Avoid robotics downtime through maintenance

ATM Automation explains why preventative maintenance is the single most important thing you can do to avoid problems with your robot system or automation.

Facing sustained pressure to improve output and reduce costs, many manufacturers are turning to preventative maintenance as a way of improving the performance of their automation and robotic systems.

Unexpected breakdowns and the subsequent downtime associated with a robot or system failure can drastically effect productivity and, therefore, profitability.

But the danger of such an event occurring can be mitigated through preventative maintenance.

By adhering to a well-structured maintenance plan you can identify potential problems before they become serious, improve productivity, and save money, as well as extending the useful life of the equipment and improving the mean time between failures (MTBF).

Despite the obvious benefits of preventative maintenance, some companies still ignore the subject as it is perceived as taking time and costing money.

With most maintenance procedures being performed with the robot or system shut down, these breaks in the production schedule are mooted as being disruptive.

However, in reality the unplanned stoppages that will occur due to lack of maintenance are almost always longer, and therefore more costly, than the delays caused by a properly organised maintenance plan.

Preventive maintenance should follow a clearly defined schedule that is tailored to suit the equipment within the cell and the application to which it is being applied.

For example, robot or automation cells performing simple pick and place operations will have much more basic schedules than a complex system incorporating several different technologies or processes, which may require inspection at several points in a single shift.

With such a wide variety of robots available - from basic 'sprue picker' units to three-axis Cartesian robots to highly sophisticated six and seven-axis robots - the scheduled maintenance programme for a particular unit should always include the recommendations from the robot's manufacturer.

These are usually based around specific time intervals or production use.

The most basic preventative maintenance tasks are carried out daily or at the start of each shift.

Simple checks on the condition of cables and harnesses, checks on lubrication levels, the integrity of cell guarding and a general review of the working area, although basic, can often highlight items that could result in serious failure or safety issues if left unattended.

Where robots are operating within more complex automation cells, other checks should be added to the daily schedule.

These will be specific to the other components of the system, such as conveyors or parts feeders, and all checks should reflect the original manufacturer's recommendations.

As well as the basic daily or shift checks, a comprehensive schedule will include weekly, monthly, quarterly and yearly checks for all elements of the automation cell.

While most checks can easily handled by in house maintenance teams, it is best for the quarterly and yearly checks to be undertaken by a field service team from the manufacturer or a specialist.

Quarterly and yearly maintenance schedules are more comprehensive than their more regular counterparts and can include tasks requiring specialist tools, equipment or knowledge.

Servicing at this level, by an experienced engineer, will ensure the robot and any associated equipment remains operational and at its most efficient.

At the end of such a maintenance and service visit, the engineer compiles a report for the customer confirming the maintenance procedures that have been carried out.

They will also recommend remedial actions for any item needing attention or replacement to avoid failure in the future.

While a comprehensive maintenance programme will improve the MTBF, another important factor contributing to productivity is the mean time to repair (MTTR).

Although the potential for unexpected breakdowns is greatly reduced by thorough maintenance, when the inevitable does happen it is essential to get the system back into action as quickly as possible.

The customer can have a significant and immediate influence on the MTTR by ensuring properly trained personnel and spare parts are available on-site.

Operators and maintenance teams can be trained on courses tailored to suit specific robots and systems.

Depending upon the system's complexity, essential spares may include basic items such as fuses, relays, cables and lamps or more comprehensive items such as motors, drives, control boards and bearings.

When combined, pre-planning service schedules to cause minimal disruption to production and employing well-trained operators and maintenance personnel will ensure high uptimes, optimal productivity and more profit for manufacturers.

Back to top