality product.

Stability The 5S’s Sort Stabilize Shine Standardize Sustain
Keep only what is needed in your area Stabilize A place for everything and everything in its place Shine Clean up the workplace Standardize Develop system (rules) to maintain what has been done Sustain Self discipline to maintain established procedures 5S, also know as workplace organization, is a big part of manufacturing stability. It is the foundation for many of the more advanced lean manufacturing concepts. The basic premise is that a safe, clean, and organized work environment will be more efficient and pleasant. There have been many cases where 5S must be completed before other lean activities can be completed. It is important to be able to “see the flow” in order to make improvements. Each S corresponds to a Japanese work, but I try not to get too deep into it. It is interesting to note, that Toyota has eliminated one of the S’s. Have the audience guess which one. Toyota has removed the last S, sustain, because continuous improvement is such a part of their culture, and they do not need to remind people to sustain.

Stability The 5S’s - Before

Stability The 5S’s Styrofoam has been cut out to provide a specific location for each tool required in a changeover process. Each location is also labeled, so at a glance a missing tool can be quickly identified.

Stability The 5S’s Notice the signs with pictures above each aisle in the upper left-hand picture. Also, pallet positions are outlined and labeled as either TO BE BACKWOUND or READY TO SHIP. Courtesy of National Textiles

Stability Visual Controls
Visual Controls are simple signals that provide an immediate understanding of a situation or condition. They are efficient, self regulating, and worker managed. Examples include: Pictures, diagrams Color coded dies, tools, pallets Lines on the floor to delineate storage areas, walk ways, work areas, etc. Improved lighting Visual Controls are designed to clearly communicate information about production status, quality, safety or procedures. The goal is for someone who is not familiar with the area to be able to come in and understand the status in a short period of time.

Stability Visual Controls
This is a visual control for a work procedure that is posted in the work area. It is very large and visual, so when you enter the area, you cannot miss it. In addition, there is a signal light hanging indicating some kind of status (we do not know).

Stability Plant Layout Shipping Q C Raw Stock Receiving Q C
Screw Machine Shear Stamp Lathe Drill This is a traditional factory layout, where most of the products and parts move through most of the factory. For example, the red product stops in receiving, passes through QC, stops in raw stock, stops in the screw machines, backs up and stops in the mills, passes through lathes, stops in drills, backs up again and stops in grind, stops in finish, stops in parts stock, assembly, QC and shipping. Other products follow different paths, but still travel a lot around the factory. Assembly Brake Mill Weld Grind Finish Parts Stock

Market Demand = 220,000 Units Per Year
Stability Cellular Layout Lathe Mill Inspect Drill Test Pack 1 2 3 4 5 10 9 8 7 6 27 Seconds 27 Seconds Contrast the traditional layout to a more flexible, cellular layout. Raw material enters the cell, pass through the necessary processes, and finished product leaves the cell. Workers share tasks, flow is improved, inventory is reduced and floor space is reduced. Definitely, a much more flexible layout. Market Demand = 220,000 Units Per Year Takt Time = 27 Seconds

Courtesy of Duff-Norton, Charlotte, NC
Stability Cellular Layout This is an example of a cellular layout. Before, many of these machines and processes were located throughout the plant, covering much more floor space. Courtesy of Duff-Norton, Charlotte, NC

Stability Total Productive Maintenance
Total Productive Maintenance (TPM) is a series of methods to keep equipment running The goals of the TPM process include: Develop people who are equipment-knowledgeable Create well-engineered equipment: building in safety and quality Create an environment where enthusiasm and creativity flourish Maximize equipment productivity and capacity as measured by Overall Equipment Effectiveness (OEE) The final topic in the Stability section is TPM, or Total Productive Maintenance. TPM is a proactive approach to managing the maintenance of machines and equipment by doing the following: The goal of TPM is to build a robust enterprise by maximizing production system efficiency (overall effectiveness). TPM addresses the entire production system life cycle and builds a concrete, shopfloor-based system to prevent all losses. Its aims include the elimination of all accidents, defects and breakdowns. TPM involves all departments, from production to development, sales, and administration. TPM achieves zero losses through overlapping team activities. As defined in the book, TPM for Every Operator.

