Certified Six Sigma Black Belt Lean Enterprise Concepts Questions and Answers — Questions and Answers
Question 1: A team is analyzing a process that has long and unpredictable changeover times between product models, leading to excessive downtime and large batch sizes. Which of the following Lean tools is specifically designed to address this type of problem?
- 5S
- Single-Minute Exchange of Die (SMED) (Correct answer)
- Jidoka
- Heijunka
Correct answer: Single-Minute Exchange of Die (SMED)
Single-Minute Exchange of Die (SMED) is a system focused on dramatically reducing the time it takes to complete equipment changeovers. Its primary goal is to convert as many changeover steps as possible to 'external' (performed while the equipment is running) and to streamline the remaining 'internal' steps. This reduction in changeover time allows for smaller batch sizes, increased flexibility, and less downtime.
Question 2: A customer contact center operates for an 8-hour shift (480 minutes). During this shift, there is one 30-minute lunch and two 15-minute breaks. The daily customer demand is 210 calls. What is the Takt Time for this process?
- 2.29 minutes per call
- 1.90 minutes per call
- 2.00 minutes per call (Correct answer)
- 2.40 minutes per call
Correct answer: 2.00 minutes per call
Takt Time is calculated as Net Available Work Time divided by Customer Demand. First, calculate the Net Available Work Time: 480 minutes - 30 minutes (lunch) - 2 * 15 minutes (breaks) = 420 minutes. Then, divide by the customer demand: 420 minutes / 210 calls = 2.00 minutes per call. This means a call must be completed every 2 minutes to keep pace with customer demand.
Question 3: Which of the following BEST describes the primary purpose of Heijunka (production leveling)?
- To stop the production line automatically when a defect is detected.
- To organize the workplace for efficiency and effectiveness by eliminating clutter.
- To reduce batch sizes by enabling rapid equipment changeovers.
- To smooth the production of different product models over time to match the pace of customer demand. (Correct answer)
Correct answer: To smooth the production of different product models over time to match the pace of customer demand.
Heijunka, or production leveling, is a technique used to reduce unevenness (Mura) in the production process. Its primary goal is to produce goods at a constant rate, leveling the mix and volume of products over time to dampen the fluctuations of customer orders and create a more predictable and stable workflow.
Question 4: A manager notices that experienced machine operators are frequently assigned simple, repetitive tasks far below their skill level, while complex problem-solving is escalated to engineers who are often unavailable. This practice leads to delays and low morale among the operators. According to the 8 Wastes of Lean, which waste is most evident in this scenario?
- Motion
- Waiting
- Non-Utilized Talent (Correct answer)
- Defects
Correct answer: Non-Utilized Talent
This scenario is a classic example of Non-Utilized Talent (or underutilized skills), which is recognized as the 8th waste of Lean. It occurs when an organization fails to use the full knowledge, creativity, and skills of its workforce. Assigning highly skilled operators to menial tasks instead of empowering them to solve problems is a waste of human potential.
Question 5: The Lean principle of Jidoka, often translated as 'autonomation', is best described as:
- A visual scheduling system to manage and control the flow of work.
- A method for reducing equipment changeover times to under 10 minutes.
- Providing machines and operators the ability to detect an abnormal condition and immediately stop work. (Correct answer)
- A technique for leveling the production schedule in both volume and mix.
Correct answer: Providing machines and operators the ability to detect an abnormal condition and immediately stop work.
Jidoka, or 'autonomation' (automation with a human touch), is a core pillar of the Toyota Production System. It empowers either the machine or the operator to halt the production process as soon as an abnormality or defect is detected. This prevents the production of further defects and allows for immediate investigation into the root cause of the problem.
Question 6: After creating a detailed current-state value stream map, a Six Sigma team's primary objective in developing a future-state map is to:
- Document all non-value-added activities currently in the process.
- Calculate the precise Takt time for the current production rate.
- Design a streamlined flow that eliminates sources of waste and improves value delivery. (Correct answer)
- Create a training manual for new employees based on the current process.
Correct answer: Design a streamlined flow that eliminates sources of waste and improves value delivery.
While the current-state map identifies existing waste, the future-state map is a design tool. Its primary purpose is to envision and design a more efficient, waste-free process that operates on Lean principles like continuous flow, pull systems, and production leveling to deliver maximum value to the customer. It serves as the blueprint for the improvement efforts.
Certified Six Sigma Black Belt Lean Enterprise Concepts Questions and Answers
A team is analyzing a process that has long and unpredictable changeover times between product models, leading to excessive downtime and large batch sizes.
Which of the following Lean tools is specifically designed to address this type of problem?