Easy and quick actions to reduce unplanned stops by applying simple preventive maintenance strategies.
Unplanned stops in production are an obvious area for improvement. They drive up downtime, increase the reaction time of the maintenance crews, and disturb the workflow of production and maintenance crews.
Pareto charts help to identify the production disturbances. This chart type is very helpful for focusing attention on repeating issues.
Our data shows that typically 70% to 80% of all production issues are repeaters.
Repeaters:
- have the biggest impact once eliminated
- are potentially systematic
- indicate that we have not learned from the past
- are annoying for the individual workers who keep experiencing them
Root cause analysis is a tool to understand the systematic cause behind a repeating issue.
In this article:
- Standard strategies for typical production issues
- Cleaning & lubrication (unplanned)
- Consumables & emptying
- Wear and tear of components
- Electrical components
- Calibration & alignment of measurement tools and equipment
Standard strategies for typical production issues
For some production issues, there are standard strategies that can be applied before a deeper root cause analysis can be performed.
Standard strategies help you act now, as a full root cause analysis can take time to complete.
These standard strategies often focus on avoiding unplanned stops by moving equipment maintenance work to planned maintenance windows. Some actions can be considered preventive maintenance.
Cleaning & lubrication (unplanned)
Cleaning and lubrication are part of equipment use. Those activities should not be needed during production.
How to identify
- Look in your logs for "sensor cleaning", "oil [component]", "grease [component]", etc.
- Check the log to see whether this happens repeatedly.
- Check that the cleaning is not triggered by an accident, crash or other stop reason, but happens on its own.
What to do
- Check whether the cleaning or lubrication is already on the maintenance schedule, and adjust the planned interval if it is.
- Schedule planned cleaning or lubrication during planned stop windows. This can be based on a time interval (every X weeks) or done during changeover.
The history chart in Maintmaster Manufacturing Intelligence (MI) helps you identify a suitable interval.
Scheduling planned cleaning is a preventive maintenance action. If the symptom is new, it is worth investigating why it started to be an issue, and why you need more regular cleaning. Possible reasons:
- Supplies changed
- New SKUs
- It is not done properly
Consumables & emptying
"Replace filter", "refill oil", "top up coolant", "drain reservoir", "drain sump".
Many machines require consumables by design. Running out of them during production is an avoidable problem.
Watch out not only for refilling, but also for overfilling collection tanks for consumables.
How to identify
- Search for the topics above: "replace", "refill", "empty", "drain", "overfilling".
- Is it by design? If not, there might be a component fault.
- Are the consumption levels in line with the manufacturer's specifications? If not, you might have a leak or another irregularity.
What to do
- Schedule the respective actions as part of regular maintenance.
- You can also do regular inspections if topping up is needed. For example, during changeover you check that the oil levels are OK and the collection tanks are below a threshold.
You can find the regularity by checking the history of the event with the history chart in MI.
Wear and tear of components
Mechanical or chemical wear after use is normal, and to a certain degree "by design". The manufacturer should provide guidance on which components wear down and what their expected lifetime is.
How to identify
- Regular replacements of components that are exposed to mechanical or chemical stress.
- The replacement of the part is repeating.
What to do
You have an indication that it is going to fail soon (visible wear, brittleness, reduced performance, higher energy use, noise):
- Schedule inspections and check for these early indicators.
- Schedule the replacement in a regular maintenance window.
No simple early indication is available:
- Consider keeping spare parts in stock. If the part breaks, you can switch quickly.
- Switch pre-emptively based on schedule or usage, if the cost of a stoppage is high enough to justify the replacement cost.
Electrical components
Typically, the failure of electrical components is hard to predict.
There are influences that allow for inspection and preventive actions:
- Signs of overheating or prolonged high temperature
- Signs of corrosion or leaks from parts
- Check the state of fuses
- Check that the power voltage is within specification
- Wear on cables and cords due to vibration or movement
- Check connections exposed to vibration or movement
- Check battery performance, such as holding charge
Calibration & alignment of measurement tools and equipment
Sensors and measurement tools often need regular calibration to ensure accurate readings. Calibration can happen as part of a line change, but can also be time-based.
Realignment may also be necessary for automation tools (robot arms, CNC axes, conveyor systems). For example, after a certain amount of use, a robot arm may need to be reset to its zero point.
Miscalibrated or misaligned equipment can lead to good products being rejected, production out of tolerance, and line stops due to automation problems.
In some industries, calibration is also important for staying compliant with certain quality standards.
How to identify
- The tool or equipment needs alignment to continue working, outside of the planned schedule.
- The action is not part of a regular line change, or of a line restart after an unrelated crash.
What to do
- Schedule calibration as part of regular maintenance.
- Inspect the alignment of equipment as part of regular maintenance.
- Consider training operators to do these tasks.
