Lean Manu Test 2
Types of Mass Production System
1. Assembly Line 2. Flow Line (Discrete and Continuous)
Production Systems
1. Job Shop Production System 2. Batch Production System 3. Mass Production System 4. Flexible or Cellular Manufacturing Systems
THE MOST FREQUENT COMPLAINT MADE
Why it is taking SO LONG? Many reasons - computer is slow, not enough workers, too many bags to check in etc. There must be a BETTER WAY to do this!
Lean Exercise Number Sorting
Why was it taking so long for you to find the answers? ❑ Because ❑ Because ❑ Because ❑ Because If you think you have waited long enough to see a doctor or dentist, check this out... The standard waiting time set for a patient to see a doctor in a veteran hospital is 22 days, but many patients waited more than 3 months to see their doctors.
Manufacturing Cell With Three Workers
Work more evenly spread out
Cellular and Flexible Manufacturing
• A system in which a large number of common parts are grouped together and produced in a cell consisting of all the machines that are needed to produce that group. • When large quantities of each part are required, cells can be made almost completely automated, leading to the designation of that cell as flexible manufacturing.
Largest Candidate Rule Feasibility
• A task is feasible only if it does not have any predecessors ( this is why task 1 is assigned first) or if all predecessors have been deleted • It may be assigned only if it does not exceed the cycle time for the station (i.e., the required cycle time aka takt time), and this condition can be checked by comparing the cumulative time of all the jobs so far assigned to that station, including the task under consideration, with the cycle time. • If no task is feasible, proceed to step 5. The largest of the cumulative times is the true cycle time.
Linked Workcells and Subcells
• A workcell usually has less than 10 stations, and usually each worker tends more than one station • Workcell output (capacity) can be varied by adding or removing workers • For complex products, multiple cells can be linked through kanbans (in Janpanese 看板 sign board or card) or other methods
Assembly Line Balance - Why Is It Important
• An assembly line consists of many individual workstations (manual, auto, semi-auto) in which one of the stations has the longest cycle time known as the bottleneck station. • Other workstations must be combined to have their cycle times as close to that of the bottleneck station to lower the unit cost of production - especially labor cost. • In doing so, the assembly sequences cannot be altered.
Cost Consideration
• Capital-intensive or labor-intensive production? • Careful analysis of real costs associated with automatic equipment must be done: • Cost of design • Cost of purchase-or-build • Cost of prove-in (installation & testing) • maintenance • Most automatic processes take longer than expected to produce quality and are expensive to modify if design changes are necessary.
Workcells are Flexible
• Flexible labour - multifunction, adaptable operators - the number of operators can be changed to change capacity • Flexible equipment - a variety of products are produced on the same equipment - this requires multifunctional machines • Achievable with basic technology!
Cellular Manufacturing
• Group dissimilar machines in manufacturing cell to produce family of parts • Workflows in one direction through cell • U-shaped for easy access and movement • One worker tends several machines • Cycle time adjusted by changing number of workers
Disadvantages of Job Shop Production System
• High costs for tooling and fixtures. • Difficult to achieve machine-load balancing • Excessive material handling • Large areas required to store work-in-process inventory. • Excessive bookkeeping for production shop orders. • Low productivity due to excessive setup time and material movement.
Advantages of Job Shop Production System
• High degree of flexibility to produce a variety of different products. • Quick response to changes in the market. • 30%-50% of the manufacturing systems in the US are of the job shop type.
Manufacturing vs Service
❑ Manufacturing organizations transform raw materials into components or finished goods. ❑ "Service" encompasses both service organizations (healthcare, banking, government, retail) and the service infrastructure in manufacturing organizations (marketing, sales, accounting, hiring, production control, engineering, R&D, and so on). ❑ Empirical data have shown that the cost of services are inflated by 30-80% waste - that is, the processes are filled with activities that add no value from the perspective of the customer.
Largest Candidate Rule
1. List the tasks in decreasing order of magnitude of task times, the task requiring the largest time being first. * Takt time should be known before you start balancing the assemble line 2. Designate the first station in step 1 as station 1 and number the remaining stations consecutively. Station 1 Tasks ? Station 2 Tasks? Station 3 Tasks? Station x The objective is to determine what task(s) to be assigned to each station. 3. Beginning at the top of the task list, assign a feasible task to the station under consideration. Once the task is assigned, all reference to it is removed from the predecessor task. * Task 1 should always be assigned to Station 1 (b/c it has no precessor) 4. Delete the task that is assigned from the first column of the task list. If the list is empty (which means all tasks have been assigned), go on to step 6; otherwise return to step 3. 5. Create a new station by increasing the station count by one. Return to step 3. 6. All jobs are assigned and the present station number reflects the number of station required.
