The RCM process: Seven steps to implement reliability centered maintenance
There are several different methods for implementing reliability centered maintenance that are summarized in the following seven steps.
Step 1: Selection of equipment for RCM analysis
The first step is to select the piece of equipment for reliability centered maintenance analysis. The equipment selected should be critical in terms of its effect on operations, its previous costs of repair, and previous costs of preventive maintenance.
Find the best equipment for RCM with this criticality analysis template
Step 2: Define the boundaries and function of the systems that contain the selected equipment
The equipment belongs to a system that performs a crucial function. The system can be large or small, but the function of the system, and its inputs and outputs, should be known. For example, the function of a conveyor belt system is to transport goods. Its inputs are the goods and mechanical energy powering the belt, while its outputs are the goods at the other end. In this case, the electric motor supplying the mechanical energy would be considered as part of a different system.
Step 3: Define the ways in which the system can fail (failure modes)
In step 3 the objective is to list all of the ways that the function of the system can fail. For example, the conveyor belt may fail by being unable to transport the goods from one end to the other, or perhaps it does not transport the goods quickly enough.
Step 4: Identify the root causes of the failure modes
With the help of operators, experienced technicians, RCM experts, and equipment experts, the root causes of each of the failure modes can be identified. Root causes for failure of the conveyor could include a lack of lubrication on the rollers, a failure of a bearing, or a loosened belt.
Use this template and stop spending hours doing a root cause analysis
Step 5: Assess the effects of failure
In this step, the effects of each failure mode are considered. Equipment failure may affect safety, operations, and other equipment. The criticality of each of these failure modes can also be considered.
There are various recommended techniques that are used to give this step a systematic approach. These include:
- Failure modes and effects analysis (FMEA)
- Failure, mode, effect and criticality analysis
- Hazard and operability studies (HAZOPS)
- Fault tree analysis (FTA)
- Risk-based inspection (RBI)
The most important failure modes will be determined at the conclusion of this systematic analysis. Ask yourself questions such as “Does this failure mode have safety implications?”, and “Does this failure mode result in a full or partial outage of operations?”. Your answer is the most important failure modes that should be prioritized for further analysis. Importantly, the failure modes that are retained include only those that have a real probability of occurring under realistic operating conditions.
Step 6: Select a maintenance tactic for each failure mode
At this step, the most appropriate maintenance tactic for each failure mode is determined. The maintenance tactic that is selected must be technically and economically feasible.
Condition-based maintenance is selected when it is technically and economically feasible to detect the onset of the failure mode.
Time or usage-based preventive maintenance is selected when it is technically and economically feasible to reduce the risk of failure using this method.
For failure modes that do not have satisfactory condition-based maintenance or preventive maintenance options, then a redesign of the system to eliminate or modify the failure mode should be considered.
Failure modes that were not identified as being critical in Step 6 may, at this stage, be identified as good candidates for a run-to-failure maintenance schedule.
Step 7: Implement and then regularly review the maintenance tactic selected
Importantly, the RCM methodology will only be useful if its maintenance recommendations are put into practice. When that has been done, it’s important that the recommendations are constantly reviewed and renewed as additional information is found.
The bottom line: the impact of reliability centered maintenance
Since the end product of a well-executed RCM analysis is that an appropriate maintenance strategy will be selected for each piece of equipment, the impact is an overall improvement of reliability. RCM aims to reduce costs, improve safety, and eliminate maintenance tasks that are not effective or appropriate for a given piece of machinery. Implementing RCM processes allows you to avoid a one-size-fits-all mindset that could waste valuable time and resources.
