Why do we need to reduce Process Downtime?
We need to reduce process downtime because in most organizations it is one of the main issues responsible for increasing lead times. If you can reduce the process downtime, you will reduce lead time, and this will allow you to deliver products or services to your customers in less time.
How do we reduce Process Downtime?
An organization will need to collect data to track and trend how effective their equipment is at meeting customer demand. The collected data will be used to calculate OEE (Overall Equipment Effectiveness). OEE is focused on three key metrics, Availability, Performance and Quality. These three key metrics are used to identify and eliminate the six big losses:
Six Big Losses – An Example
An typical example used for planned downtime is equipment changeovers. Long changeover times create several problems, the main one is that it forces a company to participate in batch production. One of the goals of lean manufacturing is to reduce or eliminate batch production, and implement continuous flow. One of the lean manufacturing tools used to reduce equipment changeover times is Quick Changeovers.
What is Quick Changeover?
A Quick Changeover is a improvement process using the SMED concept for reducing equipment downtime. The definition of a changeover is the time between the last good part of the current run until the first good part off the next run. The time taken to set up a process is non-productive and therefore, non value added from a customers perspective. It takes longer to manufacture components because orders have to wait until the equipment can produce a good part before an order can be started and the work completed. Lead time increases because of long changeover times.
What are the steps in a Quick Changeover?
There are four steps to implementing SMED:
- Document and record a changeover to identify the activities.
- Separate activities into internal and external elements.
- Convert internal into external elements.
- Streamline all aspects of the changeover process
What affect will implementing SMED have on production?
Long changeover times force a business to manufacture large batches to compensate for the downtime and loss of production. Implementing quick changeovers using SMED will reduce the amount of time to set up a machine. This will reduce the lead time, and increase the number of available production hours.