Mass Production Types
1. Quantity production - Equipment is dedicated to the manufacture of one product - Standard machines tooled for high production (e.g., stamping presses, molding machines) - Typical layout - process layout 2. Flow line production - Multiple workstations arranged in sequence - Product requires multiple processing or assembly steps - Product layout (aka line or cellular layout) most common
Process Metrics
1. Time: process time and preproduction lead time 2. Changeover time 3. Typical batch sizes or practices 4. Demand rate 5. Percent complete and accurate (rwt information received) 6. Reliability (up time of machine or station) 7. Number of people 8. Inventory 9. Information technology used 10. Available time (business hours)
How/When Was Lean Developed?
1850 with Eli Whitney - Interchangeable Parts American Civil War starts - Drawing Conventions, Tolerances, Modern Machine Tool Development 1900s - Frederick Taylor (Standardize Work, Time Study, Work Standards, Worker/Management Dichotomy), Frank Gilbreth (Process Charts, Motion Study) Great War - Henry Ford (Assembly Lines, Flow Lines, Manufacturing Strategy) WWII - Edwards Deming, Juran - SPC, TQM 1950-80 - Eiji Toyota, Taichi Ono (Toyota Production System, Just-In-Time, Stockless Production, World Class Manufacturing) 1990s - Lean Manufacturing 2010 - Lean Production of Apple iPhones, iPads, Foxconn
Cellular Layout
5 workers - shorter cycle time Work flow with machines Workers at each or can move 2 workers - longer cycle time Worker at two machines and worker at three
Labor Assignment at Toyota: Jan.
8 workers were assigned in January Cycle Time: 1 min. per unit 6 workers were assigned in February Cycle Time: 1.2 min. per unit
Examples of Machine Coupling Alternative A
A flexible mfg. cell includes one Machine A and two Machine B. The individual cycle time: the sum of loading (including unloading) and processing time is given below. Machine A B Loading 2 5 Processing 8 7 Cycle Time 10 12 Note that "loading time" includes "time to feed a part into machine and remove it from the machine once done. Operator Idle Times One operator per machine (The rich man method) Output <- (10 min. per part) A [Operator 1: L:2 W:8 min] Idle time: 0 min Output <- (12 min. per part) B [Operator 2: L:5 W:7 min] Idle time: 0 min Output <- (12 min. per part) B [Operator 3: L:5 W:7 min] Idle time: 0 min Machine Idle Times The same The total cost = machine idle cost + operator cost = $0 + 3($6) = $18/hour
Q: What could be done if the Takt time is smaller than the task which has the shortest task time? For example: what if 0.75 (takt time) > 0.80 (Task 10).
A: You can reduce the cycle time of the bottleneck station by creating a parallel station. This way the cycle time can be cut in half.
Why Flexible Manufacturing
Advantages of Mass Production • It lowers the unit cost of production composed of: 1. Fixed cost (for set up) 2. Variable cost (for material and labor) • When the required quantity for each item does not warrant the use of a mass production system, flexible manufacturing would be a better choice.
Typical Process Cycle Efficiency (PCE)
Application - Typical Cycle Efficiency - World-Class Cycle Efficiency Continuous Manufacturing - 5% - 30% Business Processes (Service) - 10% - 50% Business Process (Creative/Cognitive) - 5% - 25%
Q: How fast can Boeing make a 737 airplane at its facility in Renton, Washington?
Assembly line speed: 0.2 ft. per minute Production Capacity: 31 aircrafts per month in 2005 (2 lines) 38 aircrafts per month in 2014 42 aircrafts per month in 2015 52 aircrafts per month in 2018 57 aircrafts per month in Mar. 2019 down to 42 per month now due to grounding of 737 Max
Why are Chinese leaner than Americans?
By using chopsticks, Chinese eat much slower than Americans.
A waitress is busy with refilling bread stick baskets at customers' tables at Olive Garden. Is this a value-added activity?
