Reliability Centered Maintenance
Reliability Centered Maintenance ( Reliability Centered Maintenance ), abbreviated RCM , is a risk-based strategy of maintenance of technical systems. The effect of possible errors on the function of the system is estimated and the necessary maintenance measures are defined to ensure functionality.
methodology
In risk-based maintenance there are several basically equal strategies : In the failure-oriented strategy , the system is operated until spontaneous failure. The main focus is on quick repairs after a failure. With preventive maintenance , the failure should be avoided or delayed: Either through interval-based or periodic maintenance, in which, for example, the expiry of deadlines or certain counter readings are the trigger for maintenance, or through predictive maintenance, in which components are preventively exchanged with regard to future failure become. With condition-based maintenance , the required maintenance measures are derived from the condition of the system determined by inspection, continuous monitoring or simulation.
Reliability-oriented maintenance (RCM) helps determine the optimal maintenance strategy for operating the systems.
John Moubray described RCM as "a process of determining what needs to be done to ensure that a (technical) system continues to function in an operating environment".
In an RCM analysis, the system to be examined is first delineated. Then a predefined decision tree with 7 questions is run through for this:
- What are the functions and required performance data of a system in the operating environment?
- In what form can the functions be disturbed or is the performance not achieved?
- What are the causes of the respective malfunction?
- What if a malfunction occurs?
- How does the dysfunction affect?
- What can be done to predict or avoid a dysfunction?
- What should be done if a suitable activity to predict or avoid is found?
The corresponding results are documented.
The RCM decision tree already has a key focus on the effects of a malfunction in relation to:
- safety
- environment
- Follow-up costs
The use of RCM makes sense in the life cycle of a system in terms of engineering and operation.
Together with the documentation, the standardized procedure allows a simple review of an RCM analysis and an easy adjustment of the original planning to the practical experience.
In addition, various target values can be defined for reliability-oriented maintenance. While it can be opportune in one company to define cost savings as a goal, in other companies or industries the system availability is the goal and the costs are of secondary importance. Plant safety, minimal spare parts requirements and depreciation-optimized strategies can also be the goal of maintenance.
Ultimately, it boils down to distributing the existing maintenance budget to the existing equipment in a targeted manner.
In expanding the concept of reliability, one can then move on to risk-based maintenance. If two identical pieces of equipment have an identical state with regard to all the recorded variables, further criteria must be included in the decision as to which piece of equipment is to be repaired "first".
These “soft” or rather “non-technical” variables can be composed of completely different areas. For example, the possible costs of a failure of the equipment can be included in the evaluation, so that equipment whose failure causes considerable financial damage is given a higher priority than another, otherwise the same equipment with the same status vector.
origin
RCM was first mentioned in 1978 in a publication sponsored by the Department of Defense. This work documented a process in commercial aviation that had been in development for over twenty years. The process showed a very high level of fulfillment of safety and reliability goals. The primary beneficiaries of this publication are and have been the agencies that supported the work, the US National Aviation Administration, the aircraft industry, individual airlines such as United Airlines, their employees and suppliers, and especially Boeing, as well as airline passengers and the general public.
Aladon network
The term RCM is protected and is now owned by the Aladon Network . There is a certification for RCM experts to ensure the standard of RCM analyzes.
The protection of the name RCM has meant that modifications may not be used under the name RCM.
Individual evidence
- ^ Moubray, John: RCM II, Reliability-centered Maintenance: Elsevier, Butterworth-Heinemann, 1997.
- ^ Moubray, John: RCM II, Reliability-centered Maintenance: Elsevier, Butterworth-Heinemann, 1997.
- ↑ The Aladon Network .