WHITE PAPER
+44 (0)1788 555000
|
|
+44 (0)1788 555000
|
|
Maintenance Myths, Mindsets & Mistakes
|
There are four basic types of maintenance that can be applied to equipment. The task intervals for the different types of maintenance are dependent on different factors – these factors are often poorly understood. This lack of understanding is a common cause of poor operational reliability and availability.
A common statement that maintainers make is “We need to check our critical equipment more often than our non-critical equipment”. This sounds like good ‘common sense’ but is, in fact, wrong for On-condition maintenance. A common statement that maintainers make is “It doesn’t fail so often, therefore, I don’t need to check it so often”. This sounds like good ‘common sense’ but is wrong for On-condition maintenance. Another common statement is “We monitor our equipment MTBFs carefully so that we can determine how often we should overhaul/replace equipment”. In fact the task interval (ie the fixed interval at which the scheduled restoration or discard task is carried out) is determined by the “life” of the equipment. Crucially, “life” and MTBF are different. |
Many maintainers think that there are just three types of maintenance: predictive, preventive and corrective – ie they mistakenly think that On-condition tasks (ie predictive maintenance) and Failure-finding tasks (ie detective maintenance) are one and the same; they are completely different
The belief that collecting failure rate data leads to better maintenance is, in most instances, a myth. The data we need is rarely available and so key decisions about maintenance have to be made in the absence of hard data. Organisations that rely heavily on protective systems frequently reduce the maintenance carried out on them in order to reduce overall spend; they assume that the protective systems will operate when required. These systems can and do fail; organisations may be vulnerable to serious consequences if the protected function subsequently fails. Maintenance spend must be directed to where it will do the most good. |
RCM Task Type |
Description |
Common Synonyms |
On-condition |
Check to see if equipment is failing |
‘Predictive Maintenance’, ‘Condition-based Maintenance’ or ‘Condition Monitoring’ |
Scheduled Restoration & Scheduled Discard |
Overhaul or replace equipment before it fails |
‘Preventive Maintenance’ or ‘Scheduled Overhauls/Replacements’ |
Failure-finding |
Check to see if equipment has failed |
‘Functional Checks’ or ‘Detective Maintenance’ |
Corrective |
Corrective action following discovery of failure or potential failure |
‘No scheduled Maintenance’ or ‘Run-to-failure’. Also includes work carried out following other types of maintenance |