Customer welling to pay? No Business Requirement? No Non-Value Added
Define Value Flow Chart
Customer willing to pay? -> No -> Business requirement? -> No -> Non-Value Added Customer willing to pay? -> No -> Business requirement? -> Yes -> Business Non-Value Added Customer willing to pay? -> Yes -> Transform good or service? -> No -> Business requirement? -> No -> Non-Value Added Customer willing to pay? -> Yes -> Transform good or service? -> No -> Business requirement? -> Yes -> Business Non-Value Added Customer willing to pay? -> Yes -> Transform good or service? -> Yes -> Yes -> Done for the first time? -> No - > Business requirement? -> No -> Non-Value Added Customer willing to pay? -> Yes -> Transform good or service? -> Yes -> Yes -> Done for the first time? -> No - > Business requirement? -> Yes -> Business Non-Value Added Customer willing to pay? -> Yes -> Transform good or service? -> Yes -> Yes -> Done for the first time? -> Yes -> Value Added
What Is Lean?
Definition: ❑ Lean Manufacturing is a system of tools that enables an organization to eliminate all forms of waste from their systems. ❑ Waste is the use of any equipment, parts, material, space, or server's time that is not absolutely essential to adding value to a product or service. ❑ "If it doesn't add value, it's WASTE." "All we are doing is looking at a time line from the moment the customer gives us an order to the point when we collect the cash. And we are reducing that time line by removing the non-value added wastes" - Taiichi Ohno Ex: 1950 vs 2013 Pit Crew Comparisons Lean - the relentless pursuit of the perfect process through waste elimination". Driving improved customer satistfaction • Reduced cycles • Better delivery • More capacity • Better quality • Higher productivity
Process Layout
Different workstations (machines) with workers. Machines of same type are grouped together. Positioned for logical flow.
Product Layout
Discrete flow line Work flow one way. Work units travel that way. Workers in stations.
Assembly Line Efficiency
Efficiency (e) = 1-P P = Sum of Idle Times ((No. of Stations x True Cycle Time) - (Sum of Task Times)) / (No. of Stations x True Cycle Times)
How can an award-winning chef create perfect dishes without even tasting any of them?
Every dish tastes good! Customers should be pleased.
How LEAN is this system?
We need a metric to measure the leanness of a system.
Is inspection necessary or wasteful?
For example, an item is inspected 3 times before it is delivered to the customer to make sure it is not defective. ❑ Most likely wasteful. ❑ Customers do not care how many times the item have been inspected. ❑ Also, Inspection adds non-value-added time to the process. ❑ Eliminate inspection by improving the process so that no defective product or service can be generated. (6 Sigma) ❑ Redesign the product or service so that it can be produced with no errors. (Poka Yoke)
Little's Law
Lead Time = Amount of WIP/Average/Average Completion Rate WIP = Things In Process (TIP) ❑ Any work that is officially in the process and isn't yet complete. ❑ Those "things" can be customer requests, checks waiting to be processed, phone calls you have to return, reports you need to complete, etc.
A server is busy with fixing a side salad declined by the customer because ONE tomato is missing.
Is fixing a side salad a value-added activity? The McDonald's Side Salad should come with TWO TOMATOES. Note: McDonald' removed side salad from its menu in 2018. McDonald's Side Salad might come with more than TWO TOMATOES Defects (wrong dressings) Wasted ketchup Customer willing to pay? -> Yes -> Transform good or service? -> Yes -> Done for the first time? -> No -> Business requirement? -> No -> Non-Value Added
Relationships between Plant Layout and Type of Production Facility
Job shop: Fixed position layout High product variety Low production quantity Process layout Batch Production/Cellular Manufacturing: Process layout Cellular layout Average product variety Average production quantity Mass Production; consists of quantity and flow line Process layout Product layout Low product variety High production quantity
Closed-Loop Conveyor System
Loop of workflow Inputs and outputs go in and out of workflow. Workers up to loop.
Have You Had Your Big Breakfast for Dinner yet?
MSN News: McDonald's franchisees say all-day breakfast is a nightmare. (10-15-15) ❑The new menu is slowing down service, reducing average ticket costs, and causing chaos in the kitchens, franchisees said in a survey ❑Nearly a dozen more franchisees complained that it slowed down service and added complexity to the kitchens. ❑"Customers are abandoning us in droves because we are either too slow, or sub-par quality," one franchisee wrote.
