Exercise 1: Best demonstrated performance in production
Take all the key performance indicators in production and proceed as follows:
- Collect the statistical information on the key indicator sfrom the last two/three years.
- Go to the area and perform frequent observations (around 10 will do) for a short period of time in order to identify which is the optimum performance. The important aspect here is to quantify the most the production line or cell can produce when there are no obstacles.
- Compare all the observations and make a bar graph from them. The gap between the best demonstrated performance and all the other observations is the potential for improvement.
- Compare the best demonstrated performance with the statistical information collected. Make a bar graph. The gap shows the amount of lost opportunity during that period of time.
You can proceed in the same way to identify the downtime of your machinery. The full utilisation of your investment in equipment is also decisive to performance, so this exercise will identify room for improvement in this aspect.
- If available, collect the information on downtime, changeover time, etc of your equipment, line by line or unit by unit. Averages do not fit the purpose because they hide malfunctions and down time.
- Proceed in the same way as in Exercise 1, spending time at different stages of the process, registering the up and downtime, and in this case, classifying the reasons for down time (it could be a changeover, lack of staff to run it, poor quality, a breakdown, etc.)
- Make a bar graph with all the observations presenting the downtime as a percentage. The sample should be representative.
Exercise 3: Changeover Time Optimisation
If changeover time is relevant, you can investigate further by performing specific studies on how the changeovers are done.
- Get the information on when changeovers are scheduled.
- Observe several changeovers.
- During the changeover there some time that the line or machine has to be down, but it should be only the essential one. In every changeover there are a lot of activities that could be done before or after the machine is stopped. Make sure you identify and quantify the time of those activities. Preparation of tools and materials, calibration, etc,
- The time the machinery is down should be the minimum possible so the changeover should be planned with the required staff needed so they can work in parallel to minimise the time. Make sure you identify (maybe doing a mini-PERT or schedule) all the activities that can be done simultaneously in order to reduce changeover time.
- You can represent your conclusions in a visual way like the following chart
Best demonstrated performance should become your standards for production planning, so everytime you can’t achieve your best performance you are aware there’s an obstacle that is preventing you to achieve your maximum potential. And a corrective action should be taken. This is the only way to remove the obstacles so you achieve your maximum potential.
Regarding machine utilisation, breakdown time should be kept to a minimum. This is the responsibility of a maintenance/technical unit. Additional studies could be carried out in order to identify response time and preventive maintenance, two aspects that have a strong influence on downtime.
Finally, regarding changeover time, filming the changeovers and observing them in workshops is an effective way to make staff aware of the details that can optimise changeover time