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

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

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

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

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

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

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) = 117.8 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

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)= (285 + 180)/2=232,5