Lecture Introduction to operations management - Chapter 13: Scheduling operations

Lecture Introduction to operations management - Chapter 13: Scheduling operations. In this chapter we will discuss: Batch scheduling, gantt charting, finite capacity scheduling, theory of constraints, priority dispatching rules, planning and control systems.

Contemporary Concepts and Cases

Chapter ThirteenScheduling Operations

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Batch Processing Move-queue-work-wait-move

Work is done according to work orders

wait movequeue

move

move wait

queue move

move

move

– Release work orders to shop & issue 

dispatch lists for individual machinesMonitoring

– Maintain progress reports on each job 

until it is complete

Job Data for Scheduling Example

Job

Work center/

Machine Hours

Due Date

Where is the bottleneck?

Gantt Chart for Example

Conclusions about Batch Scheduling

Finite Capacity Scheduling (1)

Finite capacity scheduling loads jobs onto  work stations being careful not to exceed 

Finite Capacity Scheduling (2)

Theory of Constraints (TOC)

 A constraint is anything that is slowing down production—a bottleneck

– A machine or workstation

– The market

– Procurement system

The bottleneck determines the capacity of the system

Implication:  The operations manager should 

focus on the bottleneck to increase capacity 

and throughput (and make more money)

Theory of Constraints (TOC)

Ways of reducing the bottleneck or constraint:

Increase capacity

Divert work that doesn’t need to go through the bottleneck

Catch rejects before they get to the bottleneck

Increase output at the bottleneck

– Larger batches

– Reduced set­up times

Priority Dispatching Rules

End of Chapter Thirteen