Deck 16: Lean Systems

Question 1

Waiting for parts to arrive or for machines to finish production is considered a form of waste under the principles of mass production.

Answer 1

False

Question 2

Contrast the application of lean concepts in North American-based facilities versus Japan-based facilities, and describe the benefits and drawbacks of lean production.

Answer 2

Lean North American plants are typically larger, deliveries from suppliers are less frequent, more buffer inventory is held, and kanbans are very simple compared to lean plants in Japan. The slow pace of continuous improvement is hard to maintain for North American workers. Thus, kaizen blitzes, intense process improvement over a week's time with immediate results, are easier and more energizing to conduct. Some benefits of lean production include reductions in manufacturing cycle time, reductions in inventory, reductions in labour costs, and reductions in space requirements. However, there are drawbacks. It can be difficult to maintain the discipline of lean production, and lean production may not be the best choice for high-volume repetitive items where mass production is more common. Also, lean production can present problems when unexpected changes in demand or supply occur.

Question 3

In lean production, waste is defined as anything that does not add value to the product.

Answer 3

True

Question 4

A kanban square is a marked area designated for holding a set quantity of output.

Question 5

Describe how lean systems can be applied in other situations, such as services, the supply chain, and environmental initiatives.

Question 6

General purpose machines are an example of flexible resources.

Question 7

The individual generally credited with the development of lean production is an American.

Question 8

Takt time is the pace at which production output is aligned with machine capacity.

Question 9

Push systems rely on predetermined production schedules often generated by computerized systems.

Question 10

Kanbans were derived from the two-bin inventory system.

Question 11

Kaizen is a Japanese term that means fool proofing to prevent defects.

Question 12

The concept of pull production is easy to implement because it is similar to traditional scheduling procedures.

Question 13

The number of kanbans needed to maintain control in a pull system can be calculated from demand and lead time information.

Question 14

Taiichi Ohno observed that customers in American supermarkets pull items through the system.

Question 15

Kanbans are used to maintain the discipline required of a push production system.

Question 16

Mass production means doing more with fewer workers, less inventory, and less space.

Question 17

Producing items before they are needed is considered waste under the principles of lean production.

Question 18

Manufacturing cells are comprised of similar machines to process a family of parts.

Question 19

The time required for a worker to complete one pass through the operations assigned to her is called the operator cycle time.

Question 20

Describe the 10 basic elements of lean production

Question 21

Internal setup activities can be performed when a process is running.

Question 22

Total productive maintenance combines preventive maintenance with kaizen.

Question 23

A poka-yoke is any foolproof device that prevents defects or injury from occurring.

Question 24

A push system prevents both overproduction and underproduction.

Question 25

In the dual kanban system, a withdrawal kanban authorizes the production of goods.

Question 26

Advantages of small-lot production include requiring less space and lower capital investment.

Question 27

The pull system was developed by Ohno to coordinate production between processes.

Question 28

The concept of cellular layouts was developed by a U.S. engineer in the 1920s.

Question 29

The output of a manufacturing cell is changed by adding or removing workers.

Question 30

Small-lot production reduces lead time but increases quality problems.

Question 31

Flexible resources are a basic element of lean production.

Question 32

In lean production, a strong relationship exists between setup times and small lots.

Question 33

One benefit of small-lot production is that workers show fewer tendencies to let poor quality pass.

Question 34

One component of lead time, setup time, is often the biggest bottle neck.

Question 35

Setup time is not a component of the cumulative lead time for a manufactured product.

Question 36

Reducing variability in production through more accurate demand forecasts is one way to maintain uniform production levels.

Question 37

Lean concepts cannot be applied to services because services are intangible.

Question 38

The lower inventory levels associated with small-lot production make processes more dependent on each other.

Question 39

The authority for a worker to stop the production line when quality problems are encountered is known as poka-yoke.

Question 40

The lower inventory levels resulting from small-lot production hides problems in the production process.

Question 41

A workstation's output is 200 bottles of wine per hour. It takes 45 minutes to receive a withdrawal kanban of corks from the previous workstation. The withdrawal kanban is attached to a container holding 30 corks. The process uses a safety factor of 20 percent. What is the number of withdrawal kanbans needed to support the bottling process?

A) 4
B) 5
C) 6
D) 3

Question 42

Poka-yoke is a Japanese term used to describe the removal of waste in a lean production system.

Question 43

Which of the following is not a basic element of lean production?

A) flexible resources
B) pull system
C) repetitive production
D) small lot production

Question 44

The pace at which production should take place to match the rate of customer demand is known as

A) product flow time.
B) jidoka time.
C) kanban time.
D) takt time.

Question 45

___ is generally credited with the development of lean production.

A) Frederick Taylor
B) W. Edwards Deming
C) Taiichi Ohno
D) none of the above

Question 46

A workstation must produce 400 units an hour. It takes 24 minutes to receive the necessary material for production from the previous workstation. Output is moved between workstations in containers holding 44 units. If the process uses a safety factor of 10%, then the number of kanbans that should be circulating between this workstation and the previous workstation is

A) 2
B) 4
C) 6
D) 8

Question 47

In a lean production system, kanban systems have been shown to handle large fluctuations in the production requirements on the final assembly line.

Question 48

Firms that adopt lean production experience reductions in cycle time, inventory cost, and employee training costs.

Question 49

To keep machines running, firms can use either breakdown maintenance or preventative maintenance.

