ME503 Final Exam
A number of different motivations (or benefits that result) for applying SMED were discussed. Describe three (3) motivations/benefits of applying SMED. (at least one sentence each).
Capability to respond to customer requirements - Reducing changeover time shortens lead time, allowing more time to respond to changes in customer requirement. Eliminates setup errors - SMED perfects the process of changing production of parts, reducing the chance of mistakes/errors in setup. Improves quality and safety - SMED perfects the process of changeover which reduces the chance of mistakes resulting in injury or defects.
Effectiveness, feasibility and risk must be evaluated for each of the countermeasures selected to address the prioritized problem. Explain, in one statement each, why these three criteria are important.
Effectiveness evaluation will help figure out if the the countermeasure can actually solve the problem. Evaluating feasibility can answer questions regarding cost, time, etc. Evaluating risk can emphasize any other costs that come with the countermeasure.
In mixed model production, the daily quantity of each product needed are produced as small batches. (True or False)?
False
Standardized work deters creativity in team members. (True or False)?
False
The Takt time is the rate at which a production line can manufacture items. (True or False)?
False
The queue time for the triangle kanban is the only factor that determines the leadtime between releasing the triangle kanban and receiving inventory from the upstream station. (True or False)?
False
The ultimate goal of lean manufacturing is to develop production systems that are based on the 'pull' philosophy. (True or False)?
False
In the future-state, all stations downstream from the 'pace maker' process must follow one-piece flow. (True or False)?
True
Kanban lanes can be used to implement signal kanban systems. (True or False)?
True
Product variation must be constrained for kanban systems to work effectively. (True or False)?
True
Standardized work can serve as an improvement baseline. (True or False)?
True
The three basic elements of information that must be included in standardized work are: Takt time, work sequence and WIP levels. (True or False)?
True
When starting to implement a lean system with one-piece flow, starting with a 'build to supermarket' is the less risky strategy to follow. (True or False)?
True
With make-to-fill signal kanbans, the production batch size depends on difference between the current inventory level in supermarket and its capacity. (True or False)?
True
Describe what is meant by 'using parallel operations' in SMED to reduce changeover time by using an example that was used in the lecture video. (2-3 sentences).
Using parallel operations means to be working on different tasks at the same time. This is usually done by increasing the number of workers. For example, in the pit stop, there were workers assigned to replacing each wheel instead of one worker working on all of them.
A heijunka or load-leveling box is used to: a. Communicate requirements to supplier process b. Help with paced withdrawal of orders c. To communicate batch production schedule d. Release orders at the cycle time frequency
b. Help with paced withdrawal of orders
The first step in SMED is: a. Using intermediate jigs b. Separating internal and external setup c. Converting internal to external setup d. Standardizing for function not for shape
b. Separating internal and external setup
Which Statement does not reflect the view of standardized work in lean? a. Standardized work is the most efficient known way to manufacture a product. b. Standardized work is a way for management to impose production rates on a workforce. c. Standardized work in lean should be updated regularly. d. The employees on the line should be involved in establishing standardized work in lean.
b. Standardized work is a way for management to impose production rates on a workforce.
A load leveling box will generally have: a. A column for each pitch interval b. A column for each product and row for each pitch interval c. A column for each pitch and a row for each product d. A row for each product
c. A column for each pitch and a row for each product
Which of the following is not a sub-step for root cause analysis as described in the 8-step problem solving approach? a. Doing Genchi Genbutse b. Brainstorm for possible causes c. Ask who is responsible for the problem d. Identify the root cause
c. Ask who is responsible for the problem
Which of the following (information) is not essential to have on a kanban card? a. Part/product ID/name b. Conveyance/production quantity c. Cycle time/lead time for supplying part/product d. Supplier station and receiving station
c. Cycle time/lead time for supplying part/product
Which of the following statements is accurate about CONWIP? I. They are used to control the inventory between a set of stations. II. They follow a push strategy within the stations that are connected. III. CONWIP can help control inventory in situations when there is processing time variation between different products. a. I and II only b. II and III only c. I, II and III d. I and III only
c. I, II and III
Which of the following were observed in the case study described in the chapter from Gemba Walks? I. Supermarkets and kanban system was implemented and functional. II. There was a value stream manager responsible for all the steps in the process. III. Employees were not trained in the lean procedures. a. I only b. I and II only c. III only d. I and III only
c. III only
In a lean manufacturing system, orders are released to the pace maker process at a certain time interval. This is referred to as: a. Cycle time b. Takt time c. Pitch d. Lead time
