1. Crockery Case: Manufacturing Optimisation
Group 16:
F. Brandão
J. Karunakaran
P. Notenboom

2. Crockery Manufacturing – Dinner Service Sets Production Processes
Products differ in:
shape (5 models)
print (4 decorations)
20 different types

3. Function Requirements for the system
Delivery Performance Level – 95%
Lead Time – 1 week
Other goals:
Minimize stock and work-in-process
Demand:

4. Decoupling the Process
Define all different PUs
Create inventory points between PUs
Paste Making
Forming
Baking
Decoration
Hardening & Cooling
PU 1
PU 2
PU 3
Set Customer Order Decoupling Point
Tradeoff between:
Customer requested Lead Time
Supply Chain feasible throughput time

5. PU 1 (Paste making)
Requirement: Enough raw paste for 180 sets per week
Net production = 62 batches of 50 kg per week
Rejected = 0.2*62 = 13 batches each week
Usable paste = (62-13)*50 = 2450 kg
Possible sets = 2450/10 = 245 sets per week
Required production time = (180/245)*7 = 5.2 days per week
PU 1 can operate 7 days a week
For the required amount of paste, 5.2 days operation is sufficient

6. PU 2 (Forming + Baking processes)
Requirement: 180 sets per week
Scenario 1: COPD before PU 2
Available hours per week = 5*24 = 120 hours
Total Setup time = 5 models * 3 hours = 15 hours
Net Production time = 105 hours
Set production time = 0,5 hours
Sets max production = 105/0,5 = 210 sets
PU2 performance= 100% – 20% = 80%
Good sets max production = 80%*210 = 168 sets per week
Demand > Supply  95% delivery performance not possible
PU 2 (Forming + Baking processes)
Requirement: 180 sets per week
Scenario 2: COPD after PU 2
Available hours per week = 5*24 = 120 hours
Setup time = 3 hours
Set production time = 0,5 hours
PU2 performance= 100% – 20% = 80%
Required produced sets = 180/80% = 225 sets
Required production time = 225/(1/0,5) = 112,5 hours
Extra time available = 120 – 112,5 = 7,5 hours
Possible model changes = 7,5/3 = 2,5 changes per week
Requirement can be met with 5 changes every 2 weeks

7. PU 3 (Decorating, Hardening and Cooling)
Requirement: 180 sets a week, with every decoration type
Scenario 2: COPD after PU 2 and before PU 3
Time for model changes = 5*(1/6) = 5/6 hours per week
Time for decoration changes = 4*(2/6) = 8/6 hours per week
Decoration time = 0.4 hours per set
Available decoration time = (24*5)–(13/6) = hours per week
Total production = 117.8/0.4 = 294 sets per week
With the COPD before PU 3, demand lead time can easily be met

8. Goods Flow Control Function
Ensure sufficient capacity is available
Material coordination through constant lead times
Maintain the relationship between orders and sales
Be able to keep up with the demand and delivery performance level
Inventory before CODP:
Model 2: Σ Inv.Poisson(z>=0.95,Demand model k,Cummulative) for every k model -> 228 / 0.8 -> 285
Avg Inventory approximately (sets before CODP)= ( )/2=232,5