Question 50

In a pull system reducing the number of kanbans

A) increases inventory making problems more visible.
B) reduces inventory making problems less visible.
C) reduces inventory making problems more visible.
D) increases inventory making problems less visible.

Question 51

All of the following factors pressure companies for quicker response and shorter cycle times except

A) demanding customers.
B) longer product life cycles.
C) globalization.
D) All the above are factors.

Question 52

A workstation's output is 200 bottles of wine per hour. It takes 30 minutes to receive a withdrawal kanban of corks from the previous workstation. The withdrawal kanban is attached to a container holding 30 corks. The process uses a safety factor of 20 percent. What is the number of withdrawal kanbans needed to support the bottling process?

A) 10
B) 2
C) 8
D) 4

Question 53

A workstation must produce 400 units an hour. It takes 24 minutes to receive the necessary material for production from the previous workstation. Output is moved between workstations in containers holding 44 units. If the process uses a safety factor of 10%, then the amount of safety stock on average would be

A) 16
B) 32
C) 8
D) 60

Question 54

In lean production, waste is defined as

A) overproduction.
B) high levels of inventory.
C) unnecessary movement.
D) All the above are waste.

Question 55

Early adopters of lean production in North America were unsuccessful because they tried to implement lean by slashing inventories and forcing their suppliers to make more frequent deliveries.

Question 56

In a pull production system, a card that corresponds to a standard quantity of production is known as a(n)

A) jidoka.
B) andon.
C) kanban.
D) kaizen.

Question 57

Mixed-modelling sequencing is used at Toyota to reduce setup times.

Question 58

Which of the following statements concerning small-lot production is not true?

A) Small-lot production requires less space.
B) Small-lot production requires more capital investment.
C) Small-lot production simplifies transportation between workstations.
D) Small-lot production allows processes to be moved closer together.

Question 59

Lower inventory levels make processes

A) less dependent on each other while keeping bottlenecks hidden.
B) less dependent on each other while revealing bottlenecks more quickly.
C) more dependent on each other while revealing bottlenecks more quickly.
D) more dependent on each other while keeping bottlenecks hidden.

Question 60

How many kanbans should circulate between two workstations if demand is 500 units per hour, lead time is 20 minutes, container sizes are 35, and the company uses a safety factor of 5%?

A) 4
B) 5
C) 12
D) 8

Question 61

All of the following are benefits expected from implementing lean production except

A) better quality.
B) shorter lead times.
C) reduced capacity.
D) improved sales.

Question 62

Which of the following is not a benefit of lean production?

A) greater flexibility
B) increased capacity
C) more customers
D) more product variety

Question 63

Procedures or mechanisms that make problems visible are examples of which of the following?

A) poke-yoke
B) kaizen
C) visual control
D) kanban

Question 64

Which of the following is not a typical component of lead time?

A) processing time
B) maintenance time
C) waiting time
D) setup time

Question 65

The benefits of lean production include all of the following except reduced

A) inventory.
B) product variety.
C) pace requirements.
D) lead times.

Question 66

Lean production is difficult to implement when

A) demand is highly variable.
B) product variety is high.
C) there are many unique products.
D) all of the above are true.

Question 67

The concept of allocating extra time to a schedule for planning, problem solving, and maintenance is known as

A) preventative scheduling.
B) preventive maintenance.
C) over capacity maintenance.
D) under capacity scheduling.

Question 68

A ___ kanban is used to order material in advance of production.

A) material
B) supplier
C) production
D) withdrawal

Question 69

Which of the following is not typically a component of lead time?

A) move time
B) breakdown time
C) wait time
D) setup time

Question 70

Mixed-model sequencing

A) facilitates total productive maintenance.
B) achieves uniform production levels.
C) increases product lead times.
D) reduces worker productivity.

Question 71

Improved scheduling of materials, workers, and machines will most generally affect

A) processing time.
B) move time.
C) waiting time.
D) setup time.

Question 72

___ setups that can be performed in advance while the machine is running.

A) Internal
B) External
C) Parallel
D) Unnecessary

Question 73

Which of the following is not considered a benefit of lean production?

A) less product variety
B) increased capacity
C) lower costs
D) greater flexibilty

Question 74

A ___ is a foolproof device that prevents defects from occurring.

A) kaizen
B) jidoka
C) muda
D) poka-yoke

Question 75

Which of the following is considered a benefit of lean production?

A) higher costs
B) strained relations with suppliers
C) better use of human resources
D) increased inventory

Question 76

Value stream mapping (VSM) is a tool for

A) reducing setup times.
B) improving quality at the source.
C) analyzing process flow.
D) designing manufacturing cells.

Question 77

The authority given to the worker to stop the production line if quality problems are encountered is known as

A) kaizen.
B) jidoka.
C) poka-yoke.
D) muda.

Question 78

Which of the following is not a principle for reducing setup times?

A) converting external setup to internal setup
B) converting internal setup to external setup
C) separating internal setup from external setup
D) performing setup activities in parallel

Question 79

Which of the following is not considered a benefit of lean production?

A) Reductions in manufacturing cycle time
B) reductions in inventory
C) reductions in labour costs
D) increases in automation

Question 80

Combining the practice of preventive maintenance with the concepts of total quality is known as

A) total preventive quality.
B) total productive maintenance.
C) quality breakdown maintenance.
D) reliability assurance.