Stability OEE = Availability × Performance Efficiency × Rate of Quality Availability When or how often do you lose total availability of your equipment? How long are your set-ups? Does your equipment break down frequently? Performance Efficiency Does your equipment start and stop a lot? Does your equipment run at 100% of its designed speed? Rate of Quality Do you manufacture quality products? Are your processes repeatable? TPM uses an index called overall equipment effectiveness (OEE) to clarify the impact of the six big losses and to measure the overall health of equipment. Taking the six big losses into account and calculating OEE typically yields a figure of 50 to 60 percent. In other words, most plants are only using machines to half of their potential. The Six Big Losses that downgrade Machine Effectiveness: Related Losses Setup and Adjustment Breakdowns Related Losses Idling and Minor Stoppages Reduced Speed Related Losses Startup Defects and Rework

Sample Daily Operator PM
 1. Check coolant level through clear Plexiglas  2. Check heat exchanger fans (strings should be moving)  3. Check servo drive fans (string should be moving)  4. Check heat exchanger air filter (change when dark)  5. Check servo drive air filter (change when dark)  6. Check way lube reservoir (add when low)  7. Check main motor air filter (change when dark)  8. Check main motor cooling fan (string should move)  9. Check mist collector motor and air filter (change when dark)  10. Check bar feeder hydraulic motor air filter  11. Check bar feeder hydraulic oil level (add when low)

Summary – Stability in Manufacturing Processes
Developing a Lean Factory Summary – Stability in Manufacturing Processes 4Ms 5S Visual Controls Plant Layout Total Productive Maintenance

Goals - highest quality, lowest cost, shortest lead times Just-In-Time continuous flow takt time/pace pull system triggers Involvement Jidoka separate man & machine work identify abnormal conditions poka yoke Heijunka Standardized Work Kaizen Stable Manufacturing Process

Just-in-Time Pull System
Pull System is a flexible and simple method of controlling/balancing the flow of resources. Eliminating waste of handling, storage, expediting, obsolescence, repair, rework, facilities, equipment, excess inventory (work-in-process and finished). Pull System consists of: Production based on actual consumption Small Lots Low inventories Management by Sight Better Communication This is one of the most important concepts in a lean transformation. As opposed to pushing the product through the value stream, we want to produce only when the downstream process has consumed what we have produced. In essence, we want to produce based only on customer demand. Obviously, we would like to create continuous flow throughout the entire value stream, but due to a number of reasons, this is not always possible. Therefore, where continuous flow is not possible, we need to establish pull signals to link non-continuous processes and maintain flow.

Just-in-Time Pull System Kanban
- A signal to indicate when more parts are needed (Order or Produce) - Card, empty Bin, In Process Kanban (IPK) on plant floor Give examples of different kanban signals that different companies have used. Typically it is a card, or an empty location on the floor or shelf. However, there have been some creative examples, such as Hickory Chair, where the furniture upholstery department signals their demand to the frame department by dropping a colored piece of wood down a tube that goes to the frame department. So instead of overproducing frames, tying up money and space, they only produce based on actual demand.

Just-in-Time Pull System
This is an example of a pull system at Ingersoll-Rand in Southern Pines, where they manufacture hoists, tools and pneumatic valves. This board is located in one of the machining areas, which produces for the assembly area. Each orange card signifies a batch of parts that has been consumed in the assembly department. As the cards are returned from assembly, they are loaded onto the board from the bottom slot up. Each column represents a different part, and each slot is colored green, yellow, or red. As the cards are dropped into the slots, they move from green slots, to yellow slots, to red slots. When the green slots are filled, assembly has an adequate supply of parts. As they move into the yellow and red slots, machining should begin to run the parts. The top part of the board shows visual queues on where particular part orders are, based on which outside process they were sent to. Also, each column is color coded based on the type of material that the part is made from. Courtesy of Ingersoll-Rand Co., Southern Pines, NC

Just-in-Time Supermarket Analogy
A carton of milk is removed from shelf A stock person restocks the empty location, but only brings what shelf can accommodate the supermarket combines visual control, pull system, Kanban, 5S I like to tell the story that when some of the Toyota people visited Ford to learn about mass production after WWII, they didn’t learn as much in the factory as they did in the American supermarket. The reason was that they could not apply many of the traditional mass-production techniques in Japan because their economy and market was much smaller, which required smaller quantities of a higher variety of models. However, when they visited the American supermarket, they saw pull systems in action with the restocking of grocery store shelves. When the stock person went to stock the shelves, they refilled only what had been consumed. In addition, the visual aspect of the dairy case, with it’s FIFO lanes and visual aspects, also displayed the demand for particular products. Signs hung above aisles directed shoppers exactly to the products they were looking for. Finally, clean, organized supermarkets provided the shopper with a pleasant shopping experience. Toyota decided that they could apply these techniques into their manufacturing operations.