Examples of Machine Coupling Alternative C
Machine A B Loading 2 5 Processing 8 7 Cycle Time 10 12 ▪ One operator attends Machine A ▪ One operator attends 2 Machine B Operator Idle Times Output <- (10 min. per part) A [Operator 1: W:2 I:8 min] Output <- (12 min. per part) B Output <- (12 min. per part) B [Operator 2: M+W:11 I:1 min] Idle time: 1 min - W(5)-M(0.5)-W(5)-M(0.5)-I(1) Machine Idle Times Output <- (10 min. per part) A [W:2 I:8 min] Output <- (12 min. per part) B [L:5 W:7 min] L(5)-W(7) Output <- (12 min. per part) B [L:5 W:7 min] The total cost = idle costs of machines + cost of operators = $0 + 2($6) = $12/hour
Examples of Machine Coupling Alternative B
Machine A B Loading 2 5 Processing 8 7 Cycle Time 10 12 ▪ One operator attends Machine A and Machine B. ▪ One operator attends Machine B ▪ Walking time = 0.5 min between machines * M/C B has a longer cycle time so it has to be started first. Operator Idle Times Output <- (12 min. per part) A Output <- (12 min. per part) B [Operator 1: M+W:8 I:4 min] Idle time: 4 min [Cycle: W(5)-M(0.5)-W(2)-M(0.5)-I(4)] Output <- (12 min. per part) B [Operator 3: W:5 I:7 min] Idle time: 0 min because the operator has not returned when M/C A stopped Machine Idle Times Output <- (12 min. per part) A [I:2 W:10min] Idle time = 2 min - L(2)-W(8)-I(2) Idle because the operator has not returned when M/C A stopped Output <- (12 min. per part) B [L:5 W:7 min] L(5)-W(7) Idle time: 0 min Output <- (12 min. per part) B [L:5 W:7 min] Idle time: 0 min Note that it takes 0.5 minute to work from one machine to the other. The total cost = machine idle cost + operator cost = idle cost of machine A + cost of operators = (2/12)$12 + 2($6) = $14/hour
Examples of Machine Coupling Alternative D
Machine A B Loading 2 5 Processing 8 7 Cycle Time 10 12 ▪ One operator attends all three machines Operator Idle Times Output <- (13.5 min. per part) A Output <- (13.5 min. per part) B Output <- (13.5 min. per part) B [Operator 2: M:13.5 min] W(5)-M(0.5)-W(5)-M(0.5)-W(2)-M(0.5) Machine Idle Times Output <- (13.5 min. per part) A [L:2 W:8 I:3.5 min] L(2)-W(8)-I(3.5) Output <- (13.5 min. per part) B [L:2 W:8 I:3.5 min] L(2)-W(8)-I(3.5) Output <- (13.5 min. per part) B [L:2 W:8 I:3.5 min] L(2)-W(8)-I(3.5) The total cost = idle costs of machines + cost of operator = (3.5/13.5) x $12 + [(1.5+1.5)/13.5] x $18 + $6 = $13.11
VSM Exercise
Plot: During peak hours, customers there are about 20 walk-in orders of sandwich meals (with side salad and soft drink) per hour in one of McDonald's restaurants in R city. The following data have been observed: ❑ Average waiting time to place order: 2 min. ❑ Average order taking time: 0.5 min. ❑ Average waiting time for the order to be processed:2 min. ❑ Average sandwich preparation time: 1 min. ❑ Average waiting time before the meal is given to the server: 2 min. ❑ Average process time for the server to give the meal to customer:0.5 min. Questions: On the average, ❑ What is total process time? ❑ What is total lead time (waiting time)? ❑ What is order-to-deliver time? ❑ How can the lead times be reduced? ❑ Where are the bottlenecks? ❑ If no additional workers can be hired, what are the areas that have the most improvement potential?
Process Cycle Efficiency (PCE)
Process Cycle Efficiency (PCE) relates the amount of value-add time to the total lead time of the process. PCE = Value-add Time/Total Lead Time Lead time is waiting and delay time + process time. (Note that some books define Lead time as waiting and delay time.)
VSM Strategy
Product or Service - What are Mapping? Current State Map - Understand how the existing process operates & identify the leverage points for improvement. Future State Map - Visualize what process could look like 3-6 months into the future- utilizing the resources already in place. Plan and Implementation - A plan to get there; what, when and how.
