Cellular Scheduling for Batch Production

Abstract

Because multi-product schedules cause complexity in job assignments,
the tendency has been to employ additional manpower to cope
with the uneven workflow. The present work explores the problem of
scheduling batch production in a manufacturing system designed on
group ‘technology principles. Four manufacturing cells are designed,
and with the aid of a computer, components were processed in batches,
through machine cells. Comparison of performance (using the Economic
Batch Quantity (EBQ), Rota Cycling of Mixed Products (RCMP) and the
Period Batch Control (PBC) methods of batching) were obtained in order
to determine the best production policy when components are manufactured
for stock. An analysis of the performance of these batching
methods led to a better understanding of their relationship and of
the role of group technology in batch production management. Some insights
are offered with respect to the effect of these batching
variables on set-up times in cellular scheduling. Also, some other
observations are offered concerning implementation and operational
considerations.

Data used in the analysis in this study was obtained from a
medium sized engineering firm manufacturing various types and sizes of
lathe chucks. The company is described and its manufacturing problems
presented. Following a detailed analysis of the utilisation of
machines in the company's machine shop, a new manufacturing technique,
giving improved workflow, is proposed.

The final analysis shows that the Period Batch Control batching
method is not only superior to the other two methods in relation to
the cost of holding stock in the face of fluctuating market demand, but
also, in controlling the level of work-in-progress when this parameter
is used as a secondary criterion. It is also shown that cells designed
for single-line machine configuration are adaptable to multi-product
batch production schedules. Within each cell, the daily work
assignments of operators are balanced.

Date of Award	1977
Original language	English