Just-in-Time Quick Changeover (Set-up Reduction)
Single Minute Exchange of Dies (SMED) a series of techniques for changeovers of production machinery in less than ten minutes (single digit minutes) Set-up Reduction Program Goals To achieve smaller lots To maintain consistent quality To minimize inventory To reduce lead times To address frustration of setup personnel Shigeo Shingo pioneered many techniques aimed at reducing the changeover time for large stamping presses in the early days of Toyota. Through simple, low-cost solutions, he was able to reduce changeover times from hours down to less than ten minutes. Hence, the name Single Minute Exchange of Dies.

Just-in-Time Basic SMED Principles
Identify internal vs. external changeover tasks Analyze each task’s real purpose and function Focus on no/low cost solutions Aim to eliminate changeover time The classic example of changeover reduction is a NASCAR race car as it stops during a race for the pit stop. Imagine the time the car is in the pit area as the internal time (the time the machine is down for changeover). Imagine the time the car is on the racetrack racing as external time (the time the machine is running good parts). The goal is to identify the internal and external elements and try to convert as many internal elements to external elements. Then try to streamline and reduce the waste on all elements. The ultimate goal is to completely eliminate changeover time. Ask the audience who is a NASCAR fan, and who their favorite driver is. Ask what the typical pit stop time is for a full pit stop. Discuss some of the techniques that pit crews use to reduce the pit stop time. Some examples include lug nuts glued to the wheels, one-pump jacks, high-volume gas cans, peel-off windshields, etc.

Just-in-Time Positioning Pins Positioning Pins
This is one example of a stamping press where plates can be aligned quickly and absolutely using positioning pins. The key aspect of changeover reduction is repeatability. Positioning pins on press plates are used to quickly position/center the die. No need to make adjustments – the pin “marks the spot.” Positioning Pins

Pear-Shaped Hole Method
Just-in-Time No/Low Cost Solution: One-Turn Methods Pear-Shaped Hole Method Tighten Here With pear-shaped bolt holes, we cut a bolt hole in the shape of a pear. When we want to remove/replace the part, we loosen the nut with one turn, move the bolt from the narrow end of the pear-shaped hole to the wide end of the hole, then lift the part over the bolt – the bolt itself is not removed. When the part is replaced, this set of motions is replaced. Some other examples of one-turn methods include U-slots, clamps, and split-thread bolts. Attach and Remove Here

Just-in-Time No/Low Cost Solution: One-Turn Methods Speed Nut
Speed nuts, wing nuts and quarter turns are just some examples of various alternative fasteners that will reduce the amount of time it takes to tighten/loosen fixtures during a changeover.

Just-in-Time No/Low Cost Solution: One-Turn Methods Wing Nut Method

Just-in-Time No/Low Cost Solution: One-Motion Methods Cam Method
Other types of functional clamps are based on one-motion methods. Just as the name implies, one-motion methods allow us to tighten/loosen a fastener with one motion. Examples of one-motion methods include spring stops, wedges, magnets, vacuum suction, and cam/clamp devices. This is an illustration of a simple cam/clamp device. When the lever is in the position shown, the part is clamped in place. When the lever is released, the part can be removed. A third type of functional clamp use interlocking methods to secure a part. By interlocking, we mean that two parts are joined (fitted) together without using a fastener.

