8.1: Introduction

Last updated
Save as PDF

Page ID: 30992

\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\)

In this chapter, we consider another possible configuration of workstations called a job shop. A serial system processes one or at most a few types of parts that visit all of the system's workstations in sequence. Thus, serial systems are organized around required production operations. A job shop serves a wide variety of parts or jobs. Each type of job may use a different subset of the workstations and visit those stations in a unique sequence. Taken all together, the movement of jobs of all types between workstations appears to be random. Workstations are designed around common operations. For example, all of the milling machines may be gathered together at one workstation.

Several unique aspects of job shops must be taken into account. When a part using a machine is of a different type than its predecessor, the machine may require a setup task to change its operating parameter values or tooling. Different jobs may require significantly different amounts of processing time at a workstation. The routing of each type of job through the shop must be specified.