Lean Manufacturing Flashcards
Lean Thinking - The 5 principles
- Value:
- Specify value from the standpoint of the end customer.
- Value Stream:
- Identify the value stream for each product.
- Flow:
- Make value flow without interruptions.
- Pull:
- Let the customer pull value from the next upstream activity.
- Perfection:
- Pursue perfection.
LEAN & WASTE
- The definition of Lean: The identification and elimination of waste.
- The definition of Waste: Any part of the process that adds no value.
Value Stream
- Raw Material > Stamping > Welding > Assembly Cell > Finished Product
- All steps, value added & non-value added, required to bring the product from raw material to customer.
Value Stream Mapping - VSM
- Follow a product’s production path from beginning to end, and draw a visual representation of every process in the material & information flow.
- Allows to see and understand the flow of material and information as a product makes i’s way through the value stream.
VSM - Advantages
- Helps to visualise flow
- Allows to see & identify the sources of waste easier
- Shows the links of information and material flow.
- Provides a common language for talking about manufacturing processes
- Allows to describe in detail how the plant should operate in order to create flow.
- Forms the basis of an implementation plan (blueprint for lean implementation).
Using the Value Stream Mapping Tool
-Current State Drawing:
*Understand how the shop floor currently operates operates!
*Map material & information flow
*Draw using icons
*Start with “door to door” flow.
*Walk the floor & get actuals:
.No standard times
.Draw by hand and in pencil.
-Current State - foundation for the future state.
Value Stream Manager
- For product ownership beyond functions.
* Value Stream Managers should make their progress reports to the top manager on site
Levels of a Value Stream
Process Level > Single Plant > Multiple Plants> Across Companies
ACME Stamping Data Set
ACME Stamping Company produces several components for vehicle assembly plants. This case concerns one product family; a steel instrument panel bracket sub assembly in two types: one each for LH & RH drive versions of the same model. The components are sent to State Street Assembly Plant (the customer).
ACME (Customer Requirements)
- 18,400 pieces per month
- 12,000 L/H per month
- 6,400 R/H per month
- Customer plant operates two shifts
- Palletized returnable tray packaging with 20 brackets in a tray and 10 trays on a pallet
- Customer orders in multiples of trays
- One daily truck shipment to the customer’s plant.
Work Time
- 20 days per month
- Two shift operation in all production departments
- 8 hours per shift, with overtime as required.
- Two 10 minute breaks during each shift
- Manual processes stop during breaks.
- Unpaid lunch
Waste
-The elements of production that add no value to the product
- Things to remember about waste:
- Waste is really a symptom, not a root cause
- Waste point to problems in the system
- To eliminate waste find & the address the root causes
Japanese define waste as:
- Muda (unproductive, non-value add)
- Mura (unevenness)
- Muri (overburden, unreasonable).
-If it is non-value adding, calling it Waste!
Overproduction
- Overproduction is the #1 cause of waste
- Making more than is required by the next process
- Making it earlier than is required by the next process.
- Making it faster than is required by the next process
Line Imbalance
-Individual Efficiency vs. System Efficiency
Takt time
- Synchronises pace of production to match pace of sales
* Takt Time = Available working time/ Customer demand