c. Pitch
Which of the following is not a sub-step in 'Problem Breakdown'? a. Go to point of occurence b. Breakdown the vague problem c. Visualize the gap d. Identify prioritized problem
c. Visualize the gap
Which of the following is not a requirement to implement flow production? a. Small lot production b. Designing production system for fluctuations in demand c. Leveled production Correct! d. Large lot production
d. Large lot production
In the case study from Gemba Walks, shipping releases were communicated by physical kanbans. Which of the following is correct about the execution of the kanban system and shop floor status? a. Both customers sent kanbans in a consistent pattern that helped control WIP b. Both customers sent kanbans erratically, leading to large WIP in both shipping lanes c. Kanbans were used effectively and it allowed controlling WIP d. One customer sent kanbans erratically, leading to large WIP in that customer's shipping lanes
d. One customer sent kanbans erratically, leading to large WIP in that customer's shipping lanes
The 8 steps in the structured problem solving process can be categorized under the PDCA cycle. What does PDCA stand for? a. Plan, define, check, analyze b. Plan, design, check, act c. Plan, design, control, act d. Plan, do, check, act
d. Plan, do, check, act
These types of kanbans are used to provide authorization to the upstream workstation to start production. a. Conveyance Kanban b. Withdrawal Kanban c. Signal Kanban d. Production Kanban
d. Production Kanban
Which of the following is not correct about standardized work? a. It can help build quality and reduce cost. b. It can help avoid overproduction. c. Standardized work helps to identify opportunities for improvement.. d. Standardized work must be updated annually.
d. Standardized work must be updated annually.
Which of the following statements is not correct about 2-card kanban systems? a. They are used when distance between stations is high b. There will be multiple cards circulating c. There is additional delay in circulation when these types of kanbans are used d. The two kanbans used are withdrawal kanban and signal kanban
d. The two kanbans used are withdrawal kanban and signal kanban
When are signal kanbans used? a. When the part variety is high b. When the customer station has long setup time c. When the two stations are far apart d. When the setup time for the supplying station is large
d. When the setup time for the supplying station is large
Designing the manufacturing system to handle fluctuations in demand is important to enable one-piece flow. Explain how a production line can be designed and/or managed to cope with changes in demand? What can be done when demand increases and what can be done when demand decreases?
A production line can be designed to cope with changes in demand by making the work schedule as flexible as possible. For example, each work day could consist of 2 separate shifts with 4 hour breaks in between. When demand increases, time between shifts can be used to meet the demand. Another way to design a production line to cope with changes in demand is to implement one-piece flow. This way, products can be made accordingly to demand. (4.5/6)
A standardized work sheet developed by a team at Lexington Iron Works is shown below. Based on the principles discussed in the lectures, describe what additional information must be included here to make it a useful tool for continuous improvement. In your answer, you must identify at least 4 types/pieces of information that is not included and discuss what they are.
Additional information that must be added is symbols for safety points, quality checks, and WIP's such as + signs for safety, diamonds for quality checks, and dots for WIP's.. Another piece of information that must be added is arrows connecting each task, these will make comprehension of work flow easier. Takt time is another piece of information that is not included, takt time is the time between successive parts going out of a system. Finally, wait and walk times must be recorded as well. This represents the time used transporting or waiting on machines/other workers.
Standardized work is one of the most important tools used in a lean manufacturing environment. Five of the primary reasons for their usefulness/significance were discussed in the lecture. Describe three of these reasons (one sentence each).
I. Problem Identification II. Respect for Customers III. Improvement Baseline IV. Improvement Measurement V. Real Time Status Monitoring
What are two practices that can be used to convert internal setup steps to external setup? (2-3 sentences)
One practice that can be used is to construct check tables, which are extremely effective visual techniques. Another practice is to improve the transporting of dies, supplies and other parts.
We discussed that achieving one-piece flow between stations is not always feasible. Supermarkets and kanbans must be used in such situations. Describe two situations that would prevent one-piece flow between two stations and explain why they act as barriers ( no less than 2-3 sentences for each situation).
One situation is that the cycle times vary between stations. For example, if there is 2 work stations in a production line but the first workstation process takes twice as long as the second, work station 2 will have to wait for station 1 to complete. This causes wasted time from waiting which makes one piece flow unfeasible. Another situation would be if the workstations were not set up efficiently. For example, if the workstations are too far apart, there would be time wasted moving the parts from one station to another. This would disrupt the one-piece flow.
