why-replace-all.txt

“At first sight replacing a complete system when only some parts of it are defective may seem strange. However, there are many real life examples, incl. from daily live.
So called complete clustering (Olde Keizer et al, 2017) may be optimal in case of a very strong economic dependence between the different parts of a system, e.g., due to a very high fixed set-up cost independent of the maintenance activities to be done as is the case of installations/facilities used in the generation and distribution of oil and gas. Note that often for safety reasons, the latter installations/facilities are monitored continuously. There also may be technical dependencies between parts of a system that may require combined replacement like in the case of replacing the cassette of a bike often also requiring to replace the chain, or the tires of an airplane which are required to have the same thickness. But also complete systems are replaced because replacing one or more of its parts may take much longer, which may result in big production losses. Another reason can be that there may be a high probability that when individual parts are replaced, other parts will be damaged/have to be damaged, requiring their replacement too.” PS APLLIES E.G. TO THE CASE STUDY ROBIN (VAN SPRANG) DID FOR MAREL.
 
Here also the reference to “a more complex system” that we discussed when you were here last Friday:
Marseguerra, M., Zio, E., Podo_llini, L., 2002. Condition-based maintenance optimization by means of genetic algorithms and
Monte Carlo simulation. Reliability Engineering and System Safety 77, 151{165. doi:10.1016/S0951-8320(02)00043-1.