Production managementReading time 11 min
Find the Seven Wastes in Everyday Work
Waste often looks like normal work: moving parts, waiting for information or making more than the next process needs. Use the seven categories to find the causes, not just label the symptoms.
01The seven wastes
| Waste | What it looks like in a shop | How to measure it |
|---|---|---|
| Transport | A semi-finished part crosses the plant three times to reach the next station | Travel distance, number of moves |
| Inventory | WIP stacked in the aisle, finished goods sitting two years | WIP value, age distribution |
| Motion | The operator walks to the far end for a gauge, every single time | Operator walking distance, retrieval time |
| Waiting | Waiting on drawings, material, inspection, a supervisor's signature | Waiting hours as a share of total |
| Overproduction | Fifty extra pieces made to round out a batch | Quantity released ÷ quantity ordered |
| Overprocessing | Polishing a non-functional face to Ra 0.8 | Compare against what the drawing asks for |
| Defects and rework | Reworking a dimension that went out of tolerance | Defect rate, rework hours |
02Mapping the work
Value stream mapping
Pick one representative product and follow it from order to shipment. Record the time spent processing and the time spent waiting at each step. The ratio of value-adding time to total lead time shows where work is delayed, but the map is most useful when the team investigates why those waits occur.
- In most shops that have not been through improvement work, that ratio lands between 0.5% and 5%.
- Which is to say: 99% of the time, the part is waiting.
- The room for improvement is almost entirely in the waiting, not in the cutting speed.
Spaghetti diagram
Trace a product or operator's movement on the floor plan. Repeated crossings and long detours can reveal a layout problem more clearly than a utilization report. Check the path with the people who work it every day.
Genchi genbutsu
Watch a complete work cycle at the workstation. Reports rarely show searching, reaching, waiting for approval or repeating a motion. Direct observation makes those losses visible before you choose an improvement tool.
03Tools for each loss
| Problem | Tool | Effect |
|---|---|---|
| Long changeovers force big batches | SMED | Setup time often drops by more than half |
| Hunting for tools takes forever | 5S | Motion and waiting waste |
| Too much WIP | Pull production / kanban | Inventory and lead time |
| Defects escape to the next station | Jidoka, mistake-proofing | Defects and rework |
| Layout drives transport | Cell production | Transport and waiting |
| The same problem keeps coming back | 5 Why, A3 | Root cause never addressed |
SMED separates changeover tasks into those that require a stopped machine and those that can happen while it runs. Move suitable work outside the stop period, then simplify what remains. Measure the new changeover rather than assuming a standard percentage saving.
04Mistakes to avoid
- Chasing machine utilization. Loading a non-bottleneck to the ceiling only manufactures WIP. See production scheduling.
- Doing 5S for the photographs. The place looks immaculate, the process never changed, and three months later it is back to how it was.
- Rolling it out everywhere at once. Pick one line as a model, get a result, then spread it, the success rate beats a plant-wide launch by a wide margin.
- Treating improvement as cost reduction. The goal is shorter lead time. Cost falling out of it is a result, not the method.