A 2x2 matrix-type figure was shared in week 8 to discuss the importance of developing a countermeasure that will solve the problem and establish a procedure that is repeatable. Explain (in 2-3 sentences) which of the 8-steps helps make that countermeasure part of the new procedure that will always be applied.
Step 6 of the structured problem solving process helps make the countermeasure part of the procedure. It is the first step that involves actually implementing the countermeasure into standardized work. Steps 7 and 8 work towards improving the countermeasure and standardizing it.
Changes in customer demand can necessitate changing the takt time. However, too frequent takt time changes can be costly as it will require changing all standardized work. How can you avoid takt time changes when product demand increases by a moderate amount? Use a simple numerical example to elaborate your answer.
Takt Time = Total Time Available / Total Customer Demand
Changes in customer demand can necessitate changing the takt time. However, too frequent takt time changes can be costly as it will require changing all standardized work. How can you avoid takt time changes when product demand increases by a moderate amount? Use a simple numerical example to elaborate your answer.
Takt time changes can be avoided by changing the total time available. If product demand increases, total time available must increase as well to keep takt time stable. THis could be done by extending the shift period, taking time out of breaks, or finding new ways to save time in the production process. Example: Current takt time is 60 seconds (420 minutes available / 420 units demanded). The demand increases to 450 units. To avoid takt time changes, you must add 30 minutes to the end of each
When a prioritized problem has been solved by developing and successfully implementing a countermeasure, the new procedure must be standardized and yokotened. What should be done next? Explain what should be done and the reasoning for your recommendation in 2-3 sentences.
The next step would be to start the next round of kaizen, or continuous improvement. This means searching for other problems or issues that need to be solved and repeating the 8-step structured problem solving process.
The goal of structured problem solving is to find a solution/countermeasure that provides which of the following? (a.) Acceptable results (b.) Repeatable procedure a. Both (a) and (b) above b. Only (a) above c. Neither (a) or (b) d. Only (b) above
a. Both (a) and (b) above
When implementing continuous flow, where should one start? a. From the process closest to the customer b. From the process that has the largest cycle time c. From the process that is most distant from customer d. From the process that has the largest changeover time
a. From the process closest to the customer
If stations are to be combined to implement one-piece flow in the future-state, which of the following must be achieved? I. Cycle time of all stations must be reduced to less than/equal to takt time II. Changeover time for all the stations linked must be zero. III. Uptime for all stations must be made 100%. IV. All stations must be dedicated to the product family being considered. a. I, II, III and IV b. II, III and IV only c. I and II only d. I, II and III only
a. I, II, III and IV
Which of the following wastes cannot be directly eliminated/avoided by implementing a pull production system? a. Overprocessing b. Excess Inventory c. Overproduction d. Unnecessary transportation
a. Overprocessing
The question 'Why?' is asked repeatedly (at least five times--hence called five why's analysis) is used at which step during problem solving? a. Root cause analysis b. Problem breakdown c. Countermeasure development d. Target setting
a. Root cause analysis
In a lean manufacturing system, when continuous flow cannot be implemented, one must use: a. Supermarkets and kanban b. Push production c. Batch production d. Manufacturing cells
a. Supermarkets and kanban
In SMED, which of the following statements is correct about 'internal setup'? a. These are changeover steps that must be performed when the machine is stopped. b. These are changeover steps that can be done when the machine is still running c. These are changeover steps which require approval by the Manager, before they can be changed. d. These are changeover steps that can be done by someone from the maintenance department
a. These are changeover steps that must be performed when the machine is stopped.
In pull production systems, one process/workstation is selected as the 'pace maker' process. Which of the following statements accurately reflects what a pace maker process is? a. This is the process to which the production schedule is released b. It is the process that determines the takt time for the production line c. This is the process that has the largest cycle time d. This is the process with the longest changeover time
a. This is the process to which the production schedule is released
Understanding the ultimate goal of your work is an important step in/for: a. Root cause analysis Correct! b. Clarifying the problem c. Developing countermeasures d. Standardizing successful procedures
b. Clarifying the problem
Which of the following is a limitation with fixed lot-size signal kanbans? a. Supplier station can produce a variable quantity, as needed downstream b. Customer station can run out of inventory due to delays in part delivery c. Customer station supermarket will always be re-filled to full capacity d. Inventory will be delivered at fixed time intervals
b. Customer station can run out of inventory due to delays in part delivery
Which of the following statements is not accurate about part-specific kanbans? a. They connect inventory between two stations b. Each part will have it's own kanban c. They are used to limit the inventory between a set of stations d. They are difficult to use when part variety is high
b. Each part will have it's own kanban