טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentLavi Yifat
SubjectA Reliability Approach to Spare Parts Supply
DepartmentDepartment of Quality Assurance and Reliability
Supervisor Professor Dov Ingman


Abstract

Companies who wish to support their product in the course of its use by the customer, operate a support system, such as a supply chain.


The total time it takes supply a spare part mostly serves as indicator of the process efficacy. Current approach, assumes this time to be uniformly distributed, and measures it only.


We present a new method for measuring the spare parts supply time, based on a Reliability-oriented approach, introducing a reliability model, using a set of existing reliability tools. With the supply process considered as a series-parallel system, it will be possible to identify its “failures” and “successes”, and evaluate the supply system reliability.


The paper comprises a characterization study of all sub-processes within the supply process, a development of an algorithm for determining the distribution of each sub-process population and development of criteria for it.



The conclusions of this study are on two main levels:

(a)    Efficacy of the reliability approach
1) The total supply time is not distributed uniformly and contains sub-processes with dissimilar populations.
2) Different distributions (mostly new and unfamiliar distributions) were found for the different sub-processes within the supply process.
3) The Spare Parts supply process is independent of the system type.

(b)         Effect of sub-process timing on the total supply time
Each sub-process has certain limitations in terms of its timing. With the supply process traversed backwards, criteria were developed for each sub-process, within the framework of the overall time criterion prescribed by the company.