Bad actors from a reliability point of view
Several benchmark studies have shown that assigning a large number of errors to a relatively small proportion of the installed devices. Often the Pareto Principle or the 80/20 rule applies: 80% of the problems are caused by 20% of the devices. Every reliability, asset or maintenance manager knows the problem cases or bad actors do. They are frequent in the workshop for repair and some even spend there as much time as their function instead. Their impact on the MTBF (Mean Time Between Failure) of such order to chasten the best way to improve the MTBF and the OEE (Overall Equipment Efficiency) of the installation.
Failure Cycle Each machine part has a certain failure cycle, which we maintenance-reliability circles often express on the basis of the PFcurve: performance in function of time. The bad actor answers often not there. The lifetime is limited by a sudden failure shortly after or during commissioning or after x time
APPROACH The focus of Allied Reliability Group is therefore Fri point P in tackling the bad actor: v. r the start of the failure. In addition, the company focuses on the cause of failure, with the intended result lengthening the time between installation and failure, as well as shifting the time period between the points P and F. The approach to bad actors requires a structured process, for these reasons: causes and solutions are seldom obvious; the process forced the causes and solutions based on facts; The process also ensures that solutions are linked to causes. Methodology The following methodology is based on experiences and best practices similar to the DMAICproces (Define Measure Analyze Improve Control). Definition (s) or identification of a bad actor, we limit this article to pumps. Which fall under the heading bad actor? A good definition is of primary importance, and can be different for each company or unit. For one, it is the sudden, unexpected failure which partly explains lamb production. For others again the chronic poor performer. MTBF numbers are a good start, but obviously do not accurately restores image. Yet should the 25% lowest scorers in the MTBF table to be given a weight depending on the number of hours and the oeilijkheidsgraad; Each pump with one or more interventions per year; Repair costs more than 10,000 euros per year An annual repair cost that is excessively higher than the average in its category; The Plant Performance Killers pumps Infant Mortality- set these values ??should then be compared to the criticality: how crucial they are in the production process; what are the costs and complexity of the solution?
Collect data, facts and information after the MTBF list is filtered, all relevant device data must be collected Will to convert it to information. This is a very labor-intensive work, in view of the data often is not centrally stored. She can indeed scattered in CMMS, SAP registers, Excel sheets, recovery records, emails etc. One of the hardest pillars is the loss of production, unless the company uses APM (Asset Performance Management). Start with the Technical Journal drawn up by Engineering or Maintenance, the Pump Data Sheet from the supplier, the purchase order, the pump curve and other available information, such as performance testing, calculations, etc.