Layout for Job Shop and Batch Production Systems
Similar to process layout. Machines of same type are grouped together. Not positioned for logical flow.
VSM Steps
Step 1. Document Customer Information and Need. (See next slide) Step 2. Indentify Main Processes (in order) Process boxes are used for this purpose. Step 3. Selecting Process Metrics. (See next slide) Step 4. Perform Value Stream Walk-Through (Gemba Walk) Step 5. Establish How Each Process Prioritizes Work (for office tasks) ▪ Jobs are prioritized by the production schedule in a factory. Office tasks are often not prioritized. ▪ $ Value - high priced order gets first priority ▪ processing time ▪ size of job ▪ due date Step 6. Calculate System Summary Metrics Step 7. Design a future state by eliminating wastes in the current state. Step 8. Repeat Steps 1 through 7.
Number of Machine Needed
Steps: (1) Determine items to process per day for Operation i Ni = (Units required per day) / (1- defective rate) (2) Determine process time for Operation i Ti = Time per operation (1+personal allowance) (3) Determine total time for Operations i: TOi = Ni x Ti + set up time (4) Calculate total time required for all operations: TO = ∑ TOi (5) Determine number of machines needed: N = TO / (Shift time x plant efficiency)
Who Is Taiichi Ohno?
Taiichi Ohno was Assembly Manager for Toyota. In the 1950s, he made a series of trips to the United States and observed three events which allowed him to began to formulate what is now called the Toyota Production System. (1) rapid changeovers at Indy 500 (watch video) (2) flow assembly line at Ford's River Rouge plant (3) pull concepts used in US supermarkets
Total Cost for for Machine Coupling
The total cost consists of two components: (1) Machine cost (including idle cost) (2) Operator cost Why Idle cost? • When machines are in use, they are performing desirable, productive activities. • When they are idle, they are nonproductive and should be considered an expense. Note: The idle cost for machine may not be easily defined. Nevertheless, it can be set high if the goal is to increase the utilization rate of the machine. The total cost = machine idle cost + operator cost = $0 + 3($6) = $18/hour
Why are 1/3 of Chinese kids overweight?
They have dinned too often at fast food places like McDonald's and Burger King.
Extension of Variations on Stage Analysis
This analysis determines the cost of a good unit for different production yield structures: (1)Straight Line Model (2)Back Stream Model (Recycle Model) (3)Forward Stream Mode
Define Value
Three ways to categorize value: 1. Value-added activity Essential activities are called value added activities. 2. Waste, or muda (non-value-added activity) 3. Business non-value-added activities. These tasks must be completed due to regulatory, business or legal requirements, even if they are not traditionally defined as Value add. (e.g., President Trump's signature on a bill passed by Congress.)
Assembly Line Balancing Algorithms
Two most popular algorithms: 1. Largest Candidate Rule 2. Ranked Positional Weight Choose one with highest efficiency
Gemba/Walk
Used to describe personal observation of work - where the work is happening. Gemba menas "real things" in Japanese.
Problem with Using Line Yield to Estimate Input Units Needed
Using line yield to estimate N often results in underestimating the actual input required.
Who Defines Value?
Value is always defined by the customer.
Lean Example
Vanderbilt University Post Office, No more waiting in line to pick up packages
A VSM shows the Process Flow
Wait Time = 4.34 days Processing Time = 0.98 days Total Time = 5.32 days Nonvalue points = Sync report, kits, layout Our system = Push System Fund 10 days inventory Pay for 15-100 days Competitor = Pull System Fund 1 day
Shigeo Shingo
Worked as a railroad engineer in Taiwan during World War II. ❑ Taught industrial engineering methods at Toyota from 1955 to 1980. ❑ Received an honorary Doctorate of Management from Utah State University in 1988 for writings and teachings that made key contributions to the development of the Toyota Production System, the model for what would later be called lean management.
Manufacturing Cell With One Worker
Worker follows the flow of the product from machine to machine
Fixed-Position Layout
Workers around a product. Mobile equipment comes to workers. In 2011, one VP of Boeing said: 90% of Boeing Commercial Airplane Assembly Operations were non-valued added! ▪Plenty of opportunities for IEs to improve these operations -aircraft and ship building - Boeing, Lockheed Martin, Ingulls Ship Building Co
What would happen if the idle cost of machine is very high, say several times higher than the operator cost?
