CPM CPM Lean Manufacturing & Waste Reduction 2 — Questions and Answers
Question 1: What does Overall Equipment Effectiveness (OEE) measure in a lean plant?
- Total cost of equipment ownership
- Combined impact of availability, performance, and quality losses (Correct answer)
- Number of preventive maintenance work orders completed
- Machine operator utilization rate
Correct answer: Combined impact of availability, performance, and quality losses
OEE = Availability × Performance × Quality, providing a single metric that captures all major equipment loss categories.
Question 2: In lean manufacturing, a 'supermarket' refers to:
- A dedicated break room for plant employees
- A controlled inventory location that replenishes downstream processes via pull signals (Correct answer)
- The purchasing department's supplier catalog system
- A visual board displaying daily production targets
Correct answer: A controlled inventory location that replenishes downstream processes via pull signals
A lean supermarket is a strategically located inventory buffer that is replenished by upstream processes only when downstream processes withdraw items.
Question 3: Which of the following best describes 'heijunka' in a lean production system?
- Mistake-proofing devices that prevent defects
- Production leveling that smooths volume and mix over time (Correct answer)
- Continuous flow through elimination of all buffers
- Visual signals that authorize production or movement
Correct answer: Production leveling that smooths volume and mix over time
Heijunka levels production by distributing orders evenly over a shift or day to reduce variability and prevent overburden (muri).
Question 4: A plant manager wants to identify non-value-added activities in a process. Which lean waste category covers unnecessary movement of workers within a workstation?
- Transportation
- Motion (Correct answer)
- Waiting
- Inventory
Correct answer: Motion
Motion waste refers to unnecessary physical movement by operators (bending, reaching, walking) within their work area, distinct from transportation of materials.
Question 5: When implementing a pull system, what is the function of a kanban card?
- Record daily production output for management reporting
- Authorize the production or movement of a specific quantity of material (Correct answer)
- Track employee attendance and hours worked
- Document machine maintenance schedules
Correct answer: Authorize the production or movement of a specific quantity of material
A kanban card is a visual signal that authorizes upstream processes to produce or supply a defined quantity only when downstream consumption creates a need.
Question 6: The 'seven flows' concept in lean manufacturing includes the flow of raw materials, WIP, finished goods, operators, machines, information, and:
- Capital expenditures
- Engineering change orders
- Energy (Correct answer)
- Suppliers
Correct answer: Energy
Energy is the seventh flow in lean manufacturing, and optimizing all seven flows is essential to building a truly waste-free value stream.
CPM CPM Lean Manufacturing & Waste Reduction 2
What does Overall Equipment Effectiveness (OEE) measure in a lean plant?