Authors: S.P. Sharma, Harish Garg
Addresses: Department of Mathematics, Indian Institute of Technology Roorkee (IITR), Roorkee 247667, Uttarakhand, India. ' Department of Mathematics, Indian Institute of Technology Roorkee (IITR), Roorkee 247667, Uttarakhand, India
Abstract: Reliability, availability and maintainability (RAM) analysis of a system is helpful in carrying out design modifications, if any, and it is required to achieve minimum failures or to increase mean time between failures (MTBF), and thus it is used to plan maintainability requirements, optimise reliability and maximum equipment availability. To this effect, this paper presents the application of RAM analysis in the process industry. Fuzzy Lambda–Tau methodology is used here to model the system behaviour. Each system components, failure rate and repair time are represented by triangular fuzzy numbers with known spread. The methodology uses Petri nets to model the system instead of fault tree because it allows efficient simultaneous generation of minimal cuts and path sets. Various reliability parameters such as MTBF, expected number of failures (ENOF), reliability, availability, etc. are calculated. The computed results are presented to plant personnel for their performance considerably by adopting and practicing suitable maintenance policies/strategies.
Keywords: reliability; availability; maintainability; PNs; Petri nets; Lambda–Tau methodology; fuzzy sets; fuzzy logic; urea decomposition; fertiliser plants; modelling; system components; failure rate; repair time; maintenance policy.
International Journal of Industrial and Systems Engineering, 2011 Vol.8 No.3, pp.271 - 297
Available online: 25 Jul 2011 *Full-text access for editors Access for subscribers Purchase this article Comment on this article