Analysis of critical machine reliability in manufacturing cells

Manocher Djassemi,Hamid Seifoddini

doi:10.3926/jiem.2757

Abstract

Purpose: In an increasingly competitive business environment, machine reliability problem merits special attention in operations of manufacturing cells. This is mainly due to flow line nature of the cellular layout, interdependency of downstream and upstream of machines related to each other. This study investigates the effect of critical machine reliability improvement on production capacity and throughput time in manufacturing cells. Design/methodology/approach: A discrete-event simulation model was developed to investigate the effectiveness of a reliability plan focusing on the most critical production machines in improving the performance level as an alternative to increasing the reliability of all machines. Four machine criticality policies are examined in the simulation experiments.Findings: The results of this experimental study indicated that an improvement of reliability of a limited number of machines leads to an increase in overall production capacity and speed in cellular manufacturing operations. A reliability plan, that focuses on a set of critical machines, potentially offers a more economical alternative to increasing the reliability of all machines in such facility.Research limitations/implications: The results demonstrate that to achieve higher production capacity and shorter throughput times, managers should consider directing more resources to increase the reliability of critical machines, particularly, those with shorter mean time to failure and higher utilization.Originality/value: The designed simulation model is unique in representing the dynamics of a real world manufacturing cell environment by encoding operational functions such as machine failure, maintenance resource allocation, material flow, job sequencing and scheduling. A new machine availability metric is defined as well.

Highlights

With the advent of global competition and advancements in technology, the reliability of production facility, and predictability in available resources have become critical in meeting the market demand
One such production facility is manufacturing cell known as cellular manufacturing system (CM) in which autonomous production cells, referred to as machine cells, are built using a group of dedicated dissimilar machines arranged in a series layout
In term of machine reliability, the results demonstrate an increased reliability of the critical machines from 10% to 30%, which improve the overall machine availability between 3 to 5% (Figure 4b)

Summary

Introduction

With the advent of global competition and advancements in technology, the reliability of production facility, and predictability in available resources have become critical in meeting the market demand. Simulation modeling is used to investigate how the manufacturing cell performs under certain criticality policies and machine reliability levels These policies identify a subset of machines with the: a) the shortest mean time between failures, b) longest queue length, c) highest utilization level, and d) longest mean repair time. The latter factor provide greater accuracy in performance data generated by the simulation model by starting a repair action whenever a maintenance technician is available as opposed to assuming a repair begins immediately after the failure of a machine occurs This subject has been discussed in a case study conducted by Mosley, Teyner and Uzsoy (1998) in which the effect of several maintenance staffing and scheduling policies investigated. The simulation is run for 100 days, 16 hours a day beyond transient period and replicated for 24 cycles, about 8 simulated years

Machine Criticality Heuristic

The Workforce

Mean Machine Availability

Findings

Discussion and Conclusions