Bottlenecks in Production Lines with Rework: A Systems Approach
نویسندگان
چکیده
The bottleneck (BN) of a production system is a machine with the strongest effect on the system’s throughput. In this paper, a method for BN identification in serial lines with rework and Bernoulli machines is developed. In addition, the paper provides two system-theoretic results: First, it demonstrates that BNs may be shifting not only because of changes in machine and buffer parameters but also due to changes in quality of parts produced. Second, it shows that if the split and the merge machines are not the last and the first, respectively, Bernoulli lines with rework do not observe the property of reversibility, and downstream machines may have a larger effect on the throughput than those upstream.
منابع مشابه
Scheduling Accumulated Rework in a Normal Cycle: Optimal Batch Production with Minimum Rework Cycles
In this paper we consider a single machine system that produces items part of which are defective. The defective items produced in a time period, consisting of several equal cycles, are accumulated and are all reworked in the last cycle of this period called the rework cycle. At the end of the rework cycle the whole process will start all over again. The first significant objective of this stud...
متن کاملAbsorbing Markov Chain Models to Determine Optimum Process Target Levels in Production Systems with Rework and Scrapping
In this paper, absorbing Markov chain models are developed to determine the optimum process mean levels for both a single-stage and a serial two-stage production system in which items are inspected for conformity with their specification limits. When the value of the quality characteristic of an item falls below a lower limit, the item is scrapped. If it falls above an upper limit, the item is ...
متن کاملOptimal Batch Production for a Single Machine System with Accumulated Defectives and Random Rate of Rework
In this paper we consider an imperfect production system which produces good and defective items and assume that defective items can be reworked. Due to the nature of rework process we do not restrict the rework rate to be equal to normal production rate or constant and assume that it is a random variable with an arbitrary distribution function. We also assume as it is true in most real world s...
متن کاملPerformance Analysis of Production Systems with Rework Loops
This paper is devoted to the study of production systems with rework loops. Such systems are often encountered in manufacturing plants and accurate performance analysis is needed for design and continuous improvement. However, no analytical methods to evaluate its production rate are available in the current literature. In this paper, we present an aggregation procedure using overlapping decomp...
متن کاملEconomic Production Quantity in Reworkable Production Systems with Inspection Errors, Scraps and Backlogging
The classical economic production quantity (EPQ) model is a well-known and commonly used inventory control technique. Common assumptions in this model are that all units produced are of perfect quality and shortage is not allowed, since in practice shortage, non-conforming product or scrap items are possible, these assumptions will underestimate the actual required quantity. The objective of th...
متن کامل