Just-in-Time Quick Changeover
Not quick: Must heat molds and plates before changeover Quicker: Test stand with hot plates to pre-heat molds and plates This is a mechanism developed for pre-heating molds and plates for a bra cup molding machining. Previously, when the changeover was done, the machine had to heat the molds and plates to the appropriate temperature before production could begin. With this assembly, the plates and molds can be pre-heated, saving 25 – 30 minutes of changeover time. This is a low-cost solution, made of a fabricated metal stand, wire-mesh, and hot plates. Courtesy of Playtex Panama, Santo Domingo, DR

Just-in-Time Continuous Flow - Batch Size Reduction
The best batch size is one - one piece flow, or make one and move one! Benefits: Reduces WIP, lead time, cycle time, etc. and improves quality In the first two rounds of the simulation, the batch sizes varied based on the work station. Clearly, we can benefit by standardizing the batch sizes moving through the area. In addition, we may want to reduce the batch sizes. Ultimately, we would like to get to a single-piece batch size, also known as single-piece flow. For processes where sets have to match up, single-set flow can be used. For example, where bearings are manufactured, batches of ten must be run, in order to optimize the process of matching ball diameters with inner and outer races. Another example might be where it is important to keep left- and right-hand components mated. The benefits of reducing batch sizes include reduced inventory, shorter lead times, reduced handling, improved quality, and reduced floor space.

Just-in-Time • Batch & Queue Processing • Continuous Flow Processing A
10 minutes 10 minutes 10 minutes Lead Time: 30+ minutes for total order 21+ minutes for first piece 12 min. for total order 3 min. for first part Process B A C • Continuous Flow Processing This is a good graphic depicting the benefits that can be achieved by making the transition from batch flow to continuous flow processing. It is important to note that this transition cannot typically be done overnight, and that batch size reduction, layout changes and machine setup reduction will be necessary.

GOAL: Produce to Demand
Just-in-Time Takt Time = Demand Rate Work Time Available Number of Units Sold Takt Time = GOAL: Produce to Demand

Summary - Just-in-Time
Developing a Lean Factory Summary - Just-in-Time Pull Systems/Kanban Point Of Use Storage Quick Changeover/Setup Reduction Continuous Flow Takt Time

Goals - highest quality, lowest cost, shortest lead times Just-In-Time continuous flow takt time/pace pull system triggers Involvement Jidoka separate man & machine work identify abnormal conditions poka yoke Heijunka Standardized Work Kaizen Jidoka means “autonomation” in Japanese. Autonomation means machinery with a human touch. The purpose of Jidoka is to develop processes that either alert you when a mistake has been made, or prevents a mistake from being made in the first place. Jidoka includes topics such as quality, mistake proofing and problem-solving. Stable Manufacturing Process

Jidoka Quality at the Source
Source Inspection: Operators must be certain that the product they are passing to the next work station is of acceptable quality. Operators must be given the means to perform inspection at the source, before they pass it along.

Jidoka Quality at the Source Source Inspection at Molding
This is a bra cup molding machine. Every 12 cycles, the machine automatically shuts down, which allows the operator time to inspect the previous lot. After the inspections are completed, the operator resets the counter and restarts the machine. Even though this method doesn’t prevent the operator from producing bad quality product, it gives the operator the time and tools necessary to insure good quality at the source. If there is a quality problem, then you need only rework or scrap 12 bad units, instead of 1,200 bad units. Courtesy Sara Lee Intimate Apparel, Villanueva, Honduras

Jidoka “Bull’s Eye” for checking package size
This gauge is used at the end of spinning frames to insure that the yarn “package” sizes are the acceptable size. Any package that has a diameter smaller than the red circle is deemed off-quality. Courtesy of National Textiles

Jidoka Quality at the Source
Samples or established standards are visible tools that can be used in the cell for such purposes Process Documentation defining quality inspection requirements for each work station may need to be developed In the early rounds we have used written instructions and photographs to instruct the assemblers on proper technique. Ask the audience what the best tool would be to show someone how to assemble a part. By now, many of them may have already brought up the idea of samples. If you had given the final assembler a sample unit to work from in round 1, there probably would not have been as much confusion.

Jidoka Poka-Yoke (Mistake Proofing)
A Poka-yoke device is any mechanism that either prevents a mistake from being made or makes the mistake obvious at a glance. Poka-yoke devices: - perform well when corrective action involves trying to eliminate oversights and omissions. - can reduce the time and cost of informative inspection to near zero. - used with source inspection, can ensure that proper operating conditions exist prior to actual production. Hold up a slightly deformed part B or D from the simulation. Ask the audience which part it is, and if it is good quality. Ask the audience how to simply and easily correct the defect. Some of the responses may include jigs, molds, fixtures, etc. Let them know that by simply squaring the joints on the table, you have insured a good quality part. Ask the audience for some examples of poka-yoke devices in their operations.

