Question

IN AN 8 HOUR SHIFT

Stage A 20 cars per hour               Initial set up time of 20 minute when changing the car model or size

Stage B 20 cars per hour               Must be shut down for maintenance and cleaning for 30 minute after every 90 minute of operation

Stage C 18 cars per hour               More customization, but no setups

Where would you place the buffers and what should the buffer capacity in terms of the number of cars?

Assume a cost of $5000/unit of storage capacity

If you add the buffers, how much does the system capacity increase? How many cars can you now produce per shift?               

                               

Reduce setup times        Setup times are always unproductive     

Stage A Reduce 20 minute setup               50% reduction, would cost $10,000

Stage B Reduce 30 minute downtime      50% reduction, would cost $20,000

                               

Would you reduce the setup time?         

If so, at which stages would you reduce setup time and how much would this add to the system capacity?             

Which is the better option? Why?            

What if we can do both?              

What is the increase to system capacity and at what cost?            

If you now consider all three options (the first two and the combined option), what is the best solution here?      

                               

Part B    Three models, model x, y and Z

                Setup is only required for changing the model type of Stage A     

                Consider an 8 hour shift per day and 6 day per week operation  

                Determine the batch sequence for the three models that will be processed through the week     

                               

                               

                               

                Parameters       

There's an equal number of batches produced for each model in the week. Therefore the entire weeks output would be equally split across the three models.              

Within a single day, you would need to produce at least one batch of each model.            

You could have more than one batch of each model produced within a single day              

                               

Develop a sequence for how the models will be produced over the 6 day period.

Multiple solutions are possible  

                               

Final complication           

What happens to Part B analysis if you have a fourth model, Model W in the mix?             

How would your solution change to incorporate this additional model?  

Answer 1