Reduce Repair costs by 1/3rd A Case for Condition
Monitoring
CPM has investigated the reasons for failures for many years and as part of their quotation advised its customers on why the electric motor, pump, gearbox, fan assembly etc failed and offered recommendations on how to avoid reoccurrence of the failure.
Analysis of these failure trends tell us that more than 1/3rd of performing typical repairs is caused by secondary damage to the machine.
Typical Cost Breakdown
A typical cost breakdown of a centrifugal pump for example can be seen as follows:
Save 34% – How &
Why?
Once a component becomes worn or a shaft misaligned or an imbalance occurs then secondary damage is only a matter of time. If a bearing becomes worn for example it will soon cause its housing or seating to become worn also and the bearing will lose its fit. Or in the case of shafts becoming misaligned secondary damage will result to the bearings or seals, mountings and even the structural casing of the motor or fan, gearbox or pump.
When analysing thousands of failures over many years experience tells us that the cost of this secondary damage is 34% addition to the cost of the original repair. But not only this the time taken to effect the additional repairs could result in further downtime as the equipment failed without warning.
But in extreme cases a catastrophic failure could occur as in the case of an electric motor scoring the stator core as a result of a loss in bearing fit or a pump impellor scraping on the case of the pump. In these instances the equipment can be beyond repair and a replacement not always readily available.
This does not even take into account the loss of production caused by the resultant downtime which can, in instances, be many times the cost of replacing the asset.
A Case for Condition Monitoring
A common curve that illustrates the behaviour of equipment as it approaches failure is the P-F curve. The curve shows that as a failure starts manifesting, the equipment deteriorates to the point at which it can possibly be detected (P). If the failure is not detected and corrected, it continues until a failure occurs (F). The time range between P and F, commonly called the P-F interval, is the window of opportunity during which an inspection can possibly detect the imminent failure and address it. P-F intervals can be measured in any unit associated with the exposure to the stress (running time, cycles, miles, etc). For example, if the P-F Interval is 200 days and the item will fail at 1000 days, the approaching failure begins to be detectable at 800 days
Methods of Condition
Monitoring
As you can see from the above P-F Curve a number of methods can be used as part of a predictive maintenance programme. These methods of ‘Condition Monitoring’ , some of which have been available in a number of guises for some years, include Accelerometers, Thermal Imaging (Thermography), Ultrasound, Oil Analysis, Fixed point and portable Vibration Analysis. These systems are a fundamental element in a comprehensive predictive maintenance programme by providing an early warning in operating conditions and therefore allowing remedial action to be taken before any significant damage is done to the equipment.
Vibration Analysis
The latest equipment and instrumentation in Condition Monitoring is not only faster and non –invasive it is more accurate than whatever has gone before with higher and lower frequencies, and temperature ranges. It is also integrated with diagnostic software to not only help trouble shoot but also develops trends and therefore predicts life cycles and mean times to failure.
For more information on Condition Monitoring email info@cpm-uk.com or call +44 161 865 61