Examples: Fueling area of car has three mistake-proofing devices: 1.filling pipe insert keeps larger, leaded-fuel nozzle from being inserted 2.gas cap tether does not allow the motorist to drive off without the cap 3.gas cap is fitted with ratchet to signal proper tightness and prevent over-tightening.

Notice the white PVC pipe with the bell mounted on it hanging from the ceiling. The pipe is hung level with the door opening, so if a fork truck with a load that is too high tries to enter, it hits the pipe and rings the bell. This early warning prevents the fork truck driver from driving through the doorway, preventing injury to the operator and damage to the structure or equipment.

Jidoka Andon A visual management tool that highlights the status of operations in an area at a single glance and that signals whenever an abnormality occurs. An andon can indicate production status (for example, which machines are operating), an abnormality (for example, machine downtime, a quality problem, tooling faults, operator delays, and material shortages), and needed actions, such as changeovers. An andon can also be used to display the status of production in terms of the number of units planned versus actual output. --- The Lean Lexicon

Jidoka Andon Depending on the bulb lit, a different situation requires attention. Courtesy of Sara Lee Intimate Apparel

Jidoka Identifying Problems
“When I was asked to attend the general manager’s meeting the first time, I was happy to attend because I thought I could say that there were no problems in my department. And I said so when it was my turn to report. Then, this General Manager from Toyota looked straight into my eyes and said, ‘Steve, when you say you do not have a problem, that is the problem.’” At this moment, I realized that in order to succeed in this business, I have to change my way of thinking totally. --- From JIT Kakumei no Shogeki by Kiyoshi Suzaki, p. 14. The Toyota Production System is very problem-solving oriented. Instead of concealing problems with large amounts of inventory and other wastes, Toyota seeks to find problems, so they can develop solutions. It is similar to the analogy of inventory being similar to the water level in a lake. As you lower the inventory (water level), you start to expose problems (trees and rocks) that must be solved before lowering the water any more.

Jidoka Identifying Problems - Trystorming Before After
This is the epitome of problem-solving and continuous improvement. One of the problems encountered in yarn spinning is dirty packages. As the packages are doffed off the spinning frames, they are moved down a belt for removal. As they move along the belt, they come in contact with dirty plates, which contaminate the product. The team developed a method to clean the plates using a simple, inexpensive mop head that was modified to travel along the conveyor plates pushed by the doffing mechanism. The “Swifter” as the group calls it, was very cost effective, yet will save the cost of reworking dirty packages. Courtesy of National Textiles

Jidoka A3 example from W.P. Hickman.

Developing a Lean Factory
Summary - Jidoka Quality at the Source Poka Yoke Andons Effective Problem Solving

Goals - highest quality, lowest cost, shortest lead times Just-In-Time continuous flow takt time/pace pull system triggers Involvement Jidoka separate man & machine work identify abnormal conditions poka yoke Heijunka Standardized Work Kaizen The last tenet we will discuss will be Standardization. The topics include Heijunka, Standardized Work and Kaizen. Stable Manufacturing Process

Standardization Standardized Work
Establishing precise procedures for each operator’s work in a production process, based on three elements: Takt time, which is the rate at which products must be made in a process in order to meet customer demand. The precise work sequence, in which an operator performs tasks within takt time. The standard inventory, including units in machines, required to keep the process operating smoothly. Takt Time – The rate of customer demand. Work Sequence – The best agreed-upon steps to perform a process. Standard Inventory – Also known as Standard WIP, this is the minimum amount of inventory required for everyone to begin work. It is also a control mechanism designed to insure that the proper amount of inventory is in the correct location. --- The Lean Lexicon

Standardization This is a good example of a standardized work sheet. It includes takt time, work sequence, and standard inventory.