You have to find way to keep machine running most of time. In some cases, you might have to assign one operator to each machine so that there would be little machine idle time.
Six Sigma
focuses on ❑reduction of defects ❑elimination of variation
Mass Production System
• High-volume production • The entire plant is dedicated to manufacturing a single product. • Use very specialized equipment of super high speed. • Investment in special tools, jigs, and fixtures is large. • The work content is broken down into many small groups. • High efficiency is obtained by perfecting the tooling and method of work in each group. • Requires low-skilled workers (for product layout) (This is why many jobs have gone to China and other developing countries.) • High automation is achieved. (This is why jobs remain and are created in US.)
Ranked Positional Weight
• Instead of ranking the task in decreasing magnitude of time requirement, the RPW method ranks tasks according to their importance to the completion of all tasks. • The importance is measured by the ranked positional weight (RPW) of each element, which is the sum of the times for all elements that directly follow it in the precedence diagram plus the time for itself.
Batch Production System
• It is suitable for a firm that has numerous items to produce but not so large a variety. • The products to be made throughout the year are known, each having a stable and continuous demand. • It uses specialized equipment of high speed. • It requires medium skilled workers. • Different machines may be grouped together to perform certain tasks. • Productivity is higher than that of a job shop system.
Assembly Line
• It produces discrete products. • Partial assemblies are moved from one workstation to the next by conveyor belts. • The total work for a job is distributed among the workstations that form the assembly line such that all stations complete their assigned tasks in approximately the same time, called the cycle time. • Automobile manufacturing is a prime example.
Job Shop Production System
• It produces many different types of products with small production volume for each. • It uses a variety of general-purpose equipment and general-purpose tooling and fixtures. • It requires highly skilled workers • Similar machines can be grouped together within the plant to form a department. • The product moves from one department to another on the basis of its operational sequence.
Flow Line (continuous)
• It refers to a continuous production process such as that of chemical, liquids, gaseous products, and paper etc.
Machine Coupling
• Machine coupling is only possible only if the machine, when it is working, is capable of performing its task without any assistance from the operator. • In machine coupling a single operator is made responsible for operating a group of machines. • The use of worker-machine charts plays an important part in this development. • The chart graphically displays on the same scale the time when a person is working or idle.
Available Capacity
• Machines can seldom be used at full capacity throughout the production period. • Possible reasons: • Set up time loss • Time loss for preventive maintenance • Time loss for tool sharpening • Time loss for unpredicted failures and repairs • Time loss for operator-related factors: absence, personal time, bookkeeping, machine adjustments, and material preparations. That is why "plant efficiency" is < 100%.
Available Capacity - Allowances
• The loss of useful time is accounted for by many different allowances: • Set up time is measured or estimated for each type of operation and is incorporated into the time necessary to produce the units (unless it is very short or becomes negligible b/c of large production volume). • Personal allowance (5% to 15%), depending on the physical strength and dexterity required to perform the job, is given to the operator to accommodate his/her personal needs. This gives an operator "extra time" to complete his job.
Production Arrangement
• When planning to set up a new production facility, the final layout of the plant is unknown at this point. (This applies to facility expansions.) • The anticipated production arrangement should be decided upon: mass production, batch production, or job shop production.
What is Takt Time?
▪ Takt time = Available Work Time /Demand For example: To produce 400 parts in 400 minutes @ 100% efficiency (which is impossible). Takt time = 400 / 400 = 1.0 min. per part This calculation tells you how fast the bottle neck station's cycle time should be.
What Is a Value Stream?
❑ A Value Stream shows all activities (process) required to fulfill a customer request from order to delivery
Time Value Map
❑ A time-value map tracks any work item as it flows through the process and classify the time into one of three categories: a. value-added work b. waste that is required for business reasons c. non-value-added work (delays, wait, transportation, inspection etc.)
Construction of Time Value Map
❑ Follow the item through its process from beginning to end. ❑ Draw a timeline and mark off the time segments for each of these categories.
What Did the Lean Expert Say about Olive Garden Breadsticks?
❑ In late 2014, Darden's board was taken by activist investment fund Starboard Value, which had criticized the company's management of the chain. ❑ Among the complaints were that Olive Garden wasn't selling enough alcohol, particularly for an Italian chain, and that servers were wastefully handing out more breadsticks than necessary.
Why VSM?
