OPMT 1720- Lean Six Sigma Tools for Process Improvement

Problem One (6 marks)

A key Lean Principle is Create Flow. Identify three tools that support or promote flow in a manufacturing company. Describe briefly how they help the flow of production.  

Problem Two (4 marks)

On a Value stream Map, we observe the Activity Ratio which is the ratio of Process Time to Lead Time. This number is typically very small because Process Time is much less than Lead Time.

What are two key drivers of excessive Lead Times?

What are two lean tools you could you use to do reduce lead time.

Problem Three (7 marks)

You are looking to improve the performance of one of your processes and decided to use OEE as a measure of productivity.

The process is stamping and has a cycle time of one second.

Your production crew starts at 7:00 am and finishes at 3:30 pm. During this shift, they are provided a 30 minute lunch break and two ten-minute coffee breaks.

The machine logs identified 7 stoppages during the shift. Two were bathroom breaks and five were due to changing to a new coil. When a coil is finished, it takes 15 minutes for a new coil to be loaded and made ready for production. The coil changes total 75 minutes and bathroom breaks total 11 minutes.

At the end of the shift, there were 18,640 pieces produced.  

Final Quality Control inspected the production run and ended up rejecting 913 pieces.

Calculate the Availability, Performance and Quality metrics for this and the OEE.