Category Archives: Reliability Centred Maintenance

PdM or CBM

The application of condition monitoring tools to look for signs of failure can result in cost increases if we are not careful.

Whilst we fully support CM, PdM and CBM this investment only creates a return when we can do something useful as a result of this new insight.

The failure modes that cause failures in our equipment must be managed and this can be via a mix of strategies, dependant upon the criticality of each functioning asset.

Simply buying in new CM technology will not improve the reliability of your asset population.

Our view, for what its worth, is that every company has a different aversion to risk, it has different missions and objectives. We have been taught this as a means to differentiate and to create a space for our organisations to flourish.

We must really understand what it is we can do to ensure that poor reliability does not impact in a negative way upon our business operation.

In the spirit that prevention is better than cure, intelligence gathered from our assets that we can use to inform how we maintain them is a good thing.

Whether we use this to derive either a predictive element or an early reactive capability, will be down to the strategy that each company develops.

RCM as a start point – no not really!

Planned Maintenance

Shakesby LinkedIn Post

This is an excellent article which makes very good reference to the potential benefits of RCM analysis on maritime assets. My only general concern, borne out of extensive discussions with ship management companies, is in regard to the investment/reward argument for deploying a full and formal RCM study in this sector. What I mean by this is that a blanket approach to RCM on a greenfield vessel is not considered to be a commercially attractive way to improve the operational reliability due to the cost to perform.

There are seven basic questions in RCM that must be answered – but who knows the answers? It is noted by Moubray that RCM cannot be performed by an individual nor indeed by members of a department but by a broad group of stakeholders, all of which bringing their own perspective, engineers from the ship, asset specific engineers, facilitation and process experts etc. These should all be in the room or at least be consulted in order to ensure that the RCM process is applied wisely as should the OEM.

We have been involved recently with reviewing RCM studies for UK vessels and have been left short by the fact that many of the system studies under review were completed by lone individuals, albeit with excellent skills and experience. This approach being borne out of commercial cost cutting. Whether the RCM output is good or not the scrutiny that would follow if tested, would likely conclude that RCM process had not been followed and as a result its output flawed.

This is why I do not recommend RCM as the starting point, far from it! When organisations recognise and decide to act upon a change management programme to deliver improved reliability, safety and performance and thus target the reduction of through life costs there becomes a need to shift the general strategy away from planned preventative tasks, as scheduled by a static system, to an optimising role where a greater proportion of time is devoted to finding better ways to do things. Thus, the first task is to establish the current state of the nation and to understand what the business goals are and what risks there are within the current approach to maintenance to being able to achieve these goals and to do so competitively.

The principles and general philosophy of RCM (RCM II Mowbray – for me) are excellent! Unfortunately, when embarking upon a business improvement initiative the change management and RCM facilitation costs far outweigh the clear measurable benefits – this is especially clear when we recognise the degree of redundancy we have built in due to the regulatory framework for ships.

That said, I do believe in RCM and actively promote it as a best practice approach, however,  I tend to embrace an optimising approach where you revisit the existing maintenance schedule and then take steps to understand where it is useful and where it is not. (Compare and contrasting the PMS and maintenance status for an organisation vs. its business needs) . One can then perform a criticality assessment based upon these needs and list all the systems in criticality order. From this you can chose the most appropriate strategy for each group of systems.

For example,  you may chose to group in low, medium and high categories for assets assessed under multiple criticality headings of safety, reliability, compliance and environmental consequence of failure.

You may then decide to run to failure all low criticality assets, perform CM and PM as necessary on medium criticality assets and perform OEM + CM on high critical assets – as a general headline strategy.

One can then extract the work order and frequency from the PMS and review either the total asset base or simply assets at each criticality level. The job, frequency and degree of invasion- grouping jobs as necessary and redefining criticality based upon ability to protect using CM, PM etc. – can then be re-uploaded and incorporated into the PMS.

This can be done in small packets according to resource and desire. In addition should it be deemed relevant a full RCM study could be conducted on high criticality assets to ensure that a function bespoke FMECA has been carried out and all single point and hidden failures considered and managed for these systems.

In short a multiple strategy approach. This appears to be more attractive as it allows companies to take bites according to their needs whilst retaining a robust process.