Standardization Standard Work Board
It is important to display standardized work for communication and training purposes. Courtesy of Ingersoll-Rand Co., Southern Pines, NC

Standardization Takt Time = 10 seconds

Standardization Heijunka
Leveling the type and quantity of production over a fixed period of time. This enables production to efficiently meet customer demands while avoiding batching and results in minimum inventories, capital costs, manpower, and production lead time through the whole value stream. Heijunka is the Japanese term for production leveling. Instead of producing in large batches, it is important to level the production mix and volume. This way, flow is improved and smaller demand signals are transmitted up the value stream. At Toyota you will see Camrys and Avalons being produced on the same production line at the same time. ---The Lean Lexicon

Standardization Heijunka Box
A tool used to level the mix and volume of production by distributing kanban within a facility at fixed intervals. Also called a leveling box. A load-leveling box has a column of kanban slots for each pitch interval, and a row of kanban slots for each product type. Just as we do not want to batch materials, we do not want to batch information. The Heijunka box is a method used to intercept the batches of information and organize them in a logical format. In this example, products A, B and C are produced at different intervals. ---Learning to See

Standardization Paced Withdrawal
The practice of releasing production instructions to work areas and withdrawing completed product from work areas at a fixed, frequent pace. In this type of handling system, a material handler, or waterstrider, performs a route through a facility at precisely determined time intervals. This is the cycle used to implement production mix and volume leveling. As the products are withdrawn from the shipping supermarket, the signal is given to production planning, which loads the Heijunka box. On a timed interval, a water strider takes the appropriate card (which is the production instruction) from the Heijunka box over to the assembly area, and then withdraws the previous time interval’s completed work and supplies to shipping supermarket. This cycle repeats itself throughout the shift based on the pitch time (interval). ---Learning to See

Courtesy of Duff-Norton, Charlotte, NC
Standardization Each cart represents one hour worth of production. The cart in the cell is the current hour’s production, while the cell waiting is the next hour’s production. Every hour, the water strider will deliver the next hour of production, and remove the previous hour of production. Everything is documented on the production control board on the left. Courtesy of Duff-Norton, Charlotte, NC

Standardization Supermarket
The location where a predetermined standard inventory is kept to supply downstream processes. Supermarkets are ordinarily located near the supplying process to help that process see customer usage and requirements. The Supermarket is basically a pull system for several products. ---Learning to See

Standardization Supermarket Pull System
This is an example of a pull system. As the packaging area withdraws product from behind the board, a card from the board is freed up. Each card on the board represents a position behind the board. When the card is freed up, it is sent to the upstream process signaling that some quantity has been consumed and must be replaced. Courtesy of Seamless Textiles, Humacao, PR

Standardization Kaizen
Continuous improvement of an entire value stream or an individual process to create more value with less waste. There are two levels of kaizen (Rother and Shook 1999, p.8): System or flow kaizen focusing on the overall value stream (kaizen for management). Process kaizen focusing on individual processes (kaizen for work teams and team leaders). Kaizen simply means continuous improvement. - Lean Lexicon

Summary - Standardization
Developing a Lean Factory Summary - Standardization Standardized Work Heijunka/Leveling Paced Withdrawal Supermarket Kaizen

Goals - highest quality, lowest cost, shortest lead times Just-In-Time continuous flow takt time/pace pull system triggers Involvement Jidoka separate man & machine work identify abnormal conditions poka yoke Heijunka Standardized Work Kaizen The employees are located in the center of the model, because Toyota considers their employees the lifeblood of the operation. They understand that in order for the system to work well, employee involvement must be very high. Stable Manufacturing Process

Involvement Workplace Practices Teams
with rotation of highly specified jobs. Cross trained and multi-skilled employees who can work many operations within a cell and even operations in different cells Continuous improvement philosophy Process quality, not inspection Use of participatory decision making Quality Control Circles, team-based problem solving, suggestion systems, etc.

Keys To Success Focus on the goal- eliminate waste!
Gather baseline information and measure results Get everyone involved Keep it simple _______________________________________________________________

Reference Materials Lean Thinking by Jim Womack and Daniel Jones
Lean Production Simplified by Pascal Dennis Learning to See, Mike Rother, John Shook, The Lean Enterprise Institute, Inc, 1998. “Decoding the DNA of the Toyota Production System” by Stephen Spear and H. Kent Bowen, Harvard Business Review, September-October 1999, pp

Lean Enterprise Advancement Program (LEAP) www.ies.ncsu.edu/lean

LEAN MANUFACTURING PRINCIPLES

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