❑ It helps you visualize more than just the single process level such as assembly, welding etc. ❑ Mapping helps you see the source of waste in your value stream. ❑ It ties together lean concepts and techniques. ❑ Value stream maps are used as a blueprint for the lean implementation. ❑ It shows the linkage between the information flow and material flow.
Why VSM? 2
❑ It produces a tally of non -value-added steps, lead time, distance traveled, the amount of inventory etc. ❑ It follows the process from beginning to the end, and draws a visual representation of ✓ Primary transformation steps ✓ Information flows ✓ Process flows/delays ✓ Key time metrics: process time and lead time.
Lean vs TPS
❑ Most of Lean concepts were developed based on TPS. ❑ The term Lean manufacturing was first coined by John Krafcik in his 1988 article, "Triumph of the Lean Production System." ❑ He was the first American engineer hired by the GM and Toyota joint-venture partnership NUMMI, and later became an industry expert on lean production while at MIT. ❑ He was the CEO of Hyundai from Nov. 2008 - Dec. 2014 and had worked for Ford Motor Company for 14 years as its Chief Engineer. ❑ He is now Self-Driving Car Chief Executive, Alphabet Inc.
Distributions of Activities
❑ Most processes are 3%-5% value added, and maybe 10% to 15% business non-value added. ❑ But most processes are non-value added. (85%)
Toyota Production System
❑ One piece flow (One unit flow) - Flow ❑ Just in time manufacturing and ordering (Kanban System) - Pull ❑ Zero inventory - Pull ❑ Production line balancing - Flow ❑ Production schedule stabilization - Flow ❑ Zero Defect - Pull ❑ Quick changeover ❑ Multifunctional Workers ❑ Worker participation in continuous improvement (Kaizen)
Lean Six Sigma
❑ Organizations implementing Lean or Six Sigma alone would see their profits grow. ❑ However, integrating Lean and Six Sigma would maximize the profit of an organization.
Why Service Are Full of Waste
❑ People in manufacturing have the ability to physically see and trace the flow of work and see the work-in-process (WIP). ❑ In services, work is largely invisible. It is hard to see visible WIP or things-in-process (TIP) unless they are paper stacks or customers waiting in line. ❑ TIP like E-mails , electronic reports, voice messages etc. are hard to see and count.
Process Cycle Efficiency (PCE) Details
❑ Process Cycle Efficiency allows you to quantify the opportunity. ❑ Typical process cycle efficiencies in services run at about 5%, meaning that work spends 95% of its "in process" time just waiting. ❑ A PCE of less than 10% indicates that the process has a lot of non-value-add waste opportunity. ❑ A Lean process is one in which the value-add time is more than 20% of the total lead time of that process.
Bruce Lee Master of Lean
❑ See what Bruce Lee said when he auditioned for the role of Kato in The Green Hornet. ❑ Noted that this footage is colorized by Artificial Intelligence. No body fat and eliminated waste Practiced one fluid motion of attack Accomplishes high effectiveness with minimal resources (effort) Every move is utilized to reach goal No non-value moves
Challenge
❑ Sometimes it is difficult to distinguish waste from a necessary operation. ❑ Many business transactions are invisible (e-mails, text messages, phone messages etc.)
Five Principles of Lean
❑ Specify Value ❑ Eliminate Waste ("Muda" in Japanese) ❑ Flow the Product ❑ Pull Demand ❑ Pursue Perfection
Value Stream Mapping
❑ VSM is drawn at a level higher than the process chart. ❑ The objective is to identify waste and try to find ways to eliminate it.
What is Value Stream Mapping?
❑ Value stream mapping (VSM) is a process of examining the entire chain of events that must happen from the time an order for a product is received until it is delivered. ❑ VSM maps the process as it presently exists, and suggests, via examination, improvements that are needed. ❑ It displays material flow, product flow, and information flow. ❑ The mapping starts from when the order for the product is received and ends when the product is delivered to the customer. ❑ Ideally, all in-between stages that a product or a partial product must pass through must add value to the product and any non-value-added activities should be eliminated.
Lean
❑focuses on process velocity. ❑provides tools for analyzing process flow and delay times at each activity in a process. ❑centers on the separation of "value-added" from "non-value-added" work (waste) with tools to eliminate the root causes of non-value-added activities and their cost ❑Provides a means for quantifying and eliminating the cost of complexity.
