|
Flow The Operation - 2 |
LEAN LOOK AT FLOW
When
we looked at line balancing in the previous examples we reviewed the line
balance as a histogram in terms of throughput in gross parts per hour of
each operation.
We did this because it is normally easier to initially understand
line balancing in terms of output.
On the shop floor we are often unaware of individual cycle times
but most of us know the line output in terms of parts per hour.
The first example was – |
| Op No | Operation Description | Actual Time Secs / Operation | Wait Time Secs / Operation | Total Time Secs / Operation | No of People used | Gross Parts / Hour |
|
05 |
Screw cap to shaft | 15 | 5 | 20 | 1 | 240 |
| 10 | Torque test & date stamp cap | 10 | 10 | 20 | 1 | 360 |
| 15 | Assemble 2 "O" rings to shaft | 20 | nil | 20 | 1 | 180 |
| 20 | Assemble 1st cover to shaft | 14 | 6 | 20 | 1 | 257 |
| 25 | Assemble 2nd cover to shaft | 14 | 6 | 20 | 1 | 257 |
| 30 | Inspect and pack assembly | 10 | 10 | 20 | 1 | 360 |
|
Totals |
83 | 37 | 120 | 6 | ||
|
Effectiveness % |
69% | 31% | 100% | |||
|
|
| If we were working on or close to an injection moulding machine we would normally be aware of the cycle times of each job as well as parts per hour. What we are going to do now is to look at the same chart for the flow line example but this time in terms of cycle time. |
|
|
| This is exactly the same chart but expressed in SECONDS / PIECE – this is the format we will use when looking at lean operations – if we decide to, that is!!! |