AIMS

This assignment aims to give you a chance to practice the skills you have learned in this unit to analyse a real production system. The specific goals of this assignment are listed:

1 Be able to use Value Stream Mapping (VSM) to analyse production system

2 Be able to identify the bottleneck, calculate the utilisation of different manufacturing resources under the maximum TH conditions

3 Build a simulation model to simulate a real production process with variability

4 Be able to analyse the simulated data and compare it with the theoretical calculation learned in the class

5 Identify the waste and 3Ms and come up with potential solutions

BACKGROUND

Fastcar is a foundry that is focusing on making an engine block for the automobile industry. Its customer is a car engine factory that assembly the engine block with other components into an engine.

Figure 1 Engine Block of a car

In Fastcar, the Engine block is made by the die casting process withAl alloy.Figure 2 shows the manufacturing process of die casting. The melting Al liquid will be poured into the casting machine and pumped into the die. In Engine block manufacturing, the die is made of metal which can be reused, while the core is made of sand. The sand core can only be used for a single-engine block.

Figure 2 Die casting process

The video in this link showshow to use die casting to make an engine block.

https://youtu.be/N2hYTdrzujI

Fastcar received an order from its customer every two weeks. The order is sent to the marketing office of the Faster car via its online ordering system. The marketing office will upload this information on its  internal ERP system. Then,  the production planning office can be noticed and contacts the purchasing department to order raw materials (Al  alloy) and also prepare the consumables. The production planning office will also inform the workshop management team of the production plan. Workshop management will coordinate each workstation to make enough engine blocks to meet the customer orders. The engine block will be fabricated and then stored in the FG inventory. After all the units  have  been  fabricated  in the  current order. Then  Fastcar will  ship the engine  block  to  its customer by truck. Fastcar is working five days per week and 8 hours per day.

In the workshop of Fastcar, the following process/resource should be used.

•    Step 1: Makesand core

•    Step 2: Die casting

•    Step 3: Clean and Inspection

•    Step 4: Machining

The detailed time and specifications for each resource are provided in a data file.

TASKS

Task 1 (5 marks): Based on the given data collected from the production line calculate the maximum TH (Also known as process capacity). During the calculation, do not consider the machine failures and use the mean process time for calculation. Also, assume the batch size in the core making step is one. And then calculate the WIP (not include materials in the raw material inventory and FGs inventory), resource capacity, utilisation and flow time of this production line under maximum TH (no buffer inventory before each manufacturing resource is needed, also do not consider the time spend in raw material inventory and FGs inventory). Calculate resource capacity and utilisation for each step.

Task 2 (5 marks): Build a simulation model to simulate the real production scenario. In this simulation model, we do not consider the variability in the process and the number of units that arrive in each order.  But you  should find the  optimal  batch  size to maximize the production TH while keeping inventory as low as possible.  For each resource, we use  mean process time and  do  not consider machine breakdown. Based on the simulation model you should calculate: