Net production time (NPT)
Definizione del periodo di livellamento
| CW1 | CW2 | CW3 | CW4 | CW5 | CW6 | |
|---|---|---|---|---|---|---|
| 1 Week | 3280 | 3800 | 3520 | 3120 | 2760 | 3000 |
(CW1 + CW2)/2 = 3540
| 2 Week (avg) | 3540 | 3540 | 3320 | 3320 | 2280 | 2280 |
(CW1 + CW2 + CW3)/3 = 3533
| 3 Week (avg) | 3533 | 3533 | 3533 | 2960 | 2960 | 2960 |
(CW1 + CW2 + CW3 + CW4)/4 = 3430
| 4 Week (avg) | 3430 | 3430 | 3430 | 3430 |
Leveling period: 2 weeks
Media pezzi ogni 2 sett./giorno = (3540 + 3540) pz / 10 gg = 708 pz/g
Capacity for change over (C/O)
NO. of max C/O = 4,3
4 C/O per day
Calcolo dell’OEE considerando le perdite di cambio tipo
- Final assembly: 22,008 h – (4 C/O * 1 h) = 18,008 h/ 24 h = 75%
- Actuator production: 1215,36 min – (2 C/O * 60 min) = 1095,36 min/ 1440 min = 76%
- Amplifier production: 1100,16 min – (0 C/O * 60 min) = 1100,16 min/ 1440 min = 76,4%
- Body production: 1272,96 min – (3 C/O * 60 min) = 1092,96 min/ 1440 min = 75,9%
Step 6: Definition of EPEI
| Customer | Average daily customer demand | C/O | EPEI | NPK (pz/d) | (avg/d) |
|---|---|---|---|---|---|
| VW | (1120 + 1160)/10 = 228 | 1 | 1 | 40 | |
| Renault | (960 + 1440)/10 = 240 | 1 | 1 | 40 | |
| Daimler | (400 + 400)/10 = 80 | 0,5 | 2 | 40 | |
| BMW | (400 + 400)/10 = 80 | 0,5 | 2 | 40 | |
| Audi | (160 + 240)/10 = 40 | 0,5 | 2 | 40 | |
| Peugeot | (240 + 260)/10 = 40 | 0,5 | 2 | 40 |
TOT 708 4
Step 7: Average n° of cards/day
Step 8a: Leveling production plan
| Customer | Demand in cards/day | Day 1 | Day 2 | Day 3 | Day 4 |
|---|---|---|---|---|---|
| VW | (228/40) = 5,7 | 6 | 6 | 6 | 6 |
| Renault | (240/40) = 6 | 6 | 6 | 6 | 6 |
| Daimler | (80/40) = 2 | 4 | 0 | 4 | 0 |
| BMW | (80/40) = 2 | 0 | 4 | 0 | 4 |
| Audi | (40/40) = 1 | 2 | 0 | 2 | 0 |
| Peugeot | (40/40) = 1 | 0 | 2 | 0 | 2 |
TOT 18 18 18 18 18
Step 9: Calculation of required decoupling
(A) Define "RE"
Rt Loop = 3 days
RE = Rt Loop/(TT * NPK) = (Rt Loop * PR)/ (POT * NPK) = (3 * 240)/ (1 * 40) = 18 Kanban
(B) Define "LO"
LO = (Lot Size/NPK) – 1 = 0 (piano livellato)
(C) Define "WI"
WI = KANBAN TOT – RE – LO = 26 – 18 – 0 = 8
Replenishment time (RE) = 18
Process K spot 1 = 6
Tot. Kanban required for the lot size formation (LO) = 0
Supermarket K spot 2 = 6
Planned set up planned customer overflow K spot = 14
Withdrawal peaks (WI) = 8
Calculation of SA1 pacemaker
SA1 (supermarket)
(1) Calculate the biggest losses cumulated in the RT loop
- Day 8: 75% : 18K = 70% : x K x K = 16,8 losses = 1,2 cards
- Day 9: 75% : 18K = 71% : z K z K = 17,04 losses = 0,96 cards
- Day 10: 75% : 18K = 71% : w K w K = 17,04